BIODIESEL FUEL COMPOSITIONS HAVING INCREASED OXIDATIVE STABILITY

COMPOSITIONS COMBUSTIBLES DE BIODIESEL PRESENTANT UNE MEILLEURE TENUE A L'OXYDATION

English Abstract

The present invention relates to biodiesel fuel compositions that have
improved oxidation stability. More specifically, the biodiesel fuel
compositions include at least one antioxidant that increases the oxidative
stability of the fuel. The biodiesel fuel compositions may also include an
antioxidant mixture, or an antioxidant mixture in combination with a polar
and/or nonpolar solvent, that increases the oxidative stability of the fuel.

French Abstract

La présente invention concerne des compositions combustibles de biodiesel dotées d'une meilleure tenue à l'oxydation. Plus particulièrement, les compositions combustibles de biodiesel contiennent au moins un antioxydant qui améliore la tenue du combustible à l'oxydation. Les compositions combustibles de biodiesel peuvent également contenir un mélange d'antioxydants ou un mélange d'un antioxydant combiné avec un solvant polaire et/ou non polaire, qui améliore la tenue du combustible à l'oxydation.

Claims

CLAIMS

What is Claimed is:

1. A fuel composition, the composition comprising:
a. a biodiesel from a source other than rapeseed oil, frying oil, sunflower
oil, and beef tallow; and
b. at least one antioxidant selected from the group consisting of 3,4,5-
trihydroxybenzoic acid n-propyl ester, 1,2,3-trihydroxybenzene,
butylated hydroxyanisole, 2,6-Di-tert-Butyl-l-Hydroxy-4-
Methylbenzene, alpha-tocopherol acetate, alpha-tocopherol, gamma-
tocopherol, delta-tocopherol, dilauryl thiodipropinate, isopropyl 2-
hydroxy-4-methylthio butanoate, propyl gallate, dodecyl gallate, gallic
acid, octyl gallate, ascorbyl palmitate, lecithin, stearyl citrate, palmityl
citrate, chlorophyl, pyrogallol, alpha naphthol, ascorbic acid, natural
tocopherol, citric acid, sage extract, rosemary, eugenol, natural
antioxidant, and 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline.

2. The fuel composition of claim 1, wherein the biodiesel is produced from
soybean oil, the antioxidant is 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline,

and the fuel contains from about 50 ppm to about 500 ppm 6-ethoxy-1,2-
dihydro-2,2,4-trimethylquinoline.

3. The fuel composition of claim 1, further comprising an additive selected
from
the group comprising of cetane improvers, ignition accelerators, metal
deactivators, corrosion inhibitors, thermal stabilizers, detergents, antiwear
agents, and demulsifiers.




4. A fuel composition, the composition comprising:
a. a biodiesel; and
b. an antioxidant mixture, the mixture comprising at least two antioxidant
selected from the group consisting of 2-tert-butylhydroquinone, 3,4,5-
trihydroxybenzoic acid n-propyl ester, 1,2,3-trihydroxybenzene,
butylated hydroxyanisole, 2,6-Di-tert-Butyl-1-Hydroxy-4-
Methylbenzene, alpha-tocopherol acetate, alpha-tocopherol, gamma-
tocopherol, delta-tocopherol, dilauryl thiodipropinate, isopropyl 2-
hydroxy-4-methylthio butanoate, propyl gallate, dodecyl gallate, gallic
acid, octyl gallate, ascorbyl palmitate, lecithin, stearyl citrate, palmityl
citrate, chlorophyl, pyrogallol, alpha naphthol, ascorbic acid, natural
tocopherol, citric acid, sage extract, rosemary, eugenol, natural
antioxidant, and 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline.

5. The fuel composition of claim 4, wherein the biodiesel is produced from a
source selected from the group consisting of soybean oil, yellow grease, corn
oil, rapeseed oil, coconut oil, peanut oil, palm oil, fish oil, marine oil,
cottonseed oil, mustard seed oil, camelina oil, jojoba oil, hemp oil, tallow,
poultry fat, lard, safflower oil, jatropha oil, algae oil, and sunflower oil.

6. The fuel composition of claim 4, wherein the biodiesel is produced from
rapeseed oil.

7. The fuel composition of claim 4, wherein the biodiesel is produced from
algae
oil.

8. The fuel composition of claim 4, wherein the biodiesel is produced from
soybean oil.

9. The fuel composition of claim 8, wherein the antioxidant mixture comprises
6-
ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-tert-butylhydroquinone.

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10. The fuel composition of claim 8, wherein the antioxidant mixture comprises

butylated hydroxyanisole, 2,6-Di-tert-Butyl-1-Hydroxy-4-Methylbenzene, 6-
ethoxy-6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-tert-
butylhydroquinone.

11. The fuel composition of claim 10, wherein the antioxidant mixture
comprises
from about 20 ppm to about 500 ppm of a mixture of Butylated
Hydroxyanisole and 2,6-Di-tert-Butyl-1-Hydroxy-4-Methylbenzene, from about
20 ppm to about 500 ppm of 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline,
and from about 10 to about 60 ppm of 2-tert-butylhydroquinone.


12. The fuel composition of claim 8, further comprising a nonpolar solvent.


13. The fuel composition of claim 12, wherein the antioxidant mixture
comprises
butylated hydroxyanisole, and 2,6-Di-tert-Butyl-1-Hydroxy-4-Methylbenzene
and the nonpolar solvent is a vegetable oil.


14. The fuel composition of claim 4, further comprising a polar solvent.

15. The fuel composition of claim 4, the composition further comprising a
petroleum based diesel fuel.


16. The fuel composition of claim 15, the composition comprising from about
20%
to about 30% by weight of the fuel composition of claim 4 and from about 70%
to about 80% by weight petroleum based diesel fuel.


17. The fuel composition of claim 4, further comprising an additive selected
from
the group comprising of cetane improvers, ignition accelerators, metal
deactivators, corrosion inhibitors, thermal stabilizers, detergents, antiwear
agents, and demulsifiers.



62




18. A fuel composition, the composition comprising:
a. a biodiesel;
b. a first antioxidant having Formula (I);

Image

wherein:
R1, R2 , R3 and R4 are independently selected from the
group consisting of hydrogen and an alkyl group having
from 1 to about 6 carbons; and
R5 is an alkoxy group having from I to about 12 carbons;
c. a second antioxidant not having Formula (I);
d. a polar solvent; and,
e. a nonpolar solvent, wherein the two solvents form a homogeneous
liquid.


19. The fuel composition of claim 18, wherein the second antioxidant is
selected
from the group consisting of 2-tert-butylhydroquinone, 3,4,5-trihydroxybenzoic

acid n-propyl ester, 1,2,3-trihydroxybenzene, butylated hydroxyanisole, 2,6-
Di-tert-Butyl-1-Hydroxy-4-Methylbenzene, alpha-tocopherol acetate, alpha-
tocopherol, gamma-tocopherol, delta-tocopherol, dilauryl thiodipropinate,
isopropyl 2-hydroxy-4-methylthio butanoate, propyl gallate, dodecyl gallate,
gallic acid, octyl gallate, ascorbyl palmitate, lecithin, stearyl citrate,
palmityl
citrate, chlorophyl, pyrogallol, alpha naphthol, ascorbic acid, natural
tocopherol, citric acid, sage extract, rosemary, eugenol, natural antioxidant,

and combinations thereof.



63




20. The fuel composition of claim 18, wherein the polar solvent is selected
from
the group consisting of glycerol, propylene glycol, propylene glycol, polyol,
a
sugar alcohol, and combinations thereof.


21. The fuel composition of claim 18, wherein the nonpolar solvent is selected

from the group consisting of vegetable oil, monoglycerides, diglycerides,
triglycerides, and combinations thereof.


22. The fuel composition of claim 18, wherein the biodiesel is produced from a

source selected from the group consisting of soybean oil, yellow grease, corn
oil, rapeseed oil, coconut oil, peanut oil, palm oil, fish oil, marine oil,
cottonseed oil, mustard seed oil, camelina oil, jojoba oil, hemp oil, tallow,
poultry fat, lard, safflower oil, jatropha oil, algae oil, and sunflower oil.


23. The fuel composition of claim 18, wherein the biodiesel is produced from
rapeseed oil.


24. The fuel composition of claim 18, wherein the biodiesel is produced from
algae oil.


25. The fuel composition of claim 18, wherein the biodiesel is produced from
soybean oil.


26. The fuel composition of claim 25, wherein the first antioxidant is 6-
ethoxy-1,2-
dihydro-2,2,4-trimethylquinoline, the second antioxidant is a natural
antioxidant.


27. The fuel composition of claim 25, wherein the first antioxidant is 6-
ethoxy-1,2-
dihydro-2,2,4-trimethylquinoline, the second antioxidant is a mixture of
propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate, and butylated
hydroxyanisole, and the polar solvent is propylene glycol.



64




28. The fuel composition of claim 25, wherein the first antioxidant is 6-
ethoxy-1,2-
dihydro-2,2,4-trimethylquinoline, the second antioxidant is a mixture of
dodecyl gallate, alpha naphthol, natural tocopherol, and ascorbyl palmitate,
and the polar solvent is propylene glycol.


29. The fuel composition of claim 25, wherein the first antioxidant is 6-
ethoxy-1,2-
dihydro-2,2,4-trimethylquinoline, the second antioxidant is a mixture of 2-6-
di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-butylhydroquinone, and stearyl
citrate, and the nonpolar solvent is corn oil.


30. The fuel composition of claim 25, wherein the first antioxidant is 6-
ethoxy-1,2-
dihydro-2,2,4-trimethylquinoline, the second antioxidant is a mixture of
natural
mixed tocopherols, ascorbyl palmitate, propyl gallate, 2-tert-
butylhydroquinone, and lecithin, and the nonpolar solvent is corn oil.


31. The fuel composition of claim 25, wherein the first antioxidant is 6-
ethoxy-1,2-
dihydro-2,2,4-trimethylquinoline, the second antioxidant is citric acid, and
the
nonpolar solvent is corn oil.


32. The fuel composition of claim 31, wherein the second antioxidant further
comprises 2-tert-butylhydroquinone and 1,2-Propanediol.


33. The fuel composition of claim 25, wherein the first antioxidant is 6-
ethoxy-1,2-
dihydro-2,2,4-trimethylquinoline, the second antioxidant is 2-tert-
butylhydroquinone, and the second nonpolar solvent is corn oil.


34. The fuel composition of claim 18, further comprising an additive selected
from
the group comprising of cetane improvers, ignition accelerators, metal
deactivators, corrosion inhibitors, thermal stabilizers, detergents, antiwear
agents, and demulsifiers.







35. A method of increasing the oxidative stability of a fuel composition, the
method comprising contacting a biodiesel with an antioxidant mixture
comprising at least two antioxidants selected from the group consisting of 2-
tert-butylhydroquinone, 3,4,5-trihydroxybenzoic acid n-propyl ester, 1,2,3-
trihydroxybenzene, butylated hydroxyanisole, 2,6-Di-tert-Butyl-1-Hydroxy-4-
Methylbenzene, alpha-tocopherol acetate, alpha-tocopherol, gamma-
tocopherol, delta-tocopherol, dilauryl thiodipropinate, isopropyl 2-hydroxy-4-
methylthio butanoate, propyl gallate, dodecyl gallate, gallic acid, octyl
gallate,
ascorbyl palmitate, lecithin, stearyl citrate, palmityl citrate, chlorophyl,
pyrogallol, alpha naphthol, ascorbic acid, natural tocopherol, citric acid,
sage
extract, rosemary, eugenol, natural antioxidant, and 6-ethoxy-1,2-dihydro-
2,2,4-trimethylquinoline.

36. The method of claim 35, wherein the biodiesel is produced from a source
selected from the group consisting of soybean oil, yellow grease, corn oil,
rapeseed oil, coconut oil, peanut oil, palm oil, fish oil, marine oil,
cottonseed
oil, mustard seed oil, camelina oil, jojoba oil, hemp oil, tallow, poultry
fat, lard,
safflower oil, jatropha oil, algae oil, and sunflower oil.

37. The method of claim 35, wherein the biodiesel is produced from rapeseed
oil.
38. The method of claim 35, wherein the biodiesel is produced from algae oil.

39. The method of claim 35, wherein the biodiesel is produced from soybean
oil.
40. The method of claim 39, further comprising a polar solvent.

41. The method of claim 40, wherein the antioxidant mixture comprises 6-ethoxy-

1,2-dihydro-2,2,4-trimethylquinoline, propyl gallate, dilauryl
thiodipropionate,
ascorbyl palmitate, and butylated hydroxyanisole, and the polar solvent is
propylene glycol.

66




42. The method of claim 40, wherein the antioxidant mixture comprises 6-ethoxy-

1,2-dihydro-2,2,4-trimethylquinoline, dodecyl gallate, alpha naphthol, natural

tocopherol, and ascorbyl palmitate, and the polar solvent is propylene glycol.


43. The method of claim 39, further comprising a nonpolar solvent.


44. The method of claim 43, wherein the antioxidant mixture comprises 6-ethoxy-

1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-tert-butyl-4-methylphenol,
pyrogallol, 2-tert-butylhydroquinone, and stearyl citrate, and the nonpolar
solvent is corn oil.


45. The method of claim 43, wherein the antioxidant mixture comprises 6-ethoxy-

1,2-dihydro-2,2,4-trimethylquinoline, natural mixed tocopherols, ascorbyl
palmitate, propyl gallate, 2-tert-butylhydroquinone, and lecithin, and the
nonpolar solvent is corn oil.


46. The method of claim 43, wherein the antioxidant mixture comprises 6-ethoxy-

1,2-dihydro-2,2,4-trimethylquinoline and citric acid, and the nonpolar solvent
is
corn oil.


47. The method of claim 46, wherein the antioxidant mixture further comprises
2-
tert-butylhydroquinone and 1,2-Propanediol.


48. The method of claim 43, wherein the antioxidant mixture comprises 6-ethoxy-

1,2-dihydro-2,2,4-trimethylquinoline, 2-tert-butylhydroquinone, and the
nonpolar solvent is corn oil.


49. The method of claim 35, further comprising contacting an additive with the

biodiesel and the antioxidant mixture.


50. The method of claim 49, wherein the additive is selected from the group
comprising of cetane improvers, ignition accelerators, metal deactivators,




corrosion inhibitors, thermal stabilizers, detergents, antiwear agents, and
demulsifiers.


51. The method of claim 35, wherein the antioxidant mixture comprises 6-ethoxy-

1,2-dihydro-2,2,4-trimethylquinoline and a second antioxidant and the fuel
composition has less than 2.8 mg/100 ml of filterable insolubles.


52. The method of claim 35, wherein the antioxidant mixture comprises 6-ethoxy-

1,2-dihydro-2,2,4-trimethylquinoline and a second antioxidant and the fuel
composition has less than 4.3 mg/100 ml of adherent insolubles.


53. The method of claim 35, wherein the antioxidant mixture comprises 6-ethoxy-

1,2-dihydro-2,2,4-trimethylquinoline and a second antioxidant and the fuel
composition has less than 6.8 mg/100 ml of total insolubles.


54. The method of claim 35, wherein the fuel has a kinematic viscosity at 40 C
of
from about 4.00 mm2/sec to about 5.0 mm2/sec.


55. The method of claim 35, wherein the fuel has an acid value of from about
0.1
mg KOH/g to about 0.75 mg KOH/g.


56. The method of claim 35, wherein the fuel has a density at 20°C of
from about
0.865 g/cm3 to about 0.884 g/cm3.


57. The method of claim 35, wherein the fuel has a cold filter plugging point
(CFPP) of from about -1 °C to about -10°C.


58. The method of claim 35, wherein the fuel has a sulphated ash percent by
mass of from about 0.001 % by mass to about 0.002% by mass.



68

Description

CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920

BIODIESEL FUEL COMPOSITIONS HAVING INCREASED
OXIDATIVE STABILITY

FIELD OF THE INVENTION
[0001] The present invention relates to biodiesel fuel compositions that
have improved oxidation stability. More specifically, the biodiesel fuel
compositions
include at least one antioxidant that increases the oxidative stability of the
fuel.
BACKGROUND OF THE INVENTION
[0002] The use and production of biodiesel as an alternative to vehicle
fuel, heating fuel, and engine fuel has increased in recent years due to
concerns with
limited resources of petroleum based fuels. Biodiesel is typically produced
from the
transesterification of, for example, vegetable oils, animal fats, and used
cooking oils.
[0003] Biodiesel, as it has a higher content of unsaturated fatty acid esters,
easily oxidizes in the presence of oxygen, UV light, heat, trace metals, such
as iron
and copper, among others. The products formed from this oxidation give rise to
sediment and gum formation within the fuel and lead to corrosion and plugging
in
injection pumps and/or fuel lines in engines, heaters, and/or machines which
utilize
biodiesel as a fuel source.
[0004] As such, there is a need for a biodiesel fuel composition having
improved oxidation stability that reduces or eliminates sedimentation and gum
formation within the fuel and as such reduces or eliminates corrosion and
plugging in
injection pumps and/or fuel lines in engines.

