Note: Descriptions are shown in the official language in which they were submitted.
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
FUEL COMPOSITIONS
This invention relates to a fuel composition, in particular a gasoline
composition
for transportation uses e.g. use in motor vehicles or aircraft.
For many years manufacturers of spark ignition combustion engines have been
striving for higher efficiency to make optimum use of hydrocarbon based fuels.
But such
engines require gasolines of higher octane number, which has been achieved in
particular
by addition of organo lead additives, and latterly with the advent of unleaded
gasolines,
by addition of MTBE. But combustion of any gasoline gives rise to emissions in
the
exhaust gases, e.g. of carbon dioxide, carbon monoxide, nitrogen oxides (NOx)
and toxic
hydrocarbons and such emissions are undesirable.
Unleaded gasolines have been discovered having high Octane Number but
producing low emissions on combustion.
The present invention provides an unleaded blend composition having a Motor
Octane Number (MON) of at least 81 or 85 and Research Octane Number (RON) of
at
least 91 or 94 which comprises component (a) a total of at least 10% or I S%
by volume
1 5 of the blend composition of at least one branched chain hydrocarbon, which
is an alkane
of 8-12 carbon atoms with at least 4 methyl or ethyl branches (hereinafter
called a
compound (A) there being a minimum of at least 1, 2, 5 or 10% by volume (of
the blend
composition), of at least one individual compound (A) and component (b) at
least one
liquid hydrocarbon or mixture thereof of bp60-160°C having a MON value
of at least 60
preferably at least 70 and RON value of at least 70 preferably at least 80 and
especially at
least 90, the total amount of component (b) being at least 20%, with the
preferred
proviso that the blend composition contains less than 5% of 223 trimethyl
pentane, and
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
especially less than I or 0.5%, and especially less than 0.5%, in total of 223
trimethyl
butane and 223 trimethyl pentane.
In another aspect the present invention provides an unleaded blend composition
of
MON value of at least 81 or 85 and RON value of at least 91 or 94 which
comprises
component (a) as defined above and as component (b) at least 20% in total of
one or
more refinery streams, such that the blend composition contains in total at
least 70% of
saturated hydrocarbons.
Unless otherwise stated all percentages in this specification are by volume,
and
disclosures of a number of ranges of amounts in the composition or gasoline
for 2 or
more ingredients includes disclosures of all sub-combinations of all the
ranges with all
the ingredients.
The compounds A are alkanes of 8-12 carbon atoms (especially 8 or 10 carbons)
with at least 4 methyl and/or ethyl branches, e.g. 4-6 branches, preferably 4
or 5 or
especially 4 branches. Methyl branches are preferred. The compounds usually
have their
longest chain of carbon atoms, hereinafter called their backbone chain, with 4-
7 e.g. 4-6
chain carbon atoms (especially 4 or 5) to which the methyl, and/or ethyl
branches are
attached. Advantageously, especially in relation to the first to tenth
groupings as
described further below, there are no branched groups constituting the
branches other
than methyl or ethyl, and, in the backbone chain of carbon atoms, there are
especially no
linear alkyl groups of more than 2 carbons nor 1,2 ethylene or 1,3 propylene
groups in
the chain, and especially no methylene groups in the chain except as part of
an ethyl
group; thus there are especially no n-propyl or n-butyl groups forming part of
the
backbone chain. Preferably there is at least one compound (A) alkane of 9-12
e.g. 9 or
10 carbons, and in this case there is usually less than SO% or 10% of an 8
carbon alkane
compound e.g. with 3 methyl branches.
The compounds can have 1 or 2 methyl or ethyl groups attached to the same
carbon atom of the backbone chain, especially 1 or 2 methyl groups and 0 or 1
ethyl
groups. The carbon atom in the backbone at which the branching occurs is non-
terminal
i.e. is an internal carbon in the backbone chain, especially the 2, 3 and/or 4
numbered
carbon in the backbone. Thus advantageously the compound has geminal methyl
substituents on position 2, 3 or 4 carbon atoms, especially position 2, but in
particular
position 3.
2
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
In a first grouping of compounds A, there is at least one pair of geminal
methyl
branch substituents, and they are on position 2, or there are 2 or 3 pairs of
geminal
branches at least 2 pairs being on vicinal (ie adjacent) carbon atoms, as in a
group -
CMe2-CMe2-.
In a second grouping of the compounds A there are 1, 2 or 3 pairs of geminal
methyl branch substituents on a 4-6 carbon chain backbone, and, if any Ethyl
CMe2-
structure is present, then there are 2 Ethyl CMe2 groups in the compound. The
compounds of the second grouping advantageously have a MON value of at least
100.