SUMMARY OF THE INVENTION
[0005] One aspect of the present invention provides a fuel composition
comprising a biodiesel from a source other than rapeseed oil, frying oil,
sunflower oil,
and beef tallow and at least one antioxidant. The antioxidant is selected from
the
group consisting of 3,4,5-trihydroxybenzoic acid n-propyl ester, 1,2,3-
trihydroxybenzene, butylated hydroxyanisole, 2,6-Di-tert-Butyl-l-Hydroxy-4-
Methylbenzene, alpha-tocopherol acetate, alpha-tocopherol, gamma-tocopherol,
delta-tocopherol, dilauryl thiodipropinate, isopropyl 2-hydroxy-4-methylthio
butanoate, propyl gallate, dodecyl gallate, gallic acid, octyl gallate,
ascorbyl


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WO 2007/062304 PCT/US2006/060920
palmitate, lecithin, stearyl citrate, paimityl citrate, chlorophyl,
pyrogallol, alpha
naphthol, ascorbic acid, natural tocopherol, citric acid, sage extract,
rosemary,
eugenol, and 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline.
[0006] Another aspect of the invention provides a fuel composition
comprising a biodiesel and an antioxidant mixture. The mixture comprises at
least
two antioxidants selected from the group consisting of 2-tert-
butylhydroquinone,
3,4,5-trihydroxybenzoic acid n-propyl ester, 1,2,3-trihydroxybenzene,
butylated
hydroxyanisole, 2,6-Di-tert-Butyl-1-Hydroxy-4-Methylbenzene, alpha-tocopherol
acetate, alpha-tocopherol, gamma-tocopherol, delta-tocopherol, dilauryl
thiodipropinate, isopropyl 2-hydroxy-4-methylthio butanoate, propyl gallate,
dodecyl
gallate, gallic acid, octyl gallate, ascorbyl palmitate, lecithin, stearyl
citrate, paimityl
citrate, chlorophyl, pyrogallol, alpha naphthol, ascorbic acid, natural
tocopherol, citric
acid, sage extract, rosemary, eugenol, and 6-ethoxy-1,2-dihydro-2,2,4-
trimethylquinoline.
[0007] Yet another aspect of the invention provides a fuel composition
comprising a first antioxidant having the Formula (I),

R4
R5 R3
R2
H R (I)

wherein:
R1, R2, R3 and R4 are independently selected from the group
consisting of hydrogen and an alkyl group having from 1 to
about 6 carbons; and
R5 is an alkoxy group having from I to about 12 carbons
a second antioxidant not having the Formula (I), a polar solvent, and a
nonpolar
solvent, wherein the two solvents form a homogenous liquid.
[0008] A further aspect of the invention provides a method of increasing
the oxidative stability of a fuel composition comprising contacting a
biodiesel and an
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antioxidant mixture comprising at least two antioxidants. The two antioxidants
are
selected from the group consisting of 2-tert-butylhydroquinone, 3,4,5-
trihydroxybenzoic acid n-propyl ester, 1,2,3-trihydroxybenzene, butylated
hydroxyanisole, 2,6-Di-tert-Butyl-l-Hyd roxy-4- M ethyl benzene, alpha-
tocopherol
acetate, alpha-tocopherol, gamma-tocopherol, delta-tocopherol, dilauryl
thiodipropinate, isopropyl 2-hydroxy-4-methylthio butanoate, propyl gallate,
dodecyl
gallate, gallic acid, octyl gallate, ascorbyl palmitate, lecithin, stearyl
citrate, palmityl
citrate, chlorophyl, pyrogallol, alpha naphthol, ascorbic acid, natural
tocopherol, citric
acid, sage extract, rosemary, eugenol, and 6-ethoxy-1,2-dihydro-2,2,4-
trimethylquinoline.
[0009] Other aspects and features of the invention will be in part apparent
and in part pointed out hereinafter.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0010] Advantageously, the present invention provides biodiesel fuel
compositions that have improved oxidation stability. The fuel compositions of
the
invention comprise a biodiesel and at least one antioxidant that increases the
oxidative stability of the fuel. The fuel compositions of the present
invention, as
such, not only have improved oxidative stability, but also have longer
induction
times, lower amounts of insolubles, and lower peroxide values.

I. Biodiesel
[0011] The fuel composition of the invention includes a biodiesel.
Generally speaking, a biodiesel suitable for use in the invention is typically
an ester,
such as a mono-alkyl ester, of long chain fatty acids derived from a lipid
source. The
lipid source may be naturally occurring, such as a lipid derived from a plant
or
animal, or it may be synthetically produced. In one embodiment, the biodiesel
may
be produced from vegetable oil, spent cooking oil, or animal fat. In one
embodiment,
the biodiesel is produced from a vegetable oil. In another embodiment, the
biodiesel
is produced from a vegetable oil selected from the group consisting of soybean
oil,
corn oil, rapeseed oil, coconut oil, peanut oil, palm oil, cottonseed oil,
sunflower oil,
mustard seed oil, camelina oil, jojoba oil, safflower oil, and hemp oil. Other
vegetable oils may also be used without departing from the scope of the
invention.

3


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In an exemplary embodiment, the biodiesel is produced from soybean oil. In
another
exemplary embodiment, the biodiesel is produced from rapeseed oil. In another
embodiment, the biodiesel is produced from plant oil, such as jatropha oil and
algae
oil. In a further embodiment, the biodiesel is produced from spent cooking
oil, such
as used frying oil. In yet another embodiment, the biodiesel is produced from
animal
fat selected from the group consisting of tallow, poultry fat, and lard. In
still another
embodiment, the biodiesel may be produced from a yellow grease. In yet another
embodiment, the biodiesel may be produced from a fish oil, such as menhaden
oil,
anchovy oil, and mackerel oil, among others. In a further embodiment, the
biodiesel
may be produced from marine oil, such as whale oil or shark oil. As will be
appreciated by the skilled artisan, the biodiesel may also be produced from a
combination of lipids derived from different sources. For example, the
biodiesel may
be produced from soybean oil and animal fat.
[0012] A variety of methods generally known in the art may be used to
make the biodiesel of the present invention from any lipid sources known in
the art or
identified herein. In general, biodiesel is produced through the
transesterifcation of
vegetable oils, spent cooking oils, or animal fats. Such methods typically
include
base catalyzed transesterification of the oil or fat with an alcohol, and
direct acid
catalyzed esterification of the oil or fat with methanol, conversion of the
oil or fat to
fatty acids, and then to alkyl esters with an acid catalyst. In a base
catalyzed
transesterification process, an oil or fat is reacted with an alcohol, such as
methanol
or ethanol, in the presence of a catalyst, such as sodium hydroxide or
potassium
hydroxide, to produce glycerine and methyl or ethyl esters. The glycerin is
then
separated from the biodiesel. Once the separation of glycerin and biodiesel is
complete, the alcohol is removed by distillation. The glycerin is generally
neutralized
with an acid and sent to storage as crude glycerin. Once separated from the
glycerin, the biodiesel is generally purified by washing it gently with warm
water (the
methyl ester wash) to remove residual catalysts or soaps, dried and sent to
storage.
[0013] The present invention also contemplates blends of biodiesels and
petroleum based diesel fuels. It will be appreciated by the skilled artisan
that the
amount of biodiesel and petroleum diesel present in the fuel composition of
the
present invention can and will vary depending upon the fuel's intended use.
For
example, the fuel composition may comprise from about 10% to about 40% by

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weight biodiesel and from about 60% to about 90% by weight petroleum based
diesel. In another embodiment, the fuel composition may comprise from about
20%
to about 30% by weight biodiesel and from about 70% to about 80% by weight
petroleum based diesel. In yet another embodiment, the fuel composition
comprises
about 20% by weight biodiesel and about 80% by weight petroleum based diesel,
which is known as B20.

11. Antioxidants
[0014] The fuel composition of the invention also includes one or more
antioxidants. Generally speaking, antioxidants suitable for use in the present
invention inhibit the oxidation process and thus, enhance the fuel
composition's
oxidative stability and reduce insolubles formation. In particular, applicants
have
found that by contacting at least one antioxidant with a biodiesel to form a
biodiesel
fuel composition, the fuel has increased oxidative stability. In addition, to
increasing
the oxidative stability of the fuel, the antioxidant will further decrease the
NOx, carbon
monoxide and other fuel emissions. Those skilled in the art will appreciate
that
different antioxidants may be used depending on the type of biodiesel to be
stabilized.

a. Individual Antioxidants
[0015] In one embodiment, the antioxidant may be selected from the group
comprised of butylated hydroxyanisole (BHA); butylated hydroxytoluene;
gailates
such as octyl gallate, dodecyl gallate, and 3,4,5-trihydroxybenzoic acid n-
propyl ester
(propyl gallate); 1,2,3-trihydroxybenzene (pyrogallol); gallic acid; fatty
acid esters
including, but not limited to, methyl esters such as methyl linoleate, methyl
oleate,
methyl stearate, and other esters such as ascorbic palmitate; disulfiram;
tocopherols,
such as gamma-tocopherol, delta-tocopherol alpha-tocopherol acetate, and alpha-

tocopherol marketed under the name COPHEROL 1300 by the company Henkel,
and tocopherol derivatives and precursors, such as Coviox T-50 by the company
Cognis; deodorized extract of rosemary; propionate esters and thiopropionate
esters
such as isopropyl 2-hydroxy-4-methylthio butanoate, lauryl thiodipropionate,
or
dilauryl thiodipropionate; beta-lactoglobulin; ascorbic acid; amino acids such
as
phenylalanine, cysteine, tryptophan, methionine, glutamic acid, glutamine,
arginine,



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leucine, tyrosine, lysine, serine, histidine, threonine, asparagine, glycine,
aspartic
acid, isoleucine, valine, and alanine; 2,2,6,6-tetramethylpiperidinooxy, also
referred
to as tanan; 2,2,6,6-tetramethyl-4-hydroxypiperidine-l-oxyl, also referred to
as tanol;
dimethyl-p-phenylaminophenoxysilane; di-p-anisylazoxides; p-
hydroxydiphenylamine, and carbonates, phthalates, and adipates thereof; and
diludin, a 1,4-dihydropyridine derivative.
[0016] In another embodiment, the antioxidant may be selected from the
group comprising oil-soluble antioxidants, including, but not limited to
ascorbyl
palmitate, butylated hydroxytoluene, lecithin, alpha-tocopherol, phenyl-alpha-
naphthylamine, hydroquinone, nordihydroguaiaretic acid, and rosemary extract.
[0017] In a further embodiment, the antioxidant may be a synthetic or
natural antioxidants selected from the group comprising of Vitamin C and
derivatives
(ascorbic acid); Vitamin E and derivatives (tocopherols, tocotrienols,
acetate); sage
extract; eugenol; rosemary; flavonoids and derivatives (including catechins);
phenolic
acids and derivatives; 2-tert-butylhydroquinone (TBHQ); mixtures of TBHQ,
glyceryl
oleate, propylene glycol, vegetable oil, and citric acid such as TENOX 20 and
TENOX 21 by the company Eastman Chemical Company; imidazolidinyl urea,
quaternary ammoniums, diazolidinyl urea; erythorbic acid; sodium erythorbate,
lactic
acid, calcium ascorbate, sodium ascorbate, potassium ascorbate, ascorbyl
stearate,
erythorbin acid; sodium erythorbin; butylhydroxinon; sodium or potassium or
calcium
or magnesium lactate; citric acid; sodium, monosodium, disodium or trisodium
citrates; potassium, monopotassium or tripotassium citrate; stearyl citrate;
palmityl
citrate; tartaric acid; sodium, monosodium or disodium tartrates; potassium,
monopotassium tartrate or dipotassium tartrate; sodium potassium tartrate;
phosphoric acid; sodium, monosodium, disodium or trisodium phosphates;
potassium, monopotassium, dipotassium and tripotassium phosphates; stannous
chloride; chlorophyl; lecithin; nordihydroguaiaretic acid (NDGA); alcoholic
esters of
the gallates; ascorbyl stearate; 2-tertiarybutyl-4-hydroxyanisole; 3-
tertiarybutyl-4-
hydroxyanisole; 1-cysteine hydrochloride; gum guaiacum; lecithin citrate;
monoglyceride citrate; monoisopropyl citrate; Ethylenediaminetetraacetic acid;
2,6-
di-tert-butyl-4-hydroxymethylphenol; 2-6-di-tert-butyl-4-methylphenol (BHT)
and t-
tert-butyl-4-methylphenol (t-BHT); polyphosphates; trihydroxy butyrophenone;
anoxomer; and combinations thereof such as RENDOX by the company Kemin

6


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Industries which contains a mixture of propylene glycol, mono- and
diglycerides,
butylated hydroxyanisole and citric acid. Other synthetic antioxidants include
the
antioxidants marketed under the names BIOCAPS GP, BIOCAPS A-70, BIOCAPS
TL, BIOCAPS ER, BIOCAPS PA, AP, CONTROX VP, COPHEROL 1300, DADEX,
VANLUBE 848, IONOL and BAYNOX.
[0018] In yet another embodiment, the antioxidant may be a water soluble
antioxidants selected from the group comprising of ascorbic acid, sodium
metabisulfite, sodium bisulfite, sodium thiosulfite, sodium formaldehyde
sulfoxylate,
isoascorbic acid, thioglyerol, thiosorbitol, thiourea, thioglycolic acid,
cysteine
hydrochloride, 1,4-diazobicyclo-(2,2,2)-octane, malic acid, fumaric acid, and
Iicopene.
[0019] In an exemplary embodiment, the antioxidant may be a substituted
1,2-dihydroquinoline compounds. Substituted 1,2-dihydroquinoline compounds
suitable for use in the invention generally correspond to formula (I):

R4
R5 R3
R2

N R'
H
(I)
wherein:
R1, R2, R3 and R4 are independently selected from the group
consisting of hydrogen and an alkyl group having from 1 to
about 6 carbons;
R5 is an alkoxy group having from 1 to about 12 carbons.
[0020] In another embodiment, the substituted 1,2-dihydroquinoline will
have formula (I) wherein:
R', R2, R3 and R4 are independently selected from the group
consisting of hydrogen and an alkyl group having from 1 to
about 4 carbons; and
R5 is an alkoxy group having from 1 to about 4 carbons.
7


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[0021] In one preferred embodiment, the substituted 1,2-dihydroquinoline
will be 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline having the formula:

H
N
6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, commonly known as ethoxyquin,
is
sold under the trademark SANTOQUIN or AGRADO . The present invention also
encompasses salts of ethoxyquin and other compounds having formula (I).
Ethoxyquin and other compounds having formula (I) may be purchased
commercially
from Novus International, Inc. or made in accordance with methods generally
known
in the art, for example, as detailed in U.S. Patent No. 4,772,710, which is
hereby
incorporated by reference in its entirety.

b. Antioxidant Formulations
[0022] In one embodiment, the antioxidant of the present invention is an
antioxidant mixture comprising at least two antioxidants as described in Part
11(a). In
another embodiment, the antioxidant mixture comprises a first antioxidant of
substituted 1,2-dihydroquinoline compound of Formula (I) and a second
antioxidant
that does not have the Formula (I). The second antioxidant may be any of the
antioxidants described in Part 11(a) above other than the antioxidant of
Formula (I).
In other embodiments, the antioxidant mixture may include at least three
different
antioxidants. In additional embodiments, the combination may include four or
more
antioxidants. Non-limiting examples of suitable antioxidant mixtures are set-
forth in
Table A. A preferred composition comprises 6-ethoxy-1,2-dihydro-2,2,4-
trimethylquinoline (ethoxyquin) and 2-tert-butylhydroquinone. Other preferred
compositions comprise 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, as well
as one
or more of the following: 2-tert-butylhydroquinone, 3,4,5-trihydroxybenzoic
acid n-
propyl ester, 1,2,3-trihydroxybenzene, butylated hydroxyanisole, 2,6-Di-tert-
Butyl-l-

8


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Hydroxy-4-Methylbenzene, alpha-tocopherol acetate, alpha-tocopherol, gamma-
tocopherol, delta-tocopherol, dilauryl thiodipropinate, isopropyl 2-hydroxy-4-
methylthio butanoate, propyl gallate, dodecyl gallate, gallic acid, octyl
gallate,
ascorbyl palmitate, lecithin, stearyl citrate, palmityl citrate, chlorophyl,
pyrogallol,
alpha naphthol, ascorbic acid, natural tocopherol, citric acid, sage extract,
rosemary,
and eugenol.