In a third grouping of the compounds, there is one geminal methyl branch
grouping
i.e. -CMe2- on the backbone, while on one or both of the adjacent carbon atoms
of the
backbone, there is/are one or two methyl or ethyl branches/especially 1 or 2
methyl
branches.
In a fourth grouping of the compounds there are one, two or three pairs of
geminal
methyl branches. If there are 2 or 3 pairs then at least 2 pairs are on
adjacent backbone
1 5 carbon atoms, and if there is only one pair, then they are preferably on
the 2 position
backbone carbon and there is a methyl branch at least on the 3 position
backbone carbon.
Such compounds usually have a RON value of at least 111. Advantageously the
compounds are of 8 or 10 carbon atoms.
In a fifth grouping the compound A has 2 or 3 pairs of geminal methyl branches
at
least 2 pairs being on adjacent backbone carbon atoms, and the compound has a
symmetrical structure. Such compounds usually have RON value of at least 120,
and
especially are of 8 or 10 carbon atoms.
In a sixth grouping the compounds have a linear backbone chain of 4 or 6
carbons
and have 4-6 e.g. 4, 5 or 6 especially 4 methyl branches, in at least one
geminal group
(CMez) especially in the absence of a 1,2 ethyl group in the backbone.
In a seventh grouping, the compounds have a linear backbone chain of 5 or 6
carbons and have 4-6 e.g. 4, 5 or 6 especially 4 branches in at least one
geminal group,
with the proviso that if there are 4 methyl branches and the compound contains
an Ethyl
CMe2 group, then the compound contains two such Ethyl CMeZ groups. Such
compounds are usually liquid at 25°C and generally have a RON value of
greater than
105. Especially there are only methyl branches; such compounds usually have a
MON
value of at least 101.
3
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
Advantageously in an eighth grouping the compounds A contain 1, 2 or 3 carbon
atoms with geminal methyl branches, and if there is only one such carbon atom
with
geminal branches, then there is/are one or two branches on a vicinal carbon
atom to the
geminal one, and any ethyl -C- chain group in the backbone chain has 5 carbon
atoms i.e.
is (Ethyl)ZCH or Ethyl CMe2-. Especially there are 2 or 3 vicinal carbon atoms
in the
backbone, each carrying 2 methyl branches.
A particularly preferred sub-class (ninth grouping) for the compound A is
alkanes
with alkyl substituents on vicinal internal carbon atoms, with a total of 4, S
or 6 carbon
atoms in said substituents.
Among this sub-class are preferred ones especially with geminal methyl groups
on
internal chain carbon atoms. Particularly preferred sub-class compounds A have
4 or 5
methyl substituents on the carbon backbone, especially with at least 2 on the
same
backbone carbon atom (in particular in two -CMe2- groups) especially in a -
CMez-CMe2
group.
In another aspect of the invention there is provided an unleaded blend
composition
having a MON value of at least 81 or 85 and RON value of at least 91 or 94,
which
comprises component (a) a total of at least 10 or 15% of one or more branched
alkane
compounds A' of 8-12 carbons (especially with 4-7 or 4-6 backbone carbon
atoms), with
at least 4 methyl or ethyl branches and with at least 2 backbone carbon atoms
which are
secondary and/or tertiary carbon atoms, with the proviso that if there are
only 2 such
carbon atoms, then both are tertiary, there being a minimum of at least 1, 2,
5 or 10%
(by volume of the composition) of at least one individual compound A', and
component
(b) of nature and in amount as described herein, with the preferred proviso as
described
above. In the above component A', which may be the same or different from A,
there
may thus in a tenth grouping be in the backbone internal (i.e. non-terminal)
carbon atoms
which are (i) 2 or 3 tertiary carbons, (ii) especially vicinal ones, or (iii)
2 tertiary and one
sec. carbon or (iv) 2 tertiary and one or 2 primary carbon, or (iv) 1 or 2
tertiary and 1 or
2 sec subject to at least 4 branches, in particular (vi) with the tert and a
sec. carbon
vicinal and (vii) when there are 2 tent, these are vicinal or non-vicinal and
(viii) with 1 or
2 vicinal tent and sec. carbons subject to at least 4 branches. The compounds
A' usually
are free from 2 primary internal backbone carbon atoms on vicinal carbons i.e.
as in 1,2
ethylene group. Preferably any primary internal backbone carbon atoms are not
between,
4
WO 01/21738 CA 02385720 2002-03-22 pCT/GB00/03569
e.g. adjacent on both sides to, a tert and/or sec, carbon on the one hand and
a tert and/or
sec. carbon on the other hand. Especially at least the said 2 backbone carbon
atoms
above in compounds A' are vicinal.