Table A. Formulations of the antioxidant mixtures.
First Antioxidant Second or Antioxidant Mixture
6-ethoxy-1,2-dihydro-2,2,4- 2-tert-butylhydroquinone
trimeth I uinoline
6-ethoxy-1,2-dihydro-2,2,4- propyl gallate, dilauryl thiodipropionate,
trimethylquinoline ascorbyl palmitate, and butylated
h drox anisole
6-ethoxy-1,2-dihydro-2,2,4- dodecyl gallate, alpha naphthol, natural
trimeth I uinoline tocopherol, and ascorbyl palmitate
6-ethoxy-1,2-dihydro-2,2,4- 2-6-di-tert-butyl-4-methylphenol,
trimethylquinoline pyrogallol, 2-tert-butylhydroquinone, and
stearyl citrate
6-ethoxy-1,2-dihydro-2,2,4- natural mixed tocopherols, ascorbyl
trimethylquinoline palmitate, propyl gallate, 2-tert-
but Ih dro uinone, and lecithin
6-ethoxy-1,2-dihydro-2,2,4- citric acid
trimeth I uinoline
6-ethoxy-1,2-dihydro-2,2,4- citric acid, 2-tert-butylhydroquinone and
trimeth I uinoline 1,2-Pro anediol
6-ethoxy-1,2-dihydro-2,2,4- butylated hydroxyanisole, 2,6-Di-tert-
trimethylquinoline Butyl-1-Hydroxy-4-Methylbenzene, and
2-tert-but Ih droquinone

[0023] Other suitable combinations of antioxidants are detailed in the
examples.

c. Solvents
[0024] The antioxidant composition may further comprise a polar solvent.
Generally speaking, the polar solvent solubilizes the water-soluble
antioxidants.
Suitable examples of polar solvents include, but are not limited to, glycerol,
isopropyl
alcohol, ethyl alcohol, propylene glycol, erythritol, xylitol, sorbitol,
maltitol, mannitol,
water, polyol, or combinations thereof. In one embodiment, the polar solvent
is

9


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WO 2007/062304 PCT/US2006/060920
glycerol. In another embodiment, the polar solvent is propylene glycol. The
concentration of the polar solvent will vary depending upon the combination of
antioxidants in the composition. In general, the percent by volume of the
polar
solvent may range from about 5% to about 50%. The percent by volume of
glycerol
may be about 5%, 10%, 15%, 20%, or 25%. The percent by volume of propylene
glycol may be about 5%, 10%, 15%, 20%, or 25%.
[0025] The antioxidant composition may further comprise a nonpolar
solvent. In general, the nonpolar solvent solubilizes the lipid-soluble
antioxidants,
and helps make the antioxidant composition miscible in an oil or fat sample.
In one
preferred embodiment, the nonpolar solvent is a biodiesel as described in Part
I
above. Suitable examples of other nonpolar solvents include, but are not
limited to,
vegetable oils, monoglycerides, diglycerides, triglycerides, and combinations
thereof.
The vegetable oil may be corn oil, soybean oil, canola oil, cottonseed oil,
palm oil,
peanut oil, safflower oil, and sunflower oil. The monoglycerides and
diglycerides
may be isolated and distilled from vegetable oils, or the monoglycerides and
diglycerides may be synthesized chemically via an esterification reaction. In
one
embodiment, the nonpolar solvent may be corn oil. In another embodiment, the
nonpolar solvent may comprise corn oil and monoglycerides. The concentration
of
the nonpolar solvent will vary depending upon the combination of antioxidants
in the
composition. In general, the percent by volume of the nonpolar solvent may
range
from about 5% to about 50%. The percent by volume of monoglycerides may be
10%, 15%, 20%, or 25%. The percent by volume of corn oil may be 5%, 10%, 15%,
20%, or 25%. In one embodiment, percent by volume of corn oil may be 15-25%.
In
another embodiment, the percent by volume of monoglycerides may be 15-20% and
the percent by volume of corn oil may be about 5-10%.

lll. Fuel Compositions
[0026] The fuel compositions comprise biodiesel, one or more antioxidants
and optionally, a polar solvent, a nonpolar solvent, and/or a petroleum based
diesel.
In one embodiment, the fuel composition of the invention comprises a biodiesel
and
at least one antioxidant that increases the oxidative stability of the fuel
composition.
In this embodiment, the biodiesel may be any of the biodiesels described in
Part I in
combination with any of the antioxidants described in Part II. In an
alternative



CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
embodiment, the fuel composition comprises any of the biodiesel as described
in
Part I of the specification other than those produced from undistilled or
distilled
rapeseed oil, frying oil, sunflower oil, and beef tallow and at least one
antioxidant as
described in Part II of the specification above. Examples of exemplary fuel
compositions are presented in Table B below. Alternatively, each fuel
composition
detailed in Table B may also include 6-ethoxy-1,2-dihydro-2,2,4-
trimethylquinoline.

TABLE B
Biodiesel Raw Material Antioxidants
Soybean Oil 3,4,5-trih drox benzoic acid n- ro I ester
Soybean Oil 1,2,3-trih drox benzene
Soybean Oil Butylated H drox anisole
Soybean Oil t-tert-but I-4-meth Iphenol
Soybean Oil 2,6-Di-tert-But I-1-H drox -4-Meth Ibenzene
Soybean Oil 6-ethox -1,2-dih dro-2,2,4-trimeth I uinoline
Soybean Oil al ha-toco herol acetate
Soybean Oil al ha-toco herol
Soybean Oil gamma-tocopherol
Soybean Oil delta-tocopherol
Soybean Oil dilauryl thiodi ro ionate
Soybean Oil iso ro I 2-h drox -4-meth Ithio butanoate
Soybean Oil dodecyl gallate
Soybean Oil gailic acid
Soybean Oil octyl gailate
Soybean Oil ascorbyl palmitate
Soybean Oil lecithin
Soybean Oil stearyl citrate
Soybean Oil palmityl citrate
Soybean Oil Chlorophyll
Soybean Oil Propyl gallate
Soybean Oil P ro allol
Soybean Oil Alpha naphthol
Soybean Oil Ascorbic acid
Soybean Oil Natural tocopherols
Soybean Oil Citric acid
Soybean Oil Sage extract
Soybean Oil Rosemary
Soybean Oil eugenol
Corn Oil 3,4,5-trih drox benzoic acid n- rop l ester
Corn Oil 1,2,3-trih drox benzene
Corn Oil But lated H drox anisole
Corn Oil t-tert-but I-4-meth Iphenol
Corn Oil 2,6-Di-tert-But I-1-H drox -4-Meth Ibenzene
Corn Oil 6-ethox -1,2-dih dro-2,2,4-trimeth Iquinoline
11


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TABLE B
Biodiesel Raw Material Antioxidants
Corn Oil al ha-toco herol acetate
Corn Oil al ha-toco herol
Corn Oil amma-toco herol
Corn Oil delta-tocopherol
Corn Oil dilauryl thiodi ro ionate
Corn Oil iso ro I 2-h drox -4-meth Ithio butanoate
Corn Oil dodecyl gallate
Corn Oil gallic acid
Corn Oil octyl gallate
Corn Oil ascorbyl palmitate
Corn Oil lecithin
Corn Oil stearyl citrate
Corn Oil palmityl citrate
Corn Oil chloro h I
Corn Oil Propyl gallate
Corn Oil P ro allol
Corn Oil Alpha naphthol
Corn Oil Ascorbic acid
Corn Oil Natural tocopherols
Corn Oil Citric acid
Corn Oil Sage extract
Corn Oil Rosemary
Corn Oil eugenol
Coconut Oil 3,4,5-trih drox benzoic acid n- ro I ester
Coconut Oil 1,2,3-trih drox benzene
Coconut Oil Butylated H drox anisole
Coconut Oil t-tert-but I-4-meth I henol
Coconut Oil 2,6-Di-tert-But I-1-H drox -4-Meth Ibenzene
Coconut Oil 6-ethox -1,2-dih dro-2,2,4-trimeth I uinoline
Coconut Oil al ha-toco herol acetate
Coconut Oil al ha-toco herol
Coconut Oil gamma-tocopherol
Coconut Oil delta-tocopherol
Coconut Oil dilauryl thiodipropionate
Coconut Oil iso ro I 2-h drox -4-meth Ithio butanoate
Coconut Oil dodecyl gallate
Coconut Oil gallic acid
Coconut Oil octyl gallate
Coconut Oil ascorbyl palmitate
Coconut Oil lecithin
Coconut Oil stearyl citrate
Coconut Oil paimit I citrate
Coconut Oil chloro h I
Coconut Oil Propyl gallate
Coconut Oil P ro allol

12


CA 02629613 2008-05-13
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TABLE B
Biodiesel Raw Material Antioxidants
Coconut Oil Alpha naphthol
Coconut Oil Ascorbic acid
Coconut Oil Natural tocopherols
Coconut Oil Citric acid
Coconut Oil Sage extract
Coconut Oil Rosemary
Coconut Oil eugenol
Peanut Oil 3,4,5-trih drox benzoic acid n- ro I ester
Peanut Oil 1,2,3-trih drox benzene
Peanut Oil Butylated H drox anisole
Peanut Oil t-tert-but I-4-meth I henol
Peanut Oil 2,6-Di-tert-But I-1-H drox -4-Meth Ibenzene
Peanut Oil 6-ethox -1,2-dih dro-2,2,4-trimeth I uinoline
Peanut Oil alpha-toco herol acetate
Peanut Oil al ha-toco herol
Peanut Oil gamma-tocopherol
Peanut Oil delta-tocopherol
Peanut Oil dilau I thiodipropionate
Peanut Oil iso ro I 2-h drox -4-meth Ithio butanoate
Peanut Oil dodecyl gallate
Peanut Oil gallic acid
Peanut Oil octyl gallate
Peanut Oil ascorbyl palmitate
Peanut Oil lecithin
Peanut Oil stearyl citrate
Peanut Oil paimityl citrate
Peanut Oil chloro h I
Peanut Oil Propyl gallate
Peanut Oil P ro allol
Peanut Oil Alpha naphthol
Peanut Oil Ascorbic acid
Peanut Oil Natural tocopherols
Peanut Oil Citric acid
Peanut Oil Sage extract
Peanut Oil Rosemary
Peanut Oil eugenol
Palm Oil 3,4,5-trih drox benzoic acid n- ro I ester
Palm Oil 1,2,3-trih drox benzene
Palm Oil Butylated H drox anisole
Palm Oil t-tert-but I-4-meth Iphenol
Palm Oil 2,6-Di-tert-But I-1-H drox -4-Meth Ibenzene
Palm Oil 6-ethox -1,2-dih dro-2,2,4-trimeth Iquinoline
Palm Oil al ha-toco herol acetate
Palm Oil al ha-toco herol
Palm Oil amma-toco herol
13


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WO 2007/062304 PCT/US2006/060920
TABLE B
Biodiesel Raw Material Antioxidants
Palm Oil delta-tocopherol
Palm Oil dilauryl thiodi ro ionate
Palm Oil iso ro I 2-h drox -4-meth Ithio butanoate
Palm Oil dodecyl gallate
Palm Oil gallic acid
Palm Oil octyl gallate
Palm Oil ascorbyl paimitate
Palm Oil lecithin
Palm Oil stearyl citrate
Palm Oil paimityl citrate
Palm Oil chloro h I
Palm Oil Propyl gallate
Palm Oil P ro allol
Palm Oil Alpha naphthol
Palm Oil Ascorbic acid
Palm Oil Natural tocopherols
Palm Oil Citric acid
Palm Oil Sage extract
Palm Oil Rosemary
Palm Oil eugenol
Fish Oil 3,4,5-trih drox benzoic acid n-propyl ester
Fish Oil 1,2,3-trih drox benzene
Fish Oil Butylated H drox anisole
Fish Oil t-tert-but I-4-meth I henol
Fish Oil 2,6-Di-tert-But I-1-H drox -4-Meth Ibenzene
Fish Oil 6-ethox -1,2-dih dro-2,2,4-trimeth I uinoline
Fish Oil al ha-toco herol acetate
Fish Oil al ha-toco herol
Fish Oil gamma-tocopherol
Fish Oil delta-tocopherol
Fish Oil dilauryl thiodi ro ionate
Fish Oil iso ro I 2-h drox -4-meth Ithio butanoate
Fish Oil dodecyl allate
Fish Oil gallic acid
Fish Oil octyl gallate
Fish Oil ascorbyl palmitate
Fish Oil lecithin
Fish Oil stearyl citrate
Fish Oil palmityl citrate
Fish Oil chloro h I
Fish Oil Propyl gailate
Fish Oil P ro allol
Fish Oil Alpha naphthol
Fish Oil Ascorbic acid
Fish Oil Natural tocopherols
14


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TABLE B
Biodiesel Raw Material Antioxidants
Fish Oil Citric acid
Fish Oil Sage extract
Fish Oil Rosemary
Fish Oil eugenol
Lard 3,4,5-trih drox benzoic acid n- ro I ester
Lard 1,2,3-trih drox benzene
Lard Butylated H drox anisole
Lard t-tert-but I-4-meth I henol
Lard 2,6-Di-tert-But I-1-H drox -4-Meth Ibenzene
Lard 6-ethox -1,2-dih dro-2,2,4-trimeth I uinoline
Lard al ha-toco herol acetate
Lard al ha-toco herol
Lard gamma-tocopherol
Lard delta-tocopherol
Lard dilauryl thiodi ro ionate
Lard iso ro I 2-h drox -4-meth Ithio butanoate
Lard dodecyl gailate
Lard allic acid
Lard octyl allate
Lard ascorbyl aimitate
Lard lecithin
Lard stearyl citrate
Lard palmityl citrate
Lard chloro h I
Lard Propyl gallate
Lard P ro allol
Lard Alpha naphthol
Lard Ascorbic acid
Lard Natural tocopherols
Lard Citric acid
Lard Sage extract
Lard Rosemary
Lard eugenol
Mustard Seed Oil 3,4,5-trih drox benzoic acid n-propyl ester
Mustard Seed Oil 1,2,3-trih drox benzene
Mustard Seed Oil Butylated H drox anisole
Mustard Seed Oil t-tert-but I-4-meth Iphenol
Mustard Seed Oil 2,6-Di-tert-Bu I-1-H drox -4-Meth Ibenzene
Mustard Seed Oil 6-ethox -1,2-dih dro-2,2,4-trimeth Iquinoline
Mustard Seed Oil alpha-tocopherol acetate
Mustard Seed Oil alpha-tocopherol
Mustard Seed Oil gamma-tocopherol
Mustard Seed Oil delta-tocopherol
Mustard Seed Oil dilauryl thiodi ro ionate
Mustard Seed Oil iso ro I 2-h drox -4-meth Ithio butanoate


CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
TABLE B
Biodiesel Raw Material Antioxidants
Mustard Seed Oil dodecyl gallate
Mustard Seed Oil allic acid
Mustard Seed Oil octyl gallate
Mustard Seed Oil ascorbyl palmitate
Mustard Seed Oil lecithin
Mustard Seed Oil stearyl citrate
Mustard Seed Oil paimit I citrate
Mustard Seed Oil chloro h I
Mustard Seed Oil Propyl allate
Mustard Seed Oil P ro allol
Mustard Seed Oil Alpha naphthol
Mustard Seed Oil Ascorbic acid
Mustard Seed Oil Natural tocopherols
Mustard Seed Oil Citric acid
Mustard Seed Oil Sage extract
Mustard Seed Oil Rosemary
Mustard Seed Oil eugenol
Camelina Oil 3,4,5-trih drox benzoic acid n-propyl ester
Camelina Oil 1,2,3-trih drox benzene
Camelina Oil Butylated H drox anisole
Camelina Oil t-tert-but I-4-meth I henol
Camelina Oil 2,6-Di-tert-But I-1-H drox -4-Meth Ibenzene
Camelina Oil 6-ethox -1,2-dih dro-2,2,4-trimeth Iquinoline
Camelina Oil al ha-toco herol acetate
Camelina Oil al ha-toco herol
Camelina Oil gamma-tocopherol
Camelina Oil delta-tocopherol
Camelina Oil dilauryl thiodi ro ionate
Camelina Oil iso ro I 2-h drox -4-meth Ithio butanoate
Camelina Oil dodecyl gallate
Camelina Oil allic acid
Camelina Oil octyl gallate
Camelina Oil ascorbyl palmitate
Camelina Oil lecithin
Camelina Oil stearyl citrate
Camelina Oil palmityl citrate
Camelina Oil chloro h I
Camelina Oil Propyl gallate
Camelina Oil P ro allol
Camelina Oil Alpha naphthol
Camelina Oil Ascorbic acid
Camelina Oil Natural tocopherols
Camelina Oil Citric acid
Camelina Oil Sage extract
Camelina Oil Rosemary

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TABLE B
Biodiesel Raw Material Antioxidants
Camelina Oil eugenol
Jojoba Oil 3,4,5-trih drox benzoic acid n- ro I ester
Jojoba Oil 1,2,3-trih drox benzene
Jojoba Oil Butylated H drox anisole
Jojoba Oil t-tert-but I-4-meth I henol
Jojoba Oil 2,6-Di-tert-But I-1-H drox -4-Meth Ibenzene
Jojoba Oil 6-ethox -1,2-dih dro-2,2,4-trimeth Iquinoline
Jojoba Oil al ha-toco herol acetate
Jojoba Oil al ha-toco herol
Jojoba Oil gamma-tocopherol
Jojoba Oil delta-tocopherol
Jojoba Oil dilauryl thiodi ro ionate
Jojoba Oil iso rop I 2-h drox -4-meth Ithio butanoate
Jojoba Oil dodecyl gallate
Jojoba Oil allic acid
Jojoba Oil octyl allate
Jojoba Oil ascorbyl palmitate
Jojoba Oil lecithin
Jojoba Oil stearyl citrate
Jojoba Oil palmityl citrate
Jojoba Oil chloro h I
Jojoba Oil Propyl gallate
Jojoba Oil P ro allol
Jojoba Oil Alpha naphthol
Jojoba Oil Ascorbic acid
Jojoba Oil Natural tocopherols
Jojoba Oil Citric acid
Jojoba Oil Sage extract
Jojoba Oil Rosemary
Jojoba Oil eugenol
Hemp Oil 3,4,5-trih drox benzoic acid n- ro I ester
Hemp Oil 1,2,3-trih drox benzene
Hemp Oil Butylated H drox anisole
Hemp Oil t tert-but I-4-meth I henol
Hemp Oil 2,6-Di-tert-But I-1-H drox -4-Meth Ibenzene
Hemp Oil 6-ethox -1,2-dih dro-2,2,4-trimeth Iquinoline
Hemp Oil al ha-toco herol acetate
Hemp Oil alpha-tocopherol
Hemp Oil gamma-tocopherol
Hemp Oil delta-tocopherol
Hemp Oil dilauryl thiodi ro ionate
Hemp Oil isopropyl 2-h drox -4-methylthio butanoate
Hemp Oil dodecyl gallate
Hem Oil gallic acid
Hemp Oil octyl gallate

17


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TABLE B
Biodiesel Raw Material Antioxidants
Hemp Oil ascorbyl palmitate
Hemp Oil lecithin
Hemp Oil stearyl citrate
Hemp Oil palmityl citrate
Hemp Oil chloro h I
Hemp Oil Propyl gallate
Hemp Oil P ro allol
Hemp Oil Alpha naphthol
Hemp Oil Ascorbic acid
Hemp Oil Natural tocopherols
Hemp Oil Citric acid
Hemp Oil Sage extract
Hemp Oil Rosemary
Hemp Oil eugenol
Marine Oil 3,4,5-trih drox benzoic acid n- rop l ester
Marine Oil 1,2,3-trih drox benzene
Marine Oil Butylated H drox anisole
Marine Oil t-tert-but I-4-meth I henol
Marine Oil 2,6-Di-tert-Bu I-1-H drox -4-Meth Ibenzene
Marine Oil 6-ethox -1,2-dih dro-2,2,4-trimeth I uinoline
Marine Oil alpha-tocopherol acetate
Marine Oil alpha-tocopherol
Marine Oil gamma-tocopherol
Marine Oil delta-tocopherol
Marine Oil dilauryl thiodi ro ionate
Marine Oil iso ro I 2-h drox -4-meth Ithio butanoate
Marine Oil dodecyl gallate
Marine Oil gailic acid
Marine Oil octyl gallate
Marine Oil ascorbyl palmitate
Marine Oil lecithin
Marine Oil stearyl citrate
Marine Oil palmityl citrate
Marine Oil chloro h I
Marine Oil Propyl gallate
Marine Oil P ro allol
Marine Oil Alpha naphthol
Marine Oil Ascorbic acid
Marine Oil Natural tocopherols
Marine Oil Citric acid
Marine Oil Sage extract
Marine Oil Rosemary
Marine Oil eugenol
Poultry Fat 3,4,5-trih drox benzoic acid n- ro I ester
Poultry Fat 1,2,3-trih dro benzene

18


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TABLE B
Biodiesel Raw Material Antioxidants
Poultry Fat Butylated H drox anisole
Poultry Fat t-tert-but I-4-meth I phenol
Poultry Fat 2,6-Di-tert-But I-1-H drox -4-Meth Ibenzene
Poultry Fat 6-ethox -1,2-dih dro-2,2,4-trimeth I uinoline
Poultry Fat al ha-toco herol acetate
Poultry Fat al ha-toco herol
Poultry Fat gamma-tocopherol
Poultry Fat delta-tocopherol
Poultry Fat dilauryl thiodi ro ionate
Poultry Fat iso ro I 2-h drox -4-meth Ithio butanoate
Poultry Fat dodecyl allate
Poultry Fat allic acid
Poultry Fat octyl allate
Poultry Fat ascorbyl palmitate
Poultry Fat lecithin
Poultry Fat stearyl citrate
Poultry Fat palmityl citrate
Poultry Fat chloro h I
Poultry Fat Propyl gallate
Poultry Fat P ro allol
Poultry Fat Alpha naphthol
Poultry Fat Ascorbic acid
Poultry Fat Natural tocopherols
Poultry Fat Citric acid
Poultry Fat Sage extract
Poultry Fat Rosemary
Poultry Fat eugenol
Safflower Oil 3,4,5-trih drox benzoic acid n- ro I ester
Safflower Oil 1,2,3-trih drox benzene
Safflower Oil Butylated H drox anisole
Safflower Oil t-tert-but I-4-meth I henol
Safflower Oil 2,6-Di-tert-But I-1-H drox -4-Meth Ibenzene
Safflower Oil 6-ethox -1,2-dih dro-2,2,4-trimeth I uinoline
Safflower Oil al ha-toco herol acetate
Safflower Oil alpha-tocopherol
Safflower Oil gamma-tocopherol
Safflower Oil delta-tocopherol
Safflower Oil dilauryl thiodipropionate
Safflower Oil iso rop I 2-h drox -4-meth Ithio butanoate
Safflower Oil dodecyl gailate
Safflower Oil gallic acid
Safflower Oil octyl gallate
Safflower Oil ascorbyl aimitate
Safflower Oil lecithin
Safflower Oil stearyl citrate

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TABLE B
Biodiesel Raw Material Antioxidants
Safflower Oil palmityl citrate
Safflower Oil chloro h I
Safflower Oil Propyl gallate
Safflower Oil P ro allol
Safflower Oil Alpha naphthol
Safflower Oil Ascorbic acid
Safflower Oil Natural tocopherols
Safflower Oil Citric acid
Safflower Oil Sage extract
Safflower Oil Rosemary
Safflower Oil eugenol
Jatropha Oil 3,4,5-trih drox benzoic acid n- ro I ester
Jatropha Oil 1,2,3-trih drox benzene
Jatropha Oil Butylated H drox anisole
Jatropha Oil t-tert-but I-4-meth Iphenol
Jatropha Oil 2,6-Di-tert-But I-1-H drox -4-Meth Ibenzene
Jatropha Oil 6-ethox -1,2-dih dro-2,2,4-trimeth I uinoline
Jatropha Oil alpha-tocopherol acetate
Jatropha Oil al ha-tocopherol
Jatropha Oil gamma-tocopherol
Jatropha Oil delta-tocopherol
Jatropha Oil dilauryl thiodipropionate
Jatropha Oil isopropyl 2-h drox -4-meth Ithio butanoate
Jatropha Oil dodecyl gallate
Jatropha Oil allic acid
Jatropha Oil octyl gallate
Jatropha Oil ascorbyl aimitate
Jatropha Oil lecithin
Jatropha Oil stearyl citrate
Jatropha Oil aimit I citrate
Jatropha Oil chloro h I
Jatropha Oil Propyl allate
Jatropha Oil P ro allol
Jatropha Oil Alpha naphthol
Jatropha Oil Ascorbic acid
Jatropha Oil Natural tocopherols
Jatropha Oil Citric acid
Jatropha Oil Sage extract
Jatropha Oil Rosemary
Jatropha Oil eugenol
AI ae Oil 3,4,5-trih drox benzoic acid n-propyl ester
Algae Oil 1,2,3-trih droxybenzene
Algae Oil Butylated H drox anisole
Algae Oil t-tert but I-4-meth I henol
Algae Oil 2,6-Di-tert-But I-1-H drox -4-Meth Ibenzene


CA 02629613 2008-05-13
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TABLE B
Biodiesel Raw Material Antioxidants
Algae Oil 6-ethox -1,2-dih dro-2,2,4-trimeth I uinoline
AI ae Oil al ha-toco herol acetate
Algae Oil al ha-toco herol
Algae Oil gamma-tocopherol
Algae Oil delta-tocopherol
Algae Oil dilauryl thiodi ro ionate
Algae Oil isopropyl 2-h drox -4-meth Ithio butanoate
Algae Oil dodecyl gallate
Algae Oil gallic acid
Algae Oil octyl gallate
Algae Oil ascorbyl palmitate
Algae Oil lecithin
Algae Oil stearyl citrate
Algae Oil palmityl citrate
Algae Oil chloro h I
Algae Oil Propyl gallate
Algae Oil P ro allol
Algae Oil Alpha naphthol
Algae Oil Ascorbic acid
Algae Oil Natural tocopherols
Algae Oil Citric acid
Algae Oil Sage extract
Algae Oil Rosemary
Algae Oil eugenol

[0027] In one preferred embodiment, the fuel composition comprises a
biodiesel produced from soybean oil and 6-ethoxy-1,2-dihydro-2,2,4-
trimethylquinoline. In another preferred embodiment, the fuel composition
comprises
a biodiesel produced from soybean oil and 2-tert-butylhydroquinone. In yet
another
embodiment, the fuel composition comprises a biodiesel produced from yellow
grease (80% vegetable oil and 20% inedible tallow) and 6-ethoxy-1,2-dihydro-
2,2,4-
trimethylquinoline. In a further embodiment, the fuel composition comprises a
biodiesel produced from fish oil and 6-ethoxy-1,2-dihydro-2,2,4-
trimethylquinoline.
Those skilled in the art will appreciate that the concentration of
antioxidants added to
the biodiesel will vary depending on the source of biodiesel. In one
embodiment,
the fuel composition comprises a biodiesel produced from soybean oil and from
about 20 ppm to about 2000 ppm of 6-ethoxy-1,2-dihydro-2,2,4-
trimethylquinoline.
In another embodiment, the fuel composition comprises a biodiesel produced
from
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soybean oil and from about 50 ppm to about 500 ppm of 6-ethoxy-1,2-dihydro-
2,2,4-
trimethylquinoline.
[0028] The present invention is also directed to a fuel composition
comprising a biodiesel and an antioxidant mixture comprising at least two
antioxidants and optionally, a polar solvent, a nonpolar solvent, and/or a
petroleum
based diesel. In one embodiment, the fuel composition comprises any of the
biodiesels as described in Part I and an antioxidant mixture comprising at
least two
antioxidant as described in Part II of the specification above. In another
embodiment, the fuel composition comprises a first antioxidant having Formula
(I), a
second antioxidant not having Formula (I), a polar solvent, and a nonpolar
solvent,
as described in Part II of the specification above, wherein the two solvents
form a
homogeneous liquid. Preferably, the nonpolar solvent is a biodiesel as
described in
Part I of the specification above. Of course those skilled in the art will
appreciate
that the antioxidant mixtures will vary considerably depending on the type of
biodiesel to be stabilized. Exemplary fuel compositions are presented in Table
C
below.

TABLE C
Biodiesel Raw Material Antioxidants and/or Solvent s
Soybean Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Soybean Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene
Soybean Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hyd roxy-4-M ethyl be nzen e and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Soybean Oil 2-tert-but Ih droquinone and citric acid
Soybean Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hyd roxy-4-M ethyl be nzen e and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline and 2-tert-but Ih droquinone
Soybean Oil 2-tert-b utyl hydroq u i none and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline and corn oil
Soybean Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene and vegetable oil
Soybean Oil 6-ethoxy-l,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Soybean Oil 6-ethoxy- 1,2-d i hyd ro-2,2,4-tri m ethyl q ui nol i ne, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated h drox anisole, and propylene glycol

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TABLE C
Biodiesel Raw Material Antioxidants and/or Solvent s
Soybean Oil 6-ethoxy-1,2-dihydro-2,2,4-trimefihylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
palmitate, and propylene glycol
Soybean Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Soybean Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih dro uinone, lecithin, and corn oil
Yellow Grease 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Yellow Grease Butylated Hydroxyanisole and 2,6-Di-tert Butyl-l-
H drox -4-Meth Ibenzene
Yellow Grease Butylated Hydroxyanisole and 2,6-Di-tert Butyl-1-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Yellow Grease 2-tert-but Ih droquinone and citric acid
Yellow Grease Butylated Hydroxyanisole and 2,6-Di-tert Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Yellow Grease 2-tert-b utyl hyd roq ui none and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Yellow Grease Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene and vegetable oil
Yellow Grease 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Yellow Grease 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated hydroxyanisole, and propylene glycol
Yellow Grease 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
paimitate, and propylene glycol
Yellow Grease 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih droquinone, stearyl citrate, and corn oil
Yellow Grease 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih droquinone, lecithin, and corn oil
Corn Oil 2-tert-butyl hydroqui none and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Corn Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1 -
H drox -4-Meth Ibenzene
Corn Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hyd roxy-4-M ethyl be nzen e and 6-ethoxy-1,2-dihydro-
2,2,4-trimethylquinoline

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TABLE C
Biodiesel Raw Material Antioxidants and/or Solvent s
Corn Oil 2-tert-but Ih dro uinone and citric acid
Corn Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Corn Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Corn Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene and vegetable oil
Corn Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Corn Oil 6-ethoxy- 1,2-d i hyd ro-2,2,4-trim ethyl q u i nol i ne, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated h drox anisole, and propylene glycol
Corn Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
palmitate, and propylene glycol
Corn Oil 6-ethoxy-1,2-dihydro-2,2,4-firimefihylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Corn Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih droquinone, lecithin, and corn oil
Rapeseed Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Rapeseed Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene
Rapeseed Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Rapeseed Oil 2-tert-but Ih dro uinone and citric acid
Rapeseed Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Rapeseed Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Rapeseed Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
H drox -4-Meth Ibenzene and vegetable oil
Rapeseed Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Rapeseed Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated hydroxyanisole, and propylene glycol

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TABLE C
Biodiesel Raw Material Antioxidants and/or Solvenfi s
Rapeseed Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
paimitate, and propylene I col '
Rapeseed Oil 6-ethoxy- 1,2-di hyd ro-2,2,4-trim ethyl q u i nol i ne, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Rapeseed Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih dro uinone, lecithin, and corn oil
Coconut Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Coconut Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
H drox -4-Meth Ibenzene
Coconut Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Coconut Oil 2-tert-but Ih droquinone and citric acid
Coconut Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Coconut Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline and corn oil
Coconut Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1 -
Hdrox -4-Meth Ibenzene and vegetable oil
Coconut Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Coconut Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated hydroxyanisole, and propylene glycol
Coconut Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
palmitate, and propylene glycol
Coconut Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih droquinone, stearyl citrate, and corn oil
Coconut Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih droquinone, lecithin, and corn oil
Peanut Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Peanut Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
H drox -4-Meth Ibenzene
Peanut Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimethylquinoline



CA 02629613 2008-05-13
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TABLE C
Biodiesel Raw Material Antioxidants and/or Solvent s
Peanut Oil 2-tert-but Ih dro uinone and citric acid
Peanut Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but hydrog o uinone
Peanut Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Peanut Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene and vegetable oil
Peanut Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Peanut Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated h drox anisole, and propylene glycol
Peanut Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
palmitate, and propylene I col
Peanut Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Peanut Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih dro uinone, lecithin, and corn oil
Palm Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Palm Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
H drox -4-Meth Ibenzene
Palm Oil Butylated Hydroxyanisole and 2,6-Di-tert Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Palm Oil 2-tert-but Ih dro uinone and citric acid
Palm Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline and 2-tert-but Ih droquinone
Palm Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Palm Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
H drox -4-Meth Ibenzene and vegetable oil
Palm Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Palm Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated hydroxyanisole, and propylene glycol

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TABLE C
Biodiesel Raw Material Antioxidants and/or Solvent s
Palm Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
palmitate, and propylene glycol
Palm Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Palm Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl paimitate, propyl gallate,
2-tert-but Ih dro uinone, lecithin, and corn oil
Fish Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Fish Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene
Fish Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Fish Oil 2-tert-bu Ih droquinone and citric acid
Fish Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Fish Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Fish Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene and vegetable oil
Fish Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Fish Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl paimitate,
butylated h drox anisole, and propylene glycol
Fish Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
palmitate, and propylene glycol
Fish Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Fish Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih dro uinone, lecithin, and corn oil
Tallow 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Tallow Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1 -
H Hyd r-4-Meth Ibenzene
Tallow Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimethylquinoline

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TABLE C
Biodiesel Raw Material Antioxidants and/or Solvent s
Tallow 2-tert-butylhydrog uinone and citric acid
Tallow Butylated Hydroxyanisole and 2,6-Di-tert Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Tallow 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Tallow Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene and vegetable oil
Tallow 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Tallow 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated h drox anisole, and propylene glycol
Tallow 6-ethoxy-1,2-dihydro-2,2,4-trirnethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
palmitate, and propylene glycol
Tallow 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Tallow 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih droquinone, lecithin, and corn oil
Lard 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Lard Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene
Lard Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Lard 2-tert-but Ih dro uinone and citric acid
Lard Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Lard 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Lard Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
H drox -4-Meth Ibenzene and vegetable oil
Lard 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Lard 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated hydroxyanisole, and propylene glycol

28


CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
TABLE C
Bi:odiesel Raw Material Antioxidants and/or Solvent s
Lard 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
palmitate, and propylene glycol
Lard 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Lard 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih dro uinone, lecithin, and corn oil
Cottonseed Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Cottonseed Oil Butylated Hydroxyanisole and 2,6-Di-tert Butyl-l-
H drox -4-Meth Ibenzene
Cottonseed Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Cottonseed Oil 2-tert-but Ih droquinone and citric acid
Cottonseed Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hyd roxy-4-M ethyl be nzen e and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Cottonseed Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Cottonseed Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene and vegetable oil
Cottonseed Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Cottonseed Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated h drox anisole, and propylene glycol
Cottonseed Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
palmitate, and propylene glycol
Cottonseed Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Cottonseed Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih droquinone, lecithin, and corn oil
Sunflower Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Sunflower Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene
Sunflower Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimethylquinoline

29


CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
TABLE C
Biodiesel Raw Material Antioxidants and/or Solvent s
Sunflower Oil 2-tert-but hydrog o uinone and citric acid
Sunflower Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hyd roxy-4-M ethyl be nzen e and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Sunflower Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Sunflower Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene and vegetable oil
Sunflower Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Sunflower Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl paimitate,
butylated h drox anisole, and proeylene glycol
Sunflower Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
palmitate, and propylene glycol
Sunflower Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Sunflower Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih dro uinone, lecithin, and corn oil
Camelina Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Camelina Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene
Camelina Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Camelina Oil 2-tert-but Ih dro uinone and citric acid
Camelina Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Camelina Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Camelina Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene and vegetable oil
Camelina Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
but lated hydroxyanisole, and propylene glycol



CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
TABLE C
Biodiesel Raw Material Antioxidants and/or Solvent s
6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
palmitate, and propylene glycol
6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih dro uinone, lecithin, and corn oil
Jojoba Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Jojoba Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene
Jojoba Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Jojoba Oil 2-tert-bu Ih droquinone and citric acid
Jojoba Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hyd roxy-4-M ethyl be nzen e and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Jojoba Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline and corn oil
Jojoba Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
H drox -4-Meth Ibenzene and vegetable oil
Jojoba Oil 6-ethoxy-l,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Jojoba Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated h drox anisole, and propylene glycol
Jojoba Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
paimitate, and propylene glycol
Jojoba Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Jojoba Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih dro uinone, lecithin, and corn oil
Hemp Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Hemp Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
H drox -4-Meth Ibenzene
Hemp Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimethylquinoline

31


CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
TABLE C
Biodiesel Raw Material Antioxidants and/or Solvent s
Hemp Oil 2-tert-but Ih dro uinone and citric acid
Hemp Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Hemp Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Hemp Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene and vegetable oil
Hemp Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Hemp Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated h drox anisole, and propylene glycol
Hemp Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
palmitate, and propylene glycol
Hemp Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Hemp Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih dro uinone, lecithin, and corn oil
Frying Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Frying Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
H drox -4-Meth Ibenzene
Frying Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
F in Oil 2-tert-but Ih dro uinone and citric acid
Frying Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih droquinone
Frying Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Frying Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene and vegetable oil
Frying Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Frying Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated h drox anisole, and propylene glycol

32


CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
TABLE C
Biodiesel Raw Material Antioxidants and/or Solvent s
Frying Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
paimitate, and propylene glycol
Frying Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Frying Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih dro uinone, lecithin, and corn oil
Marine Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Marine Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene
Marine Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Marine Oil 2-tert-but Ih droquinone and citric acid
Marine Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Marine Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Marine Oil Butylated Hydroxyanisole and 2,6-Di-tert Butyl-1-
H drox -4-Meth Ibenzene and vegetable oil
Marine Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Marine Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl paimitate,
butylated h drox anisole, and propylene glycol
Marine Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
aimitate, and propylene glycol
Marine Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Marine Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih dro uinone, lecithin, and corn oil
Poultry Fat 2-tert-butyl hyd roqui none and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Poultry Fat Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
H drox -4-Meth Ibenzene
Poultry Fat Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline

33


CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
TABLE C
Biodiesel Raw Material Antioxidants and/or Solvent s
Poultry Fat 2-tert-but Ih dro uinone and citric acid
Poultry Fat Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Poultry Fat 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Poultry Fat Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene and vegetable oil
Poultry Fat 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Poultry Fat 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated h drox anisole, and propylene glycol
Poultry Fat 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
palmitate, and propylene glycol
Poultry Fat 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Poultry Fat 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih dro uinone, lecithin, and corn oil
Safflower Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Safflower Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene
Safflower Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Safflower Oil 2-tert-but Ih dro uinone and citric acid
Safflower Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Safflower Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Safflower Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene and vegetable oil
Safflower Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Safflower Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated h drox anisole, and propylene glycol

34


CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
TABLE C
Biodiesel Raw Material Antioxidants and/or Solvent s
Safflower Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
palmitate, and propylene glycol
Safflower Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
SafFlowerOil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih dro uinone, lecithin, and corn oil
Jatropha Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Jatropha Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene
Jatropha Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hyd roxy-4- M ethyl benzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline
Jatropha Oil 2-tert-but Ih droquinone and citric acid
Jatropha Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Jatropha Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth Iquinoline and corn oil
Jatropha Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene and vegetable oil
Jatropha Oil 6-ethoxy- 1,2-d i hydro-2,2,4-tri m ethyl q ui nol i ne and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Jatropha Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl paimitate,
butylated h drox anisole, and propylene glycol
Jatropha Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
paimitate, and propylene glycol
Jatropha Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Jatropha Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih yd lecithin, and corn oil
Algae Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline
Algae Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene
Algae Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-1-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimethylquinoline



CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
TABLE C
Biodiesel Raw Material Antioxidants and/or Solvent s
Algae Oil 2-tert-but hydrog o uinone and citric acid
Algae Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-Methylbenzene and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and 2-tert-but Ih dro uinone
Algae Oil 2-tert-butylhydroquinone and 6-ethoxy-1,2-dihydro-
2,2,4-trimeth I uinoline and corn oil
Algae Oil Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
H drox -4-Meth Ibenzene and vegetable oil
Algae Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and 2-
tert-butylhydroquinone, 1,2-Propanediol, citric acid,
and corn oil
Algae Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, propyl
gallate, dilauryl thiodipropionate, ascorbyl palmitate,
butylated h drox anisole, and propylene glycol
Algae Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, dodecyl
gallate, alpha naphthol, natural tocopherol, ascorbyl
palmitate, and propylene glycol
Algae Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-6-di-
tert-butyl-4-methylphenol, pyrogallol, 2-tert-
but Ih dro uinone, stearyl citrate, and corn oil
Algae Oil 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, natural
mixed tocopherols, ascorbyl palmitate, propyl gallate,
2-tert-but Ih dro uinone, lecithin, and corn oil

[0029] In a preferred embodiment, the fuel composition comprises a
biodiesel produced from soybean oil and an antioxidant mixture comprising 2-
tert-
butylhydroquinone (TBHQ), 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline (EQ),
and
vegetable oil. In another embodiment, the fuel composition comprises a
biodiesel
produced from soybean oil and an antioxidant mixture comprising Butylated
Hydroxyanisole (BHA), 2,6-Di-tert-Butyl-l-Hydroxy-4-Methylbenzene (BHT), and
vegetable oil. Such an antioxidant mixture is sold under the trademark
PETGUARD
and PETGUARD 4 (PG4) and may be purchased commercially from Novus
International, Inc. In yet another embodiment, the fuel composition comprises
a
biodiesel produced from soybean oil and an antioxidant mixture comprising 2-
tert-
butylhydroquinone (TBHQ), citric acid, and vegetable oil. Such an antioxidant
mixture is sold under the trademark FEEDGUARD and may be purchased
commercially from Novus International, Inc.
[0030] In yet another embodiment, the fuel composition comprises a
biodiesel produced from soybean oil and an antioxidant mixture comprising 2-
tert-
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butylhydroquinone and 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline and corn
oil.
Such an antioxidant mixture is sold under the trademark SANTOQUIN Q and may
be purchased commercially from Novus International, Inc. In a further
embodiment,
the fuel composition comprises a biodiesel produced from soybean oil and an
antioxidant mixture comprising 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline,
2-tert-
butyl hydroqui none, 1,2-Propanediol, citric acid, and corn oil. Such an
antioxidant
mixture is sold under the trademark AGRADO R and may be purchased
commercially from Novus International, Inc. In yet another embodiment, the
fuel
composition comprises a biodiesel produced from soybean oil and an antioxidant
mixture comprising butylated hydroxyanisole, 2,6-Di-tert-Butyl-l-Hydroxy-4-
Methylbenzene, 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 2-tert-
butylhydroquinone.
[0031] In one embodiment, the fuel composition comprises a biodiesel
produced from yellow grease and an antioxidant mixture comprising 6-ethoxy-1,2-

dihydro-2,2,4-trimethylquinoline, 2-tert-butylhydroquinone, 1,2-Propanediol,
citric
acid, and corn oil. In one embodiment, the fuel composition comprises a
biodiesel
produced from fish oil and an antioxidant mixture comprising 6-ethoxy-1,2-
dihydro-
2,2,4-trimethylquinoline, 2-tert-butylhydroquinone, 1,2-Propanediol, citric
acid, and
corn oil.
[0032] In one embodiment, the fuel composition comprises a first
antioxidant having Formula (I), preferably 6-ethoxy-1,2-dihydro-2,2,4-
trimethylquinoline, a second antioxidant not having Formula (I), a polar
solvent, and
a nonpolar solvent, preferably a biodiesel produced from soybean oil. In
another
embodiment, the fuel composition comprises a biodiesel produced from soybean
oil,
a first antioxidant, preferably 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline,
a second
antioxidant, preferably a mixture of propyl gallate, dilauryl
thiodipropionate, ascorbyl
paimitate, and butylated hydroxyanisole, and a polar solvent, preferably
propylene
glycol. In yet another embodiment, the fuel composition comprises a biodiesel
produced from soybean oil, a first antioxidant, preferably 6-ethoxy-1,2-
dihydro-2,2,4-
trimethylquinoline, a second antioxidant, preferably a mixture of dodecyl
gallate,
alpha naphthol, natural tocopherol, and ascorbyl palmitate, and a polar
solvent,
preferably propylene glycol. In a further embodiment, the fuel composition
comprises a biodiesel produced from soybean oil, a first antioxidant,
preferably 6-

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ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, a second antioxidant, preferably
a
mixture of 2-6-di-tert-butyl-4-methylphenol, pyrogallol, 2-tert-
butylhydroquinone, and
stearyl citrate, and a second nonpolar solvent, preferably corn oil. In
another
embodiment, the fuel composition comprises a biodiesel produced from soybean
oil,
a first antioxidant, preferably 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline,
a second
antioxidant, preferably a mixture of natural mixed tocopherols, ascorbyl
palmitate,
propyl gallate, 2-tert-butylhydroquinone, and lecithin, and a second nonpolar
solvent,
preferably corn oil. In yet another embodiment, the fuel composition comprises
a
biodiesel produced from soybean oil, a first antioxidant, preferably 6-ethoxy-
1,2-
dihydro-2,2,4-trimethylquinoline, a second antioxidant, preferably a mixture
of citric
acid, 2-tert-butylhydroquinone, and 1,2-Propanediol, and a second nonpolar
solvent,
preferably corn oil.
[0033] Those skilled in the art will appreciate that the concentration of
antioxidants added to the biodiesel will vary depending on the source of
biodiesel.
In one embodiment, the fuel composition comprises a biodiesel produced from
soybean oil and an antioxidant mixture comprising from about 20 ppm to about
500
ppm of 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, from about 20 ppm to
about
500 ppm of a mixture of Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-
Hydroxy-4-
Methylbenzene, and from about 10 to about 60 ppm of 2-tert-butylhydroquinone.
In
another embodiment, the fuel composition comprises a biodiesel produced from
soybean oil and an antioxidant mixture comprising about 400 ppm of 6-ethoxy-
1,2-
dihydro-2,2,4-trimethylquinoline, about 40 ppm of a mixture of Butylated
Hydroxyanisole and 2,6-Di-tert-Butyl-l- Hyd roxy-4- M ethyl benzene, and about
50 ppm
of 2-tert-butylhydroquinone. In yet another embodiment, the fuel composition
comprises a biodiesel produced from soybean oil and an antioxidant mixture
comprising about 40 ppm of 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline,
about 40
ppm of a mixture of Butylated Hydroxyanisole and 2,6-Di-tert-Butyl-l-Hydroxy-4-

Methylbenzene, and about 50 ppm of 2-tert-butylhydroquinone.
[0034] In addition, the concentration of antioxidants will also vary in
accordance with the oxidative stability desired for the fuel. There are
various
methods generally known in the art to measure the oxidative stability of a
fuel,
including the Rancimat Method, the Oxidative Stability Index (OSI) Method,
Active
Oxygen Method (AOM), the Standard Test Method for Oxidation Stability of
Distillate

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Fuel oil (ASTM D-2274), both of which are detailed in the examples. These
methods
may be utilized by a skilled artisan to formulate blends of antioxidants
having a
suitable concentration of each ingredient in order for the antioxidant blend
to impart
the desired oxidative stability for the fuel of the invention. For example,
all oils and
fats have a resistance to oxidation, which depends on the degree of
saturation,
natural or added antioxidants, prooxidants or prior abuse. Oxidation is slow
until this
resistance is overcome, at which point oxidation accelerates and becomes very
rapid. The length of time before this rapid acceleration of oxidation is the
measure of
the resistance to oxidation and is commonly referred to as the induction
period. The
OSI Method measures this induction period. Another method used in the art to
measure induction period is the Rancimat Method. The fuel compositions of the
present invention, as shown in Example 2, typically have an induction time
greater
than 6 hours.
[0035] The AOM Method measures the time (in hours) required for a
sample of fat or oil to attain a predetermined value under the specific
conditions of
the test. The length of this period of time is assumed to be an index of
resistance to
rancidity. The fuel compositions of the present invention, as shown in Example
1,
generally have a peroxide value of from about 4 meq/kg fat to about 400 meq/kg
fat
after 20 hours under the AOM Method.
[0036] The ASTM Method (D-2274) measures the insolubles of fuels under
specified oxidizing conditions at 95 C. In particular, the method calculates
the total
insoluble mass (mg/100 mL) as the sum of the filterable insolubles and the
adherent
insolubles. The calculations are further described in the examples. In one
example,
a fuel composition comprising a biodiesel produced from yellow grease and 6-
ethoxy-1,2-dihydro-2,2,4-trimethylquinoline has a total insoluble mass of 0.9
mg/mL,
as shown in Example 3.
[0037] In one embodiment, a fuel composition of the invention comprises a
biodiesel and a petroleum based diesel wherein the fuel composition has
improved
oxidative stability. In another embodiment, the fuel composition comprises any
of
the composition of Table A and a petroleum based diesel fuel wherein the fuel
composition has improved oxidative stability. In yet another embodiment, the
fuel
composition comprises any of the compositions of Table C and a petroleum based
diesel fuel.