In another category, the eleventh grouping is of compounds AI which contain,
with the proviso of at least 4 branched groups, (i) as at least one end of the
backbone a
group of formula CHR'RZ where each of R' and RZ, which are the same or
different is a
methyl or ethyl group or (ii) as at least one end of the backbone a group of
formula
CR'RZR~ where R' and Rz are as defined above and R~ is methyl or ethyl.
Preferred are
such compounds A' which have both (i) and (ii), especially when the CHR'RZ
group is
CHMe2 when the compound has 8 carbons or a backbone of 5 carbons and when all
internal carbon atoms in the backbone chain are secondary or tertiary.
The compounds A or A' may have a boiling point at 1 bar pressure of 150-
175°C,
130-140°C, 110-129°C, or 90-109°C. In particular the
boiling point is preferably at least
105°C e.g. 105-175°C, with the preferred proviso that it is at
least 112°C such as 112-
1 5 175°C unless the compound A or A' has 4 alkyl branches.
In another category the compounds A or A' may have 4-6 methyl and/or ethyl
branches on a 4-7 or 4-6 carbon backbone, and especially a ratio of carbon
atom in
branches to carbon atoms in the backbone chain of at least 0.63:1 e.g. 0.63-
1.6:1 such as
0.63-1.0:1. The compounds usually have 9 or 10 carbons, unless the above ratio
is at
least 0.63, 0.75 or 0.9.
Preferred compounds are 3344 tetramethyl hexane (A1), 2233 tetramethyl butane
(A2), 2233 tetramethyl pentane (A7), 22334 pentamethyl pentane (A12) 22344
pentamethyl pentane (A13) 2334 tetramethyl pentane (A14) 2234 tetramethyl
pentane
(AIS) 223344 hexamethyl pentane (A16) 22446 pentamethyl heptane. Of these (AI)
and (A2) are most preferred with (A7) being also very valuable.
The compounds A and A' are either known compounds and may be made
according to the published literature, or are novel and may be made by
conventional
methods known per se in the literature (e.g. as described in Kirk Othmer
Encyclopaedia
of Chemical Technology 3rd Ed. Publ. Wiley). Examples of suitable methods of
preparation are known carbon-carbon coupling techniques for making alkanes.
The
technique may involve reactions of one or more usually 1 or 2 alkyl chlorides,
bromides
or iodides with an elemental metal of Group IA, IIA, IB or IIB of the Periodic
Table in
5
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
Advanced Inorganic Chemistry by F. A. Cotton + G.wilkinson, Pub. Interscience
New
York 2nd Ed. 1966, especially sodium, magnesium, or zinc. The alkyl halide is
usually a
branched chain one of 3-6 carbons, in particular with methyl or ethyl
branches, and
especially with the halogen atom attached to a CMe2 group in at least one of
the alkyl
halides. Preferably the halide is of formula MeCMeZX or EtCMe2X, where X is
CI, B or
I, and the other halide, if any, is a tertiary alkyl halide or a secondary one
e.g. of formula
RR'CHX, wherein at least one of R and R' is a branched alkyl group e.g. of 3-5
carbons
such as isopropyl or t-butyl, and the other (if any) is methyl or ethyl or a
primary
branched alkyl halide e.g. of formula R"CHZX, where R" is a branched alkyl
group 4-S
carbons with methyl or ethyl branches, such as isobutyl or isoamyl.
Alternatively both
halides can be secondary e.g. of formula RR'CHX, as defined above and
R"'R~'CHX
where R"' is methyl or ethyl and R'v is as defined for R, such as isopropyl or
one can be
secondary (as above) and one can be primary e.g. methyl or ethyl halide. The
methods of
coupling optimum for any particular compound A or A' depend on availability of
the
precursor alkyl halides) so that in addition to the above kinds, coupling via
methyl or
ethyl halides with branched alkyl halides of 6-9 carbons may also be used e.g.
pentamethyl ethyl bromide and methyl magnesium bromide to form A2. The alkyl
halides) can react together in the presence of the metal (as in a Wurtz
reaction with
sodium), or one can react first with the metal to form an organometallic
compound e.g. a
Grignard reagent or organo zinc, followed by reaction of the organometallic
with the
other alkyl halide. If desired the Grignard reagent reaction can be in the
presence of a
metal of Group IB or IIB, such as silver, zinc or copper (especially high
activity copper).