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[0038] In one embodiment, the method of increasing the oxidative stability
of a fuel composition comprises contacting a biodiesel with an antioxidant
mixture
that increases the oxidative stability of the fuel.
[0039] It is generally known that the addition of biodiesel to diesel fuel
increases nitrogen oxide (NOX) emissions. Wyatt, et al. Fuel Properties and
Nitrogen
Oxide Emission Levels of Biodiesel Produced from Animal Fats, Journal of the
American Oil Chemists' Society, Vol. 82, No. 8, pg 585-591 (2005). The
addition of
antioxidants to the biodiesel fuel of the invention or a fuel comprising a
biodiesel and
petroleum based diesel of the invention, however, has lowered the NOX
emissions of
the fuels as compared to a B20 fuel without the addition of at least one
antioxidant or
to a petroleum based diesel fuel. In one embodiment, a fuel composition of the
invention comprises a biodiesel source other than rapeseed oil, frying oil,
sunflower
oil, and beef tallow and at least one antioxidant selected from the group
consisting of
1,2,3-trihydroxybenzene, alpha-tocopherol acetate, gamma-tocopherol, delta-
tocopherol, dilauryl thiodipropinate, isopropyl 2-hydroxy-4-methylthio
butanoate,
dodecyl gallate, gallic acid, octyl gallate, lecithin, stearyl citrate,
palmityl citrate,
chlorophyl, and 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline wherein the fuel
composition has a lower NOX emission than a B20 fuel without the addition of
at least
one antioxidant. In another embodiment, a fuel composition of the invention
comprises a biodiesel source other than rapeseed oil, frying oil, sunflower
oil, and
beef tallow and at least one antioxidant selected from the group consisting of
1,2,3-
trihydroxybenzene, alpha-tocopherol acetate, gamma-tocopherol, delta-
tocopherol,
dilauryl thiodipropinate, isopropyl 2-hydroxy-4-methylthio butanoate, dodecyl
gallate,
gallic acid, octyl gallate, lecithin, stearyl citrate, palmityl citrate,
chlorophyl, and 6-
ethoxy-1,2-dihydro-2,2,4-trimethylquinoline wherein the fuel composition has a
lower
NOx emission than a petroleum based diesel fuel.
[0040] In one embodiment, a fuel composition of the invention comprises
any of the compositions of Table 2 and a petroleum based diesel wherein the
fuel
composition has a lower NOX emission than a B20 fuel without the addition of
at least
one antioxidant. In another embodiment, the fuel composition comprises any of
the
compositions of Table 2 and a petroleum based diesel wherein the fuel
composition
has a lower NO,e emission than a petroleum based diesel fuel. In a further
embodiment, the fuel composition has a reduction of NOR emissions of at least
about



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1% as compared to B20 fuel without the addition of at least one antioxidant.
In yet
another embodiment, the fuel composition has a reduction of NOx emissions of
at
least about 2%, 4%, 6%, 8%, 10% as compared to B20 fuel without the addition
of at
least one antioxidant.
[0041] In one embodiment, the method of reducing the NOX emissions of a
fuel composition comprises contacting a biodiesel with an antioxidant mixture
that
decreases the NO,e emissions of the fuel.
[0042] Those skilled in the art will appreciate that the properties of the
biodiesel fuel compositions of the invention will also vary considerably
depending the
combination of fuel and antioxidant used. The physical and chemical properties
that
are generally measured for a biodiesel composition include kinematic viscosity
at
40 C, acid value, density, cold filter plugging point, and sulphated ash. The
ASTM
Standard for the kinematic viscosity of a 100% biodiesel composition at 40 C
(D-
445) is between 1.9 and 6.0 mm2/sec. The biodiesel fuel compositions of the
invention have a kinematic viscosity at 40 C of less than about 5.0 mm2/sec,
less
than about 4.5 mm2/sec, and less than about 4.0 mm2/sec. The ASTM Standard for
the acid value of a 100% biodiesel composition (D-664) is 0.8 mg KOH/g. The
biodiesel fuel compositions of the invention have an acid value of less than
about
0.75 mg KOH/g, less than about 0.6 mg KOH/g, less than about 0.5 mg KOH/g,
less
than about 0.45 mg KOH/g, less than about 0.3 mg KOH/g, less than about 0.2 mg
KOH/g, less than about 0.1 mg KOH/g. The biodiesel fuel compositions of the
invention have a density at 20 C of less than 0.884 g/cm3, less than about
0.88
g/cm3, less than about 0.87 g/cm3, less than about 0.865 g/cm3. The biodiesel
compositions of the invention have a cold filter plugging point (CFPP) of at
least -1
C, at least -2 C, at least -5 C, at least -10 C. The ASTM standard for the
maximum percent by mass of sulphated ash of a 100% biodiesel composition (D-
874) is 0.002 % by mass. The biodiesel compositions of the invention have a
sulphated ash percent by mass of less than about 0.002% by mass, less than
about
0.001 % by mass.

IV. Additional Agents
[0043] The biodiesel fuel compositions of the invention may contain
additional agents that enhance one or more characteristics of the fuel. Those
skilled
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in the art will appreciate that the selection of the particular agent will
vary
considerably depending on the type of fuel used. In particular, these
additives may
be particularly beneficial when the fuel composition comprises a biodiesel and
a
petroleum based diesel. Suitable additives, for example, may include, but are
not
limited to, cetane improvers and/or ignition accelerator agent, corrosion
inhibitors
and/or metal deactivators, cold flow improvers, and the like, as described
below.
[0044] Preferred organic nitrates are substituted or unsubstituted alkyl or
cycloalkyl nitrates having up to about 10 carbon atoms, preferably from 2 to
10
carbon atoms. The alkyl group may be either linear or branched. Specific
examples
of nitrate compounds suitable for use in preferred embodiments include, but
are not
limited to the following: methyl nitrate, ethyl nitrate, n-propyl nitrate,
isopropyl nitrate,
allyl nitrate, n-butyl nitrate, isobutyl nitrate, sec-butyl nitrate, tert-
butyl nitrate, n-amyl
nitrate, isoamyl nitrate, 2-amyl nitrate, 3-amyl nitrate, tert-amyl nitrate, n-
hexyl
nitrate, 2-ethylhexyl nitrate, n-heptyl nitrate, sec-heptyl nitrate, n-octyl
nitrate, sec-
octyl nitrate, n-nonyl nitrate, n-decyl nitrate, n-dodecyl nitrate,
cyclopentylnitrate,
cyclobexyl nitrate, methylcyclohexyl nitrate, isopropylcyclohexyl nitrate, and
the
esters of alkoxy substituted aliphatic alcohols, such as I-methoxypropyl-2-
nitrate, 1-
ethoxpropyl-2 nitrate, 1-isopropoxy-butyl nitrate, 1-ethoxylbutyl nitrate and
the like.
Preferred alkyl nitrates are ethyl nitrate, propyl nitrate, amyl nitrates, and
hexyl
nitrates. Other preferred alkyl nitrates are mixtures of primary amyl nitrates
or
primary hexyl nitrates. By primary is meant that the nitrate functional group
is
attached to a carbon atom that is attached to two hydrogen atoms. Examples of
primary hexyl nitrates include n-hexyl nitrate, 2-ethylhexyl nitrate, 4-methyl-
n-pentyl
nitrate, and the like. Preparation of the nitrate esters may be accomplished
by any of
the commonly used methods: such as, for example, esterification of the
appropriate
alcohol, or reaction of a suitable alkyl halide with silver nitrate. Another
additive
suitable for use in improving cetane and/or reducing particulate emissions is
di-t-
butyl peroxide.
[0045] Conventional ignition accelerators may also be used, such as
hydrogen peroxide, benzoyl peroxide, di-tert-butyl peroxide, and the like.
Moreover,
certain inorganic and organic chlorides and bromides, such as, for example,
aluminum chloride, ethyl chloride or bromide may find use in the preferred

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embodiments as primers when used in combination with the other ignition
accelerators.
[0046] The low temperature operability of diesel fuel is commonly
characterized by the cloud point, and the cold filter plugging point (CFPP) or
the low
temperature filterability test (LTFT). Thermal Stabilizers may also be added
to the
biodiesel composition. In one embodiment, the composition may also contain
jojoba
oil as an additional component. It is a liquid that has antioxidant
characteristics and
is capable of withstanding very high temperatures without losing its
antioxidant
abilities. Jojoba oil is a liquid wax ester mixture extracted from ground or
crushed
seeds from shrubs native to Arizona, California and northern Mexico. The
source of
jojoba oil is the Simmondsia chinensis shrub, commonly called the jojoba
plant. It is
a woody evergreen shrub with thick, leathery, bluish-green leaves and dark
brown,
nutlike fruit. Jojoba oil may be extracted from the fruit by conventional
pressing or
solvent extraction methods. The oil is clear and golden in color. Jojoba oil
is
composed almost completely of wax esters of monounsaturated, straight-chain
acids
and alcohols with high molecular weights (C16-C26). Jojoba oil is typically
defined as
a liquid wax ester with the generic formula RCOOR", wherein RCOOH represents
oleic acid (C18), eicosanoic acid (C20) and/or erucic acid (C22), and wherein -
-R"OH
represents eicosenyl alcohol (C20), docosenyl alcohol (C22) and/or tetrasenyl
alcohol (C24) moieties. Pure esters or mixed esters having the formula RCOOR",
wherein R is a C20-C22 alk(en)yI group and wherein R" is a C20-C22 alk(en)yl
group, may be suitable substitutes, in part or in whole, for jojoba oil. Acids
and
alcohols including monounsaturated straight-chain alkenyl groups are most
preferred.
[0047] Other oils that are known for their thermal stability include peanut
oil, cottonseed oil, rape seed (canola) oil, macadamia oil, avocado oil, palm
oil, palm
kernel oil, castor oil, all other vegetable and nut oils, all animal oils
including mammal
oils (e.g., whale oils) and fish oils, and combinations thereof. In one
embodiment, the
oil may be alkoxylated, for example, methoxylated or ethoxylated. Alkoxylation
is
preferably conducted on medium chain oils, such as castor oil, macadamia nut
oil,
cottonseed oil, and the like. Alkoxylation may offer benefits in that it may
permit
coupling of oil/water mixtures in a fuel, resulting in a potential reduction
in nitrogen
oxides and/or particulate matter emissions upon combustion of the fuel.

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[0048] Other suitable thermal stabilizers known in the art include liquid
mixtures of alkyl phenols, including 2-tert-butylphenol, 2,6-di-tert-
butylphenol, 2-tert-
butyl-4-n-butylphenol, 2,4,6-tri-tert-butylphenol, and 2,6-di-tert-butyl-4-n-
butylphenol
which are suited for use as stabilizers for middle distillate fuels (U.S. Pat.
No.
5,076,814 and U.S. Pat. No. 5,024,775 to Hanlon, et al.). Other commercially
available hindered phenolic antioxidants that also exhibit a thermal stability
effect
include 2,6-di-t-butyl-4-methylphenol; 2,6-di-t-butylphenol; 2,2'-methylene-
bis(6-t-
butyl-4-methylphenol); n-octadecyl 3-(3,5-di-t-butyl-4-hydroxyphenyl)
propionate;
1,1,3-tris(3-t-butyl-6-methyl-4hydroxyphenyl) butane; pentaerythrityl
tetrakis[3-(3,5-
di-t-butyl-4-hydroxyphenyl) propionate]; di-n-octadecyl(3,5-di-t-butyl-4-
hydroxybenzyl)phosphonate; 2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)
mesitylene;
and tris(3,5-di-t-butyl-4-hydroxybenzyl)isocyanurate (U.S. Pat. Nos.
4,007,157, U.S.
Pat. No. 3,920,661). Other suitable thermal stabilizers include:
pentaerythritol co-
esters derived from pentaerythritol, (3-alkyl-4-hydroxyphenyl)-alkanoic acids
and
alkylthioalkanoic acids or lower alkyl esters of such acids which are useful
as
stabilizers of organic material normally susceptible to oxidative and/or
thermal
deterioration. (U.S. Pat. No. 4,806,675 and U.S. Pat. No. 4,734,519 to Dunski,
et al.);
hindered phenyl phosphites (U.S. Pat. No. 4,207,229 to Spivack); hydrocarbyl
thioalkylene phosphites (U.S. Pat. No. 3,524,909); hydroxybenzyl thioalkylene
phosphites (U.S. Pat. No. 3,655,833); and the like.
[0049] Certain compounds suitable for use are capable of performing as
both antioxidants and as thermal stabilizers. Therefore, in certain
embodiments it
may be preferred to prepare formulations containing as additional components a
hydrophobic plant oil extract in combination with a single compound that
provides
both a thermal stability and antioxidant effect, rather than two different
compounds,
one providing thermal stability and the other antioxidant activity. Examples
of
compounds known in the art as providing some degree of both oxidation
resistance
and thermal stability include diphenylamines, dinaphthylamines, and
phenyinaphthylamines, either substituted or unsubstituted, e.g., N,N'-
diphenylphenylenediamine, p-octyldiphenylamine, p,p-dioctyldiphenylamine, N-
phenyl-l-naphthylamine, N-phenyl-2-naphthylamine, N-(p-dodecyl)phenyl-2-
naphthylamine, di-1 -naphthylamine, and di-2naphthylamine; phenothazines such
as
N-alkylphenothiazines; imino(bisbenzyl); and hindered phenols such as 6-(t-

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butyl)phenol, 2,6-di-(t-butyl)phenol, 4-methyl-2,6-di-(t-butyl) phenol, 4,4'-
methylenebis(-2,6-di-(t-butyl)phenol), and the like.
[0050] Certain lubricating fluid base stocks are known in the art to exhibit
high thermal stability and as such, may be beneficial in certain embodiments
of the
invention. Such base stocks may be capable of imparting thermal stability to
the
formulations of preferred embodiments, and as such may be substituted, in part
or in
whole, for jojoba oil. Suitable base stocks include polyalphaolefins, dibasic
acid
esters, polyol esters, alkylated aromatics, polyalkylene glycols, and
phosphate
esters.
[0051] A variety of polyalphaolefins may be utilized in the fuel composition
of the invention. Polyalphaolefins are hydrocarbon polymers that contain no
sulfur,
phosphorus, or metals. Polyalphaolefins have good thermal stability, but are
typically
used in conjunction with a suitable antioxidant. Dibasic acid esters also
exhibit good
thermal stability, but are usually also used in combination with additives for
resistance to hydrolysis and oxidation.
[0052] Several polyol esters may be used in the fuel composition of the
invention. Polyol esters include molecules containing two or more alcohol
moieties,
such as trimethylolpropane, neopentylglycol, and pentaerythritol esters.
Synthetic
polyol esters are the reaction product of a fatty acid derived from either
animal or
plant sources and a synthetic polyol. Polyol esters have excellent thermal
stability
and may resist hydrolysis and oxidation better than other base stocks.
Naturally
occurring triglycerides or vegetable oils are in the same chemical family as
polyol
esters. However, polyol esters tend to be more resistant to oxidation than
such oils.
The oxidation instabilities normally associated with vegetable oils are
generally due
to a high content of linoleic and linolenic fatty acids. Moreover, the degree
of
unsaturation (or double bonds) in the fatty acids in vegetable oils correlates
with
sensitivity to oxidation, with a greater number of double bonds resulting in a
material
more sensitive to and prone to rapid oxidation.
[0053] Several trimethylolpropane esters are suitable for use in the fuel
compositions of the invention. Trimethylolpropane esters may include mono, di,
and
tri esters. Neopentyl glycol esters may include mono and di esters.
Pentaerythritol
esters include mono, di, tri, and tetra esters. Dipentaerythritol esters may
include up
to six ester moieties. Preferred esters are typically of those of long chain
monobasic



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fatty acids. Esters of C20 or higher acids are preferred, e.g., gondoic acid,
eicosadienoic acid, eicosatrienoic acid, eicosatetraenoic acid,
elcosapentanoic acid,
arachidic acid, arachidonic acid, behenic acid, erucic acid, docosapentanoic
acid,
docosahexanoic acid, or ligniceric acid. However in certain embodiments,
esters of
C18 or lower acids may be preferred, e.g., butyric acid, caproic acid,
caprylic acid,
capric acid, lauric acid, myristoleic acid, myristic acid, pentadecanoic acid,
palmitic
acid, palmitoleic acid, hexadecadienoic acid, hexadecatienoic acid,
hexadecatetraenoic acid, margaric acid, margroleic acid, stearic acid,
linoleic acid,
octadecatetraenoic acid, vaccenic acid, or linolenic acid. In certain
embodiments, it
may be preferred to esterify the pentaerythritol with a mixture of different
acids.
[0054] In certain embodiments, an alkylated aromatic may be utilized in the
fuel compositions of the invention. Alkylated aromatics are formed by the
reaction of
olefins or alkyl halides with aromatic compounds, such as benzene. Thermal
stability
is similar to that of polyalphaolefins, and additives are typically used to
provide
oxidative stability. Polyalkylene glycols are polymers of alkylene oxides
exhibiting
good thermal stability, but are typically used in combination with additives
to provide
oxidation resistance. Phosphate esters are synthesized from phosphorus
oxychloride
and alcohols or phenols and also exhibit good thermal stability.
[0055] In certain embodiments, it may be preferred to prepare formulations
containing jojoba oil in combination with other vegetable oils. For example,
it has
been reported that crude meadowfoam oil resists oxidative destruction nearly
18
times longer than the most common vegetable oil, namely, soybean oil.
Meadowfoam oil may be added in small amounts to other oils, such as triolein
oil,
jojoba oil, and castor oil, to improve their oxidative stability. Crude
meadowfoam oil
stability could not be attributed to common antioxidants. One possible
explanation for
the oxidative stability of meadowfoam oil may be its unusual fatty acid
composition.
The main fatty acid from meadowfoam oil is 5-eicosenoic acid, which was found
to
be nearly 5 times more stable to oxidation than the most common fatty acid,
oleic
acid, and 16 times more stable than other monounsaturated fatty acids. See
"Oxidative Stability Index of Vegetable Oils in Binary Mixtures with
Meadowfoam Oil,"
Terry, et al., United States Department of Agriculture, Agricultural Research
Service,
1997.