If desired the Grignard reagent from one or both alkyl halides can be reacted
with the
latter metal to form other alkyl metallic species e.g. alkyl silver or alkyl
copper
compounds, which can disproportionate to the coupled alkane. The Grignard
reagents)
can also react with a cuprous halide to form alkyl copper species for
disproportionation.
Finally an organometallic compound, wherein the metal is of Group IA or IIA
e.g. Li or
Mg can be coupled by reaction with a cuprous complex to give a coupled alkane.
Use of
only 1 alkyl halide gives a symmetrical alkane, while use of a mixture of
alkyl halides
gives a mixture of alkanes, usually each of the symmetrical dimers and an
unsymmetrical
alkane formed from both alkyl halides.
The above organometallic reactions are usually conducted under inert
conditions,
6
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
i.e. anhydrous and in the absence of oxygen e.g. under dry nitrogen. They are
usually
performed in an inert solvent e.g. a dry hydrocarbon or ether. At the end of
the reaction
any residual organometallic material is decomposed by addition of a compound
with
active hydrogen e.g. water or an alcohol, and the alkanes are distilled off,
either directly
or after distribution between an organic and aqueous phase.
Examples of the above processes are the coupling of tertbutyl chloride in the
presence of Mg and diethyl ether to form compound A(2) (as described by
D.T.Flood et
al, J.Amer Chem. Soc. 56, (1934) 1211, or R.E.Marker et al, J.Amer Chem. Soc.
60,
(1938) 2598 or F.C.Whiteman et al, J.Amer Chem. Soc. 55, (1933) 380), and the
corresponding coupling of EtCMe2 halides to form compound AI . Other
preparations of
highly branched alkanes are described in M Tamura and J.Kochi, J.Amer. Chem.
Soc.
Vo1.93, Part 6 (March 24, 1971) and F.O.Ginah et al, J. Org. Chem. Vol. 199,
55 pp584-
589 and R.Y.Levina & V.K.Daukshas, Zhur.Obschei Khim. Vol. 29 (1959) and
F L Howard etal, J Res. Nat. Bur. Standards Research Paper RP1779, Vol 38
March
1 5 1947 pp 365-395. The disclosures of these documents is incorporated herein
by
reference.
The crude alkanes made by the above processes, especially the symmetrical
ones,
may be used as such in the blends of the invention or may be purified further
e.g. by
distillation first. The crude unsymmetrical alkanes may be also purified, but
are
preferably used as such as the by-product alkanes are often useful
hydrocarbons for the
blend, e.g. coupling of t BuX and EtCMe2X as described above produces a
mixture of
alkanes containing A1, A2 and A7.
Other known methods of making the alkanes A or A', are reaction of alkyl
metallic
compounds e.g. Grignard reagents with carbonyl compounds such as aldehydes,
ketones,
esters, or anhydrides to form branched chain carbinols, which are dehydrated
to the
corresponding olefin, which is hydrogenated to the alkane. Thus 2,2,3,4-tetra
methyl
pentane may be made from isopropyl magnesium bromide and methyl t-butyl ketone
(followed by dehydration and hydrogenation),
Thus the present invention produces an unleaded blend composition of MON value
at least 81 or 85 and RON value at least 91 or 94 which comprises (a) a total
of at least
10 or 15% of one or more branched hydrocarbon compound A or Al there being a
minimum of at least l, 2 or 5% of at least one individual compound A or A' and
(b) at
7
WO 01/21738 CA 02385720 2002-03-22 pCT/GB00/03569
least 20% of at least one different liquid hydrocarbon of bp60-160°C
having a MON
value of at least 70 and RON value at least 90 especially when (b) is not
within the
definition of A or A'. Examples of the liquid hydrocarbons are paraffins, such
as linear
or branched chain alkanes of 4-8 carbons, such as isobutane, butane,
isopentane,
dimethyl alkanes such as 23 dimethyl butane, cycloalkanes, such as
cyclopentane and
cyclohexane, aromatics and olefins.
Another unleaded blend composition of the invention of MON value of at least
81
or 85 and RON value of at least 91 or 94 comprises component (a) as above and
component (b) at least 20% of at least one of a straight run naphtha, alkylate
isomerate
(bp25-80°C) heavy reformate, light reformate (bp20-79°C),
hydrocrackate, aviation
alkylate (bp30-190°C), straight run gasoline, cracked spirit, such as
heavy or light
catalytic cracked spirit or steam cracked spirit. The straight run products
are produced
directly from crude oil by atmospheric distillation. The naphtha may be light
naphtha of
bp30-90°C or medium naphtha of bp90-150°or heavy naphtha of by
150-220°C.
1 5 In the blends of the invention, the amount of at least one individual
compounds A
or A' is usually at least 1, 2 or 5%, or at least 10 or 15%, such as S-60%,
e.g. 1 S-60%,
or 8-25%, 20-35% or 30-55% or 2-10%. The amount of 2,2,4-trimethyl pentane if
present is usually at least 10% of the composition. Total amounts of trimethyl
pentanes
in the blend are preferable less than 69% of the blend, but advantageously at
least 26%
(especially when the amount of aromatics is less than 17%). If a 9 or 10
carbon alkane is
(a), then the amount of 2,2,4-trimethyl pentane is especially less than 70 or
50%. More
than one such compound A or A' may be present e.g. of higher and lower RON in
weight ratios of 9:1 to 0.5:99.5, such as 0.5:1 to 5:1 or 5:95 to 20:80,
particularly for
mixtures of compounds A1 and A2 and/or with higher or lower boiling points
(atmospheric pressure) e.g. those in which the compounds A and/or A' have
boiling
points differing by at least 10°C e.g. at least 40°C such as 10-
70°C or 20-50°C the
relative amounts being as described above. In the blends amounts of compounds
A or A'
of RON at least 138 e.g. AI may be 1-40%, such as 2-10 or 20-35%, while those
of
compounds A or A' of RON 120-138 e.g. A2 may be 1-60, such as 5-60, 8-25 or 30-
55% (especially when used with the higher RON compound) or 15-50% when used as
sole compound A. Total amounts of all compounds A and A' (if any) in the blend
are at
least 10 or I S% such as 15-70 e.g. 15-60, I S-40 or 30-55% or 40-60% or 10-
35%.
8
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
The blend may also comprise predominantly aliphatic refinery streams which are
usually liquid e.g. at 20°C such as naphtha, straight run gasoline
(also known as light
naphtha by 25-120°C), alkylate and isomerate. Amounts in total of these
may be 10-
70%, such as 10-30, 30-70 or 35-65%. Amounts of naphtha may be 0-70% or 1-70%
such as 10-30, 30-70 or 35-65%, while amounts of light naphtha may be 0 or 1-
70 such
as 1-20 or especially 30-65%, and amounts of medium naphtha may be 0 or 1-55,
such
as 3-20 or 15-55%. The volume ratio of light to medium naphtha may be 50:1 to
1:50,
such as 0.5-20: I or 1:0.5-50. Amounts of alkylate or isomerate (if present)
may be 0.5-
20% such as 1-10%, while amounts of hydrocrackate may be 0.5-30% e.g. 10-30%.
A
preferred blend comprises 20-60% compound A or A' and conversely 80-40%
straight
run gasoline, the sum of these being substantially 100%.
The blends of the invention usually contain in total at least 70% of
saturates, such
as 70-98% or 70-90% or 90-98%.
If desired and especially for aviation gasoline, the blends may contain a
hydrocarbon component which is a saturated aliphatic hydrocarbon of 4-6
carbons and
which has a boiling point of less than 80°C under atmospheric pressure,
such as 20-50°C,
and especially is itself of Motor Octane Number greater than 88 in particular
at least 90
e.g. 88-93 or 90-92. Examples of the hydrocarbon component include alkanes of
4 or 5
carbons in particular iso-pentane, which may be substantially pure or crude
hydrocarbon
fraction from reformate or isomerate containing at least 30% e.g. 30-80% such
as 50-
70%, the main contaminant being up to 40% mono methyl pentanes and up to 50%
dimethyl butanes. The hydrocarbon component may be an alkane of boiling point
(at
atmospheric pressure) -20°C to +20°C e.g. n and/or iso butane
optionally in blends with
the CS alkane of 99.5:0.5 to 0.5:99.5, e.g. 88:12 to 75:25. n Butane alone or
mixed with
isopentane is preferred, especially in the above proportions, and in
particular with a
volume amount of butane in the composition of up to 20% such as 1-15% e.g. 1-
8, 3-8
or 8-15%, especially 1-3.5%.
The hydrocarbon component boiling less than 80°C, in particular
isopentane, may
also be present in compositions of the invention which contain at least one
compound A
or A', of at least 10 carbon atoms, in particular those boiling at
160°C or above, such as
A1, and A12-14. Relative amounts of these compounds A or A' to the low boiling
component e.g. isopentane, may be 1-9:9-1 such as 5-9:5-I, especially with
less than
9
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
20% of A or A' in the composition.