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[0056] Any of a number of different types of suitable detergent additives
can be included in diesel fuel compositions of various embodiments. These
detergents include succinimide detergent/dispersants, long-chain aliphatic
polyamines, and long-chain Mannich bases. Use of fuel-soluble long chain
aliphatic
polyamines as induction cleanliness additives in distillate fuels is
described, for
example, in U.S. Pat. No. 3,438,757. Use of fuel-soluble Mannich base
additives
formed from a long chain alkyl phenol, formaldehyde (or a formaldehyde
precursor
thereof), and a polyamine to control induction system deposit formation in
internal
combustion engines is described, for example, in U.S. Pat. No. 4,231,759. The
detergent additives, for example, are effective in reducing carburetor
deposits and
fuel injector deposits.
[0057] The diesel fuel compositions of various embodiments
advantageously may contain one or more antiwear agents. Preferred antiwear
agents include long chain primary amines incorporating an alkyl or alkenyl
radical
having 8 to 50 carbon atoms. The amine to be employed may be a single amine or
may consist of mixtures of such amines. Examples of long chain primary amines
-which can be used in the preferred embodiments are 2-ethylhexyl amine, n-
octyl
amine, n-decyl amine, dodecyl amine, oleyl amine, linolylamine, stearyl amine,
eicosyl amine, triacontyl amine, pentacontyl amine and the like. A
particularly
effective amine is oleyl amine obtainable from Akzo Nobel Surface Chemistry
LLC of
Chicago, Ill. under the name ARMEEN 0 or ARMEEN OD. Other suitable amines
which are generally mixtures of aliphatic amines include ARMEEN T and
ARMEEN TD, the distilled form of ARMEEN T which contains a mixture of 0-2%
of
tetradecyl amine, 24% to 30% of hexadecyl amine, 25% to 28% of octadecyl amine
and 45% to 46% of octadecenyl amine. ARMEEN T and ARMEEN TD are derived
from tallow fatty acids. Lauryl amine is also suitable, as is ARMEEN 12D
obtainable
from the supplier indicated above. This product is about 0-2% of decylamine,
90% to
95% dodecylamine, 0-3% of tetradecylamine and 0-1 % of octadecenylamine.
Amines of the types indicated to be useful are well known in the art and may
be
prepared from fatty acids by converting the acid or mixture of acids to its
ammonium
soap, converting the soap to the corresponding amide by means of heat, further
converting the amide to the corresponding nitrile and hydrogenating the
nitrile to
produce the amine. In addition to the various amines described, the mixture of

47


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amines derived from soya fatty acids also falls within the class of amines
above
described and is suitable for use according to this invention. It is noted
that all of the
amines described above as being useful are straight chain, aliphatic primary
amines.
Those amines having 16 to 18 carbon atoms per molecule and being saturated or
unsaturated are particularly preferred. Other preferred antiwear agents
include
dimerized unsaturated fatty acids, preferably dimers of a comparatively long
chain
fatty acid, for example one containing from 8 to 30 carbon atoms, and may be
pure,
or substantially pure, dimers. Alternatively, and preferably, the material
sold
commercially and known as "dimer acid" may be used. This latter material is
prepared by dimerizing unsaturated fatty acid and consists of a mixture of
monomer,
dimer and trimer of the acid. A particularly preferred dimer acid is the dimer
of
linoleic acid.
[0058] The fuel composition may include a variety of demulsifiers.
Demulsifiers are molecules that aid the separation of oil from water usually
at very
low concentrations. They prevent formation of a water and oil mixture. A wide
variety of demulsifiers are available for use in the fuel formulations of
various
embodiments, including, for example, organic sulfonates, polyoxyalkylene
glycols,
oxyalkylated phenolic resins, and like materials. Particularly preferred are
mixtures of
alkylaryl sulfonates, polyoxyalkylene glycols and oxyalkylated alkylphenolic
resins,
such as are available commercially from Baker Petrolite Corporation of Sugar
Land,
Tex. as TOLADO. Other known demulsifiers can also be used.
[0059] A variety of corrosion inhibitors are available for use in the fuel
formulations of various embodiments. Use can be made of dimer and trimer
acids,
such as are produced from tall oil fatty acids, oleic acid, linoleic acid, or
the like.
Products of this type are currently available from various commercial sources,
such
as, for example, the dimer and trimer acids sold under the EMPOL by Cognis
Corporation of Cincinnati, Ohio. Other useful types of corrosion inhibitors
are the
alkenyl succinic acid and alkenyl succinic anhydride corrosion inhibitors such
as, for
example, tetrapropenylsuccinic acid, tetrapropenylsuccinic anhydride,
tetradecenylsuccinic acid, tetradecenylsuccinic anhydride, hexadecenylsuccinic
acid,
hexadecenylsuccinic anhydride, and the like. Also useful are the half esters
of
alkenyl succinic acids having 8 to 24 carbon atoms in the alkenyl group with
alcohols
such as the polyglycols.

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[0060] If desired, the fuel compositions may contain a conventional type of
metal deactivator of the type having the ability to form complexes with heavy
metals
such as copper and the like. Typically, the metal deactivators used are
gasoline
soluble N,N'-disalicylidene-l,2-alkanediamines or N,N'-disalicylidene-l,2-
cycloalkanediamines, or combinations thereof. Examples include N,N'-
disalicylidene-
1,2-ethanediamine, N,N'-disalicylidene-l,2-propanediamine, N,N'-disalicylidene-
1,2-
cyclo-hex- anediamine, and N,N"-disalicylidene-N'-methyl-dipropylene-triamine.
[0061] The various additives that can be included in the diesel
compositions of this invention are used in conventional amounts. The amounts
used
in any particular case are sufficient to provide the desired functional
property to the
diesel composition, and such amounts are well known to those skilled in the
art.
DEFINITIONS
[0062] To facilitate understanding of the invention, a number of terms and
abbreviations as used herein are defined below:
[0063] The term "AGRADO " refers to a form of ethoxyquin.
[0064] The term "AGRADO R " refers to a form of ethoxyquin and TBHQ.
[0065] The term "Acid Number" refers to the milligrams of KOH required in
tests to neutralize all the acidic constituents present in a 1 gram sample of
fuel
product. This property is often used to indicate the extent of contamination
or
oxidation of fuels.
[0066] The term "AOM" stands for the Active Oxygen Method. The method
measures the time (in hours) required for a sample of fat or oil to attain a
predetermined value under the specific conditions of the test.
[0067] The term "B20" refers to a fuel composition having about 20% by
weight biodiesel and about 80% by weight petroleum based diesel.
[0068] The term "Cloud Point" refers to the temperature at which small
solid crystals are first visually observed as the fuel is cooled. This is the
most
conservative measurement of cold flow properties.
[0069] The term "Cold Filter Plugging Point (CFPP) (or LTFT)" refers to the
temperature at which a fuel will cause a fuel filter to plug due to fuel
components,
which have begun to crystallize or gel.

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[0070] The term "FEEDGUARD 20 " refers to an antioxidant mixture of
TBHQ, citric acid, and vegetable oil.
[0071] The term "Induction time" stands one the measure of the resistance
to oxidation.
[0072] The term "Kinematic viscosity at 40 C" refers to the measure of a
fuel's resistance to flow under gravity at a specific temperature, in this
case 40 C.
[0073] The term "Oxidative Stability" refers to the ability to slow down the
oxidation of a fuel.
[0074] The term "OSI" stands for the Oil Stability Index. The method
measures the induction time of a fuel.
[0075] The term "PETGUARD " refers to an antioxidant mixture of BHA,
BHT, and vegetable oil.
[0076] The term "PETGUARD 4 " refers to an antioxidant mixture of BHA,
BHT, and vegetable oil.
[0077] The term "PV" stands for peroxide value.
[0078] The term "PPM" stands for parts per million.
[0079] The term "SANTOQUIN " refers to a form of ethoxyquin.
[0080] The term "SANTOQUIN Q " refers to a form of ethoxyquin and
TBHQ.
[0081] The term "TENOX 21 " refers to an antioxidant mixture of TBHQ,
glyceryl oleate, propylene glycol, vegetable oil, and citric acid.
[0082] The term "yellow grease" as used herein refers to waste grease
from restaurants and low-grade fats from rendering plants; yellow grease is a
mixture
of vegetable oils and animal fats.

EXAMPLES
[0083] The following examples illustrate various embodiments of the
invention.

Example 1: Effectiveness of Various Antioxidants to Stabilize Biodiesel
[0084] The stability of biodiesel alone or in the presence of various
antioxidants was tested using two methods approved by the American Oil
Chemists
Society, i.e., the Active Oxygen Method (AOM) (AOCS Official Method Cd 12-57)


CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
and the Oxidation Stability Index (OSI) method (AOCS Official Method Cd 12b-
92)
which is equivalent to the Rancimat method. The biodiesel comprised soybean
oil,
yellow grease, or menhaden oil. Unless completely liquefied, each sample was
melted at a temperature not more than 10 C above its melting point. The
antioxidants included SANTOQUINO, SANTOQUIN QO, AGRADOO, AGRADO RO,
PETGUARDT " and PETGUARD 4T"'. The levels of the antioxidants tested are
presented in Table 1. All of the conditions were tested in duplicate.
[0085] AOM measures the levels of peroxides, or oxidation products, in a
lipid sample after exposure to air and heat. For this, 20 ml of sample (
antioxidant)
was added to the reaction tubes. The aeration tubing assembly was inserted
into the
reaction tube and adjusted such that the end of the air delivery tubing was 5
cm
below the surface of the sample. The tube and the sample were placed in a
container of vigorously boiling water for 5 min. The tube was then removed
from the
water, wiped dry, and transferred immediately to the constant temperature
heater
maintained at 97.8 0.2 C. The aeration tubing was connected to the
capillary on
the manifold, and air was bubbled into the sample to accelerate oxidation.
After 20
hr, the sample was analyzed for peroxide content. The lower the peroxide or
AOM
value (expressed in meq/kg of lipid) the more stable the lipid sample. For
animal-
derived lipids, an AOM value of 20 meq/kg or greater indicates rancidity.
[0086] During the OSI method, a stream of air is passed through a lipid
sample and the effluent air from the lipid sample is bubbled through a test
vessel
containing deionized water, whose conductivity is continuously monitored. As
the oil
oxidizes, volatile organic acids are generated and become trapped in the
water,
thereby increasing its conductivity. To perform OSI, conductivity tubes were
filled
with 50 ml of deionized water and probes were attached. The conductivity of
the
water in the tubes was verified to be constant with a reading of 25 pS/cm or
less.
Twenty ml of (liquefied) sample ( antioxidant) was placed directly into the
bottom of
the reaction tube. Assays performed with biodiesel soybean oil or yellow
grease
were conducted at 110 C, and assays performed with fish (menhanden) oil were
performed at 80 C. The tubing from the air manifold was connected to the
conductivity measurement tube, and the aeration tubing was adjusted so that it
was
within 5 mm of the bottom of both the reaction and the conductivity tubes. The
airflow was adjusted to 2.5 0.2 ml/sec. A computer was used to monitor the

51


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WO 2007/062304 PCT/US2006/060920
conductivity of each probe in the instrument and a plot of water conductivity
vs. time
obtained from the reader was generated. The OSI value is defined as the
induction
period in hours and mathematically represents the inflection point (second
derivative)
of the plot that reflects the maximum change in the oxidation rate. The higher
the
OSI value, the more stable the oil. The EU standard for stabilization is a
value of 6
(hr) or greater.
[0087] The AOM and OSI values for the different antioxidants are
presented in Table 1. These tests revealed that SANTOQUINO Q, AGRADO RO,
and TBHQ were effective at reducing the oxidation of soybean oil, and that
AGRADO
RO was effective at reducing the oxidation of yellow grease or menhanden oil.

Table 1. Effectiveness of Various Antioxidants to Stabilize Biodiesel
Type of Antioxidant Level AOM value OSI value
Biodiesel me /k (hr)
Soybean oil none 197 6
Soybean oil SANTOQUINO 500 ppm 186 6
Soybean oil SANTOQUINO Q 200 ppm 57 10
Soybean oil SANTOQUINO Q 400 ppm 4 12
Soybean oil SANTOQUINO Q 1000 ppm 6 17
Soybean oil AGRADO RO 500 ppm 4 12
Soybean oil AGRADO RO 800 ppm 7 14
Soybean oil PETGUARDT"" 500 ppm 6 7
Soybean oil PETGUARD 4T"" 500 ppm 4 7
Soybean oil TBHQ 200 ppm 2 23
Yellow grease none 350 4
Yellow grease AGRADO 500 ppm 317 4
Yellow grease AGRADO RO 500 ppm 4 10
Menhaden oil none - 2
Menhaden oil SANTOQUINO 400 ppm - 7
Menhaden oil AGRADO RO 400 ppm - 11
Menhaden oil AGRADO RO 1000 ppm - 22
Example 2: Effectiveness of Antioxidant Mixtures to Stabilize Soybean
Biodiesel
[0088] The ability of various antioxidants or combinations of antioxidants to
stabilize biodiesel comprising soybean oil were compared using the AOM and OSI
methods, essentially as described in Example 1. The antioxidants included
ethoxyquin (EQ), FeedGuard 20 (FG20), PETGUARD 4TM (PG4), TBHQ, and BHT.
Each of the antioxidants or antioxidant combination was used at a
concentration of

52


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500 ppm. Table 2 presents the various conditions, as well as the AOM and OSI
values. TBHQ was the best antioxidant in preventing the oxidation of soybean
oil, as
assayed by both methods.

Table 2. Antioxidant Effectiveness to Prevent Oxidation
Type of Antioxidant(s) at 500 ppm AOM value OSI value
Biodiesel me /k hr
Soybean oil none 278 5.2
Soybean oil EQ 322 4.4
Soybean oil EQ (30%) + TBHQ (10%) 377 6.3
Soybean oil PG4 (20% BHA & 20% BHT) 110 6.4
Soybean oil PG4 (15% BHA &15% BHT) + EQ 155 6.4
(25%)
Soybean oil FG20 (20% TBHQ & 10% citric acid) 152 6.1
Soybean oil BHT 87 7.9
Soybean oil TBHQ 11 12.6
Example 3: Ability of Antioxidant Mixtures to Stabilize Soybean Biodiesel
[0089] The effectiveness of various formulations of ethoxyquin (EQ),
PETGUARD 4T"" (PG4), and TBHQ to stabilize a biodiesel comprised of soybean
oil
were compared using the AOM and OSI methods, as detailed in Example 1. Table 3
presents the concentration of each component of the formulations, and the AOM
and
OSI values. This experiment revealed that any formulation comprising TBHQ at
50
ppm had excellent antioxidant activity.