Cycloaliphatic hydrocarbons e.g. of S-7 carbons such as cyclopentane or
cyclohexane may be present but usually in amounts of less than 15% of the
total e.g. 1-
10%.
The compositions of the invention also preferably contain as component (d) at
least
one olefin, (in particular with one double bond per molecule) which is a
liquid alkene of
5-10 e.g. 6-8 carbons, such as a linear or branched alkene e.g. pentene,
isopentene
hexene, isohexene or heptene or 2 methyl 2 pentene, or a mixture comprising
alkenes
which may be made by cracking e.g. catalytically or thermally cracking a
residue from
crude oil, e.g. atmospheric or vacuum residue; the mixture may be heavy or
light
catalytically cracked spirit (or a mixture thereof). The cracking may be steam
assisted.
Other examples of olefin containing mixtures are "C6 bisomer", catalytic
polymerate, and
dimate. The olefinic mixtures usually contain at least 10% w/w olefins, such
as at least
40% such as 40-80% w/w. Preferred mixtures are (xi) steam cracked spirit (xii)
catalytically cracked spirit (xiii) C6 bisomer and (xiv) catalytic polymerate,
though the
optionally cracked catalytically spirits are most advantageous. Amounts in the
total
composition of the olefinic mixtures especially the sum of (xi) - (xiv) (if
any present)
maybe 0-55, e.g. 10-SS or 18-37 such as 23-35 or 20-55 such as 40-55% Amounts
of
(xi) and (xii) (if present) in total in the composition are preferably 18-55,
such as 18-35,
18-30 or 35-55% (by volume).
The olefin or mixture of olefins usually has an MON value of 70-90, usually a
RON value of 85-95 and a ROAD value of 80-92.
The volume amount of olefins) in total in the gasoline composition of the
invention may be 0% or 0-30%, e.g. 0.1-30% such as 1-30% in particular 2-25
e.g. 2-
14% (especially 3-10). Usually the composition contains at least 1% olefin and
a
maximum of 18% or especially a maximum of 14%, but may be substantially free
of
olefin.
The compositions may also contain as component (e) at least one aromatic
compound, preferably an alkyl aromatic compound such as toluene or o, m, or p
xylene
or a mixture thereof or a trimethyl benzene. The aromatics may have been added
as
single compounds e.g. toluene, or may be added as an aromatics mixture
containing at
least 30% w/w aromatic compounds such as 30-100% especially 50-90%. Such
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
mixtures may be made from catalytically reformed or cracked gasoline obtained
from
heavy naphtha. Example of such mixtures are (xxi) catalytic reformate and
(xxii) heavy
reformate or heavy steam cracked spirit. Amounts of the single compounds e.g.
toluene
in the composition may be 0-35%, such as 2-33% e.g. 10-33%, while amounts of
the
aromatics mixtures especially the total of the reformates (xxi) & (xxii) (if
any) in the
composition may be 0-50%, such as 1-33% e.g. 2-15% or 2-10% or 15-32% v/v, and
total amount of reformates (xxi), (xxii) and added single compounds (e.g.
toluene) may
be 0-50% e.g. 0.5-20% or 5-40, such as 15-35 or 5-25% v/v.
The aromatics usually have a MON value of 90-I 10 e.g. 100-110 and a RON value
of 100-120 such as 110-120 and a ROAD value of 95-110. The volume amount of
aromatic compounds in the composition is usually 0% or 0-50% such as less than
40%
or less than 28% or less than 20% such as I-50%, 2-40%, 3-28%, 4-25%, 5-20%
(especially 10-20%), 4-10% or 20-35% especially of toluene. The gasoline
composition
may also be substantially free of aromatic compound. Amounts of aromatic
compounds
of less than 42%, e.g. less than 35% or especially less than 30% or 18% are
preferred.
Preferably the amount of benzene is less than 5% preferably less than 1.5% or
1% e.g.
0.1-1% of the total volume or less than 0.1% of the total weight of the
composition.