Table 3. Effectiveness of Antioxidant Formulations
Type of EQ PG4 TBHQ AOM value OSI value
Biodiesel (ppm) m (ppm) me /k (hr)
Soybean oil none none none 245 6
Soybean oil 40 40 10 94 8
Soybean oil 400 40 10 98 8
Soybean oil 40 400 10 74 9
Soybean oil 400 400 10 73 8
Soybean oil 40 40 50 6 11
Soybean oil 400 40 50 5 11
So bean oil 40 400 50 6 12
Soybean oil 400 400 50 5 12
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CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
Example 4: Effectiveness of Antioxidant Blends (#1) to Stabilize Biodiesel
[0090] Additional combinations of antioxidants were compared for their
effectiveness to inhibit oxidation of a biodiesel comprising soybean oil. The
stability
of the biodiesel alone or in the presence of an antioxidant formulation was
tested
using the AOM and OSI methods, as detailed in Example 1. The antioxidants
(AOX)
tested were ethoxyquin (EQ), BHT, pyrogallol (PY), TBHQ, and stearyl citrate
(SC).
The nonpolar solvent was corn oil (CO). The level of each antioxidant in the
formulations is presented in Table 4. The application rate of each formulation
was
2000 ppm. Table 4 also presents the AOM and OSI values. It was found that
formulations comprising 500 ppm of ethoxyquin (25%) and 200 ppm of pyrogallol
(10%) were particularly effective in stabilizing the biodiesel (shaded in
Table 4).
Table 4. Effectiveness of Various Antioxidant Formulations
Blend EQ BHT PY TBH SC Total Corn AOM os-
(ppm) (ppm) (ppm) (ppm) (ppm) AOX oil value value
(ppm) (ppm) me /k (hr)
Control 374 0.1
1-1 10 10 10 10 100 140 1860 372 1.0
1-2 500 10 10 10 10 540 1460 375 1.7
1-3 10 250 10 10 10 290 1710 400 2.1
1-4 500 250 10 10 100 870 1130 400 3.2
1-5 10 10 200 10 10 240 1760 75 6.3
.. ~'~.. ~
................:..............................................................
.....................:~...............,....................
..... .... ......:......
1-7 10 250 200 10 100 570 1430 74 6.7
:.>:.::.::.; .: .::: ..:::::::: :. ~::: ......: ...;;:.;:.; :.:::;::
..........::::. .:: .........: .::. ~::. ..~.:::::: ......,....::
.::.;:.::.::: ....:::: ... ::..............:::::: ::::: ...............
...........;...:: ..........................:.::.:.:
>:: I::< : <! :":
f'~.:. :t::<=?''>:>:<'>:::::::''
::::::::
1-9 10 10 10 250 10 290 1710 309 4.0
1-10 500 10 10 250 100 870 1130 123 6.2
1-11 10 250 10 250 100 620 1380 375 5.2
1-12 500 250 10 250 10 1020 980 46 6.9
1-13 10 10 200 250 100 570 1430 56 9.1
:.:.::.:;; : . . . . . . . . . .: .: . . . . . . . . . . . . . . . . . . . . .
. . . .: : : : . . . . . . . . . . . .: : : : . . . . . . . . . . . . .: . . .
. . . . . . . . . . . . . . . . . . . . . . . . .: : :>:.;:.: :.::: :: . : :.:
:.;:. :.>:.:;:: . .: . . .: . ..: :.::.;: .;:.;:: .. . . :: . :. . ..;:.;:. :
>;:.::.>:.::.;. . . . . . . . . . . . . . . . . . .: . . . . . . . . . . . .
>;;:
...................... ...................... .....................
........................................... . .. 970.. ...
............. ::... :...:. :......:...
................................................. ..................
1-15 10 250 200 250 10 720 1280 55 9.3
_:.;:.>:.;. ..........::::.. ..
::...,~~.~Ã~ ........:...;:.;:.;:.:.::.::.;...:...:
: <::
1-17 10 10 10 10 10 50 1950 400 0
Example 5: Effectiveness of Antioxidant Blends (#2) to Stabilize Biodiesel
[0091] Additional combinations of antioxidants were compared for their
effectiveness to inhibit soybean oil biodiesel oxidation. The stability of the
biodiesel
alone or in the presence of an antioxidant formulation was tested using the
AOM and
OSI methods, as detailed in Example 1. The antioxidants tested were propyl
gallate
54


CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
(PG), ethoxyquin (EQ), dilauryl thiodipropionate (DD), ascorbyl paimitate
(AP), and
BHA. The polar solvent was propylene glycol (PGL). The level of each
antioxidant
in the formulations is presented in Table 5. The application rate of each
formulation
was 2000 ppm. As shown in Table 5, formulations comprising 300 ppm of propyl
gallate (15%) and 500 ppm of ethoxyquin (25%) were effective in preventing
biodiesel oxidation.

Table 5. Effectiveness of Various Antioxidant Formulations
Blend PG EQ DD AP BHA Total PGL AOM osi
(ppm) (ppm) (ppm) (ppm) (ppm) AOX (ppm) value vatue
(ppm) meq/k (hr)
Control 400 0.3
2-1 10 10 10 10 250 290 1710 212 6.0
2-2 300 10 10 10 10 340 1660 29 8.4
2-3 10 500 10 10 10 540 1460 36 7.6
: : : . . . . . . . .: . . . . . . .
:;:.;:.;:.;' ': : : .: . . . . .; . . : . . . . . :.: . . . . . . :.:
;;'<>:>5 .;::.;;:: : .;. . : : . .: : : : : . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . .: . :.;:.::.:.: . .: : . . . . . . . . .:
:><::::<::::::>:::::
...... '1.1... ....... .. 4:,"~.
. .................... ...................... .....................
............. ::::::<'~:~T........
....,............................................ ..................
....................... .......... .......... ............~}....
2-5 10 10 250 10 10 290 1710 400 2.8
2-6 300 10 250 10 250 820 1180 20 13.0
2-7 10 500 250 10 250 1020 980 61 7.5
;:; <.;:.;:: .: ,;; . . . . . . . .. : .: . . . . . . . : : : : : : . . . . .
. . . . : . . . . . . . . . . . .
..:::>:;<:::>::>::> >:::> : ~ :':::: ':::;>:
>:>:::::::::<'~ : :':;::::::::, :::::.,; :::<::~~ ~~::<: :: ::;:>
::::::<>:
::i:3:;::::::::::::~~<': >:~:~k::
i':::>::>:><'~;'::::::~~:::::>:::>>;::::::'1::i~::::<::......... ~.~. .
. .. : : :. ~~'. . . . . .......,. . . . . . . . . .~ . :. . . . ... . . . . .
. . :.. .. ~ ... . . .... .. ..: : : :. . . . . . ... ... . . . . . . .... .
.... . . . . . . . . . :. :. . .. ... ...... ...... .. .. :. ... ... . . .. .:
: . . . . . .: . . . . . . . . . . . . . . . . .. . . . . . . ... ..
......:,,.. , .... . . . . . . . . . . . . .
2-9 10 10 10 200 10 240 1760 355 2.9
2-10 300 10 10 200 250 770 1230 18 14.0
2-11 10 500 10 200 250 970 1030 24 9.5
?:::::ii'~:YY:: 1=0 i:::::::i'4: ~:~~i~ :::::::.'1.Q::::::: ::::::::::{: ::::
::i: :: :: ~:'.. :: :::::::: i~::(:i : ~ .. ' {~:::i::'i..:::::i:::: ~::i:~%~
: :::::i:?:i::i:::>: :ii::i .'=~==:::.:: ::;:~':
::..#~~0::::.
:.::.~:~:.:~
: ...................... .........~..: .... :.. . :..........I~ .....
...................... : ........... :. :...... .....................
............................................... :.. :.................
2-13 10 10 250 200 250 720 1280 79 6.5
2-14 300 10 250 200 10 770 1230 22 10.8
2-15 10 500 250 200 10 970 1030 5 8.8
,+..'~?::::::' :1li: :. ..~ ~:::i:::i: ::C::Ji':... :: ~~ ~: ~:ii::::::
:>'J::i~..: ~ :: ~ ::: ~i::::::i: ::::Si;;i= i.'..: ~~ ::: ?;.',:::::
:::i:::ifi ~::~ ~~:: .:{:i'i ::;;:::::::F .. ;. ~ <~::::::::::: :i:::ii: ~'r=;
~ :: ~:: ~:='::::: :::::'i}.::'~ :: . :: ~:j ::: ::::::'r::i~::~::ii~::
::i::'i::::i:::f::::: :::i"~~: i i'v .~ :::::::
.~.:::..::~:.5(~b
Example 6: Effectiveness of Antioxidant Blends (#3) to Stabilize Biodiesel
[0092] Additional combinations of antioxidants were compared for their
effectiveness to inhibit soybean oil biodiesel oxidation. The stability of the
biodiesel
alone or in the presence of an antioxidant formulation was tested using the
AOM and
OSI methods, as detailed in Example 1. The antioxidants tested were dodecyl
gallate (DG), ethoxyquin (EQ), alpha naphthol (AN), natural tocopherols (NT),
and
ascorbic acid (AA). The polar solvent was propylene glycol (PGL). The level of
each
antioxidant in the formulations is presented in Table 5. The application rate
of each
formulation was 2000 ppm. As shown in Table 6, formulations comprising 300 ppm



CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
of dodecyl gallate (15%) and 500 ppm of ethoxyquin (25%) prevented biodiesel
oxidation.

Table 6. Effectiveness of Various Antioxidant Formulations
Blend DG EQ AN NT AA Total PGL AOM osi
(ppm) (ppm) (ppm) (ppm) (ppm) AOX (ppm) value value
m me /k (hr)
Control 348 0.3
3-1 10 10 10 10 100 140 1860 380 0.4
3-2 300 10 10 10 10 340 1660 135 6.3
3-3 10 500 10 10 10 540 1460 380 5.1
::>::>::>::: : ~<: .: ...... ..::::: ....... :.::: .. .........: ...........
.................:::: .....::::: .........: .. ::>::>::><.....; .. ......
...................... ........::: .... ..... :::::::::::: ... ...........
...........;: .:::.
........................ ..................... .....................
..................... ..................... .....................
...................... .................... ............................
..................
3-5 10 10 200 10 10 240 1760 400 5.7
3-6 300 10 200 10 100 620 1380 36 9.2
3-7 10 500 200 10 100 820 1180 8 13.9
;::'::::: . '~ ''':::'';:::;: ':::::::::~3l;:/~;:::::::::
:::':%:;ti?\:d~%'>::' ':::::'::~ ' ~::: i:::: ';:::::::::::~::\ d?::;:::::;:;
;:;:;;:; ?: :~:; ::;:::: ::='::::~;~~~' ~:::'i:: ::'~::~ C7l G?":::':
:i::::i:::::::'=:::1:' ':::::: ::i:>": ::::::2:~: i:1:J2
:~::.... ~ :..........:. ............:......... ...:............ :::..
........ ~.......... ...:.......... :.::... ...... :~..........: ::........
~........ ... :................ ............ :~........... ..................
3-9 10 10 10 200 10 240 1760 377 3.4
3-10 300 10 10 200 100 620 1380 26 10.5
3-11 10 500 10 200 100 820 1180 252 6.2
....................... ..................... .....~............
..................... ..................... .....................
...................... .................... ............................
..................
3-13 10 10 200 200 100 520 1480 69 7.1
3-14 300 10 200 200 10 720 1280 37 12.0
3-15 10 500 200 200 10 920 1080 35 11.1
:: <: >:::>:>:<::.,:: :::t :.:.: >::>:::::>;<';' :> :: ::::::>:::::<:::> >::
::>::::::::::::::::> :: >::::::>::::::::
:.: > ; :;.::.:.:::.:::. : :;:.;;:
. : . . . .::::: :. . . .. .. . . ::::. .::::.: .: . . . .::::: .:::::::::.
.:: . ::.:
::::::.::: ~~:::.::..::::: ~~~.::::: ~~~.:... : :.::: ::::::..;:
Example 7: Effectiveness of Various Antioxidant Blends Applied at Different
Rates to Stabilize Biodiesel
[0093] The effectiveness of different concentrations of various antioxidant
blends to prevent biodiesel oxidation was compared using the AOM and OSI
methods, as described in Example 1. The antioxidants tested were ethoxyquin
(EQ),
natural mixed natural tocopherols (NMT), ascorbyl palmitate (AP), propyl
gallate
(PG), TBHQ, and lecithin (LE). The nonpolar solvent was corn oil. The level of
each antioxidant in the formulations is presented in Table 7. Each formulation
was
applied at either 200 ppm or 500 ppm. As shown in Table 7, the formulation
comprising EQ, NMT, AP, PG, and TBHQ at 500 ppm was most effective at
stabilizing biodiesel.

Table 7. Effectiveness of Different Application Rates of Various Antioxidant
Blends
Rate EQ NMT AP PG TBHQ LE CO AOM OSI
(ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) value value
(meq/kg) (hr)
56


CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
Control 400 0.8
200 100 0 0 0 200 0 1700 356 1.4
500 400 2.5
200 100 0 200 0 200 0 1500 352 1.8
500 400 4.1
200 100 0 200 200 200 0 1300 344 2.9
500 27 6.7
. . . . .................. ......... .......
:.:: '. ~: >:> ~:<:
200 . . ....... ......... ...,...., ....~. 40 3.
~fl.::: 0 5
::<;:;::::,;:::>:
::.:~~>:::::;<::> :'::>;:::::::::>: ~ ::'::::>:::::::::::::
::<:~ ...... ::.::... ....::: :............. .....................
.................... ............,......... ......................
..................... :..........,..:....... ::::.........:$..........
.......... ~......
200 100 0 200 0 200 200 1300 332 1.9
500 371 4.1
200 100 0 0 200 200 200 1300 400 2.7
500 37 5.9
200 100 300 200 200 200 200 800 325 3.5
500 20 8.5
Example 8: Effectiveness of Antioxidant Blends to Reduce Insolubles in
Biodiesel
[0094] The standard test method for oxidation stability of distillate fuel oil
(ASTM D2274; accelerated method) was also used to rate the effectiveness of
the
different antioxidant blends. This method measures the filterable insolubles,
the
adherent insolubles, and the total insolubles after an accelerated oxidative
process.
For this method, 400 ml of fuel was filtered through a cellulose ester
surfactant-free
membrane filter having a nominal pore size of 0.8 m. A clean oxygen delivery
tube
was placed in each clean oxidation test cell, and 350 ml of the filtered fuel
was
added to the test cell. The test cell was placed in a 95 C heating bath, and
oxygen
was bubbled through the test sample at a rate of 3 I/h for 16 hr. The test
sample was
allowed to cool to room temperature for no longer than four hours. The sample
was
then filtered through two filters simultaneously (Whatman GF/F filters). After
all the
fuel was pulled through the filters, three washes of 50 ml of isooctane were
used to
rinse the oxidation cell and the oxygen delivery tube. All rinses were passed
through
the filter assembly. Additionally, the rim of the filter media and the
adjacent parts of
the filter assembly were washed with another 50 ml of isooctane. The filtrate
was
discarded. The two filters were dried at 80 C for 30 min, and then cooled for
30 min.
Both filters were weighed. The upper filter is considered the sample filter,
while the
lower filter is considered the blank filter. The filterable insolubles mass
(A) in
milligrams per 100 ml was calculated. The mass of the blank (bottom) filter W,
was

57


CA 02629613 2008-05-13
WO 2007/062304 PCT/US2006/060920
subtracted from the weight of the sample (top) filter W2 and divided by 3.5 to
reduce
the result to a 100 ml basis (A =(W2-WI)/3.5).
[0095] After the oxidation cell and oxygen delivery tube were rinsed
(above), the adherent insolubles from the surfaces of those pieces were
dissolved
using three 75 ml rinses of trisolvent (equal parts of toluene, acetone, and
methanol).
If needed, a fourth 75 ml rinse of trisolvent was used. The trisolvent rinses
were
collected in pre-tared beakers, and evaporated. Two sets of weights were
recorded
- the tare weight and the after evaporation weight for the sample beaker, and
then a
tare and after evaporation weight for a blank beaker that contained only an
equivalent volume of trisolvent. The adherent insolubles mass (B) in
milligrams per
100 ml was also calculated. The tare mass of the blank (W3) and sample (W4)
beakers were subtracted from the final mass (after evaporation) of the blank
(W5)
and sample (W6) beakers. The difference between the blank and the sample was
then calculated, and divided by 3.5 to reduce the result to a 100 ml basis (B
= ((W6 -
W4) -(V1/5- W3))/3.5). The total insolubles mass (C) in milligrams per 100 ml
was
calculated as the sum of the filterable insolubles (A) and the adherent
insolubles (B),
such that C = A+ B.
[0096] A fuel composition comprising a biodiesel produced from yellow
grease was analyzed in the absence or presence of 2000 ppm SANTOQUIN using
the above method. It was found that the total insoluble mass decreased from
5.5
mg/100 MI to 0.9 mg/10 MI in the presence of the antioxidant.
[0097] Antioxidant blends were tested and the filterable insolubles,
adherent insolubles, and total insolubles were determined. The following
antioxidant
blends were tested: 1-6, 1-8, 1-14, and 1-16 from Example 4 (see Table 4); 2-4
and
2-12 from Example 5 (see Table 5); and 3-12 from Example 6 (see Table 6). Each
blend was tested at 500 ppm, 1000 ppm, and 2000 ppm. Controls included
biodiesel, and biodiesel containing 1000 ppm of TBHQ or 1000 ppm of TENOX-21
(TNX21). The results are presented in Table 8. All of the antioxidant blends,
with
the exception of the lowest concentration of blend 3-12, reduced the amount of
insolubles in the biodiesel.

Table 8. Reduction of Insolubles by Antioxidant Blends
Filterable Insolubles m /100m1
Control TBHQ TNX21 1-6 1-8 1-14 1-16 2-4 2-12 3-12
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0 3.8
500 0 0 0 0.1 0 0 2.8
1000 2.9 3.65 0 0.1 0.1 0 0.1 0.1
2000 0.4 0 0.3 0.1 0.2 0.1
Adherent Insolubles m /100 ml)
Control TBHQ TNX21 1-6 1-8 1-14 1-16 2-4 2-12 3-12
0 8.6
500 0.8 0.3 0.9 0.2 0.3 1.5 4
1000 0.1 2.85 0.3 0.1 1.3 0.1 0.2 0.4
2000 0.2 0.9 0.2 4.2 0.1 0.4
Total Insolubles m /100 ml)
Control TBHQ TNX21 1-6 1-8 1-14 1-16 2-4 2-12 3-12
0 12.4
500 0.8 0.3 0.9 0.3 0.3 1.5 6.8
1000 3 6.5 0 0.3 0.2 1.4 0.1 0.3 0.5
2000 0.6 0 0.9 0.5 4.3 0.3 0.5
59