The compositions may also contain as component (f) at least one oxygenate
octane
booster, usually of Motor Octane Number of at least 96-105 e.g. 98-103. The
oxygenate
may be any organic liquid molecule containing and preferably consisting of, CH
and at
least one oxygen atom e.g. 1-5 of by less than 225°C. The octane
booster is usually an
ether e.g. a dialkyl ether, in particular an asymmetric one, preferably
wherein each alkyl
has 1-6 carbons, in particular one alkyl being a branched chain alkyl of 3-6
carbons in
particular a tertiary alkyl especially of 4-6 carbons such as tent-butyl or
tert-amyl, and
with the other alkyl being of 1-6 e.g. 1-3 carbons, especially linear, such as
methyl or
ethyl. Examples of such oxygenates include methyl tertiary butyl ether (MTBE),
ethyl
tertiary butyl ether and methyl tertiary amyl ether. The oxygenate may also be
a cyclic
ether, in particular with 5 or 6 ring atoms in the or each ring, such as furan
or
tetrahydrofuran and its lower alkyl e.g. methyl derivatives. The oxygenate may
also be
an alcohol of 1-6 carbons e.g. ethanol. The oxygenate may also be an organic
carbonate
e.g. a dialkyl carbonate with 1-3 carbon atoms in each alkyl e.g. dimethyl
carbonate.
The volume amount of the oxygenate may be 0 or 0-25% such as 1-25%, 2-20%,
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
2-10% or 5-20% especially 5-15%, but advantageously less than 3% such as I-3%
(especially of MTBE and/or ethanol). The oxygenate may also be substantially
absent
from the composition or gasoline of the invention, which is thus a
substantially
hydrocarbon fuel.
The present invention also provides a formulated unleaded gasoline comprising
a
blend composition of the invention comprising component (a) and (b) and
usually at least
one gasoline additive, e.g. as described above, in particular with the
gasoline comprising
less than 5%, e.g. less than 4% of triptane or 223 trimethyl pentane.
The blend of the invention contains at least one component (a) and component
(b)
and, (optionally (c) to (f), as well, and the formulated unleaded gasoline
also contains at
least one gasoline additive e.g. a motor gasoline or aviation gasoline
additive, for
example as listed in ASTM D-4814 the contents of which is herein incorporated
by
reference or specified by a regulatory body, e.g. US California Air Resources
Board
(CARB) or Environmental Protection Agency (EPA). These additives are distinct
from
the liquid fuel ingredients, such as MTBE. Such additives may be the lead free
ones
described in Gasoline and Diesel Fuel Additives, K Owen, Publ. By J.Wiley,
Chichester,
UK, 1989, Chapters 1 and 2, USP 3955938, EP 0233250 or EP 288296, the contents
of
which are herein incorporated by reference. The additives maybe pre-combustion
or
combustion additives. Examples of additives are anti-oxidants, such as one of
the amino
or phenolic type, corrosion inhibitors, anti-icing additives e.g. glycol
ethers or alcohols,
engine detergent additives such as ones of the succinic acid imide,
polyalkylene amine or
polyether amine type and anti-static additives such as ampholytic surface
active agents,
metal deactivators, such as one of thioamide type, surface ignition inhibitors
such as
organic phosphorus compounds, combustion improvers such as alkali metal salts
and
alkaline earth metal salts of organic acids or sulphuric acid monoesters of
higher
alcohols, anti valve seat recession additives such as alkali metal compounds,
e.g. sodium
or potassium salts such as borates or carboxylates e.g. sulpho succinates, and
colouring
agents, such as azodyes. One or more additives (e.g. 2-4) of the same or
different types
may be used, especially combinations of at least one antioxidant and at least
one
detergent additive. Antioxidants such as one or more hindered phenols e.g.
ones with a
tertiary butyl group in one or both ortho positions to the phenolic hydroxyl
group are
preferred in particular as described in Ex. l hereafter. In particular the
additives may be
12
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
present in the composition in amounts of 0.1-100ppm e.g. 1-20ppm of each,
usually of
an antioxidant especially one or more hindered phenols. Total amounts of
additive are
usually not more than 1000ppm e.g. 1-IOOOppm.
The compositions and gasolines are free of organolead compounds, and usually
of
manganese additives such as manganese carbonyls.
The compositions and gasolines may contain up to 0.1% sulphur, e.g. 0.000-
0.02%
such as 0.002-0.01 %w/w.
The gasoline compositions of the invention usually have a MON value of 80 to
105
such as 85-105, 85-90, 90-105 or 93-105 e.g. but especially 94-102. The RON
value is
usually 90-115 e.g. 102-115 such as 98-112 or 105-112, or 93-98 e.g. 94.5-
97.5, or 97-
101 while the ROAD value is usually 85-110 or 85-107 e.g. 98-106 or 102-108 or
85-
95. Preferred gasoline compositions have MON 83-93, RON 93-98 and ROAD 85-95
or MON 85-90, RON 94-101 and ROAD 89-96 but especially MON 93-98, RON 102-
108, ROAD 98-106, or MON 95-105, RON 102-I 15 e.g. 108-115 and ROAD 98-106.
1 5 The Net calorific value of the gasoline (also called the Specific Energy)
is usually at least
18000 Btu/lb e.g. at least 18500, 18700 or 18,900 such as 18500-19500, such as
18700-
19300 or 18900-19200; the calorific value may be at least 42MJ/kg e.g. at
least 43.5
MJ/kg such as 42-45 or 43-45 such as 43.5-44.SMJ/kg. The gasoline usually has
a
boiling range (ASTM D86) of 20-225°C, in particular with at most 5%
e.g. 0-5% or 1-
3% boiling in the range 161-200°C. The gasoline is usually such that at
70°C at least
10% is evaporated while 50% is evaporated on reaching a temperature in the
range 77-
120°C preferably 77-116°C and by 185°C, a minimum of 90%
is evaporated. The
gasoline is also usually such that 8-50% e.g. 10-40% may be evaporated at
70°C, 40-
74% at 100°C, 70-99.5% at 150°C and 90-100% may be evaporated at
180°C; preferably
46-65% has been evaporated by 100°C. The Reid Vapour Pressure of the
gasoline at
37.8°C measured according to ASTM D323 is usually 30-120, e.g. 40-100
such as 61-80
or preferably 50-80, 40-65, e.g. 45-65, 40-60 or 40-SOKpa. Especially the
gasoline or
blend has RON value of 90-115, MON value of 85-105, aromatics content of less
than
35%, olefins content of less than 14%, benzene less than 1%, % evaporated at
70°C 10-
40%, % evaporated at 100°C 40-74%, % evaporated at I50°C 70-
99.5% and RVP of
40-60 kPa.
The gasoline compositions, when free of any oxygenates usually have a H:C atom
13
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
ratio of at least 1.8: I e.g. at least 2.0:1 or at least 2.1 or 2.2:1, such as
1.8-2.3: I or 2.0-
2.2:1. Advantageously the gasoline composition meets the following criteria.
Atom H:C x [1 + oxy] x [ Net Heat of Combustion + ROAD] >_ y,
200
wherein Atom H:C is the fraction of hydrogen to carbon in the hydrocarbons in
the
composition, oxy means the molar fraction of oxygenate, if any in the
composition, Net
Heat of Combustion is the energy derived from burning l 1b (454g) weight of
fuel (in
gaseous form) in oxygen to give gaseous water and carbon dioxide expressed in
Btu/lb
units [MJ/kg times 430.35], and y is at least 350, 380, 410 or 430, in
particular 350-440
e.g. 380-420 especially 400-420.
Among preferred blends of the invention are unleaded blends comprising as
component (a) at least 5 or 10% of at least one individual compound A or A'
and
component (b) as defined above, with the proviso that when the compound A or
A' is an
alkane of 9 or 10 carbon atoms, then blend contains at least 10% of an alkane
of 6 or 7
carbons of MON at least 70 and RON at least 90, and preferably contains less
than 5% in
total of 2,2,3-trimethyl pentane and 2,2,3-trimethyl butane.
Preferred formulated unleaded gasolines of the invention comprise at least one
gasoline additive and the preferred unleaded blend above, with the proviso
when the
compound A or A' is an alkane of 9 or 10 carbon atoms, the blend preferably
contains
less than 5% in total of 2,2,3-trimethyl pentane and 2,2,3-trimethyl butane.
Preferred blends and gasolines of the invention can have MON values of 94-105
(e.g. 97-105), RON values of 103-I 15 (e.g. 107-115), ROAD values of 98-I 10
(e.g. 102-110), compound A or A' contents of 30-60% e.g. 40-60% (comprising 1
or 2
compounds A or A' especially A1 and/or A2), total naphtha contents of 35-65%
(e.g.
35-55%) and 1-5% butane, the blends containing 1-8% e.g. 2-6% aromatics, 0-1%
olefins and 91-99% (e.g. 94-98%) saturates. These are substantially aliphatic
blends and
gasolines of very high octane numbers, without the use of oxygenates such as
MTBE,
and also substantially saturated.
Other very high octane blends and gasolines of the invention can have MON
values
of 94-102 e.g. 94-99, RON values of 105-115, ROAD values of 99-107, compound A
or
A' contents of 30-60% e.g. 30-50% (comprising 1 or 2 compounds A or A'
especially
Al and/or A2), medium naphtha contents of 5-30% and contents of total olefinic
fraction
14
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
such as steam cracked spirit of 30-SO% and I-S% butane, the blends containing
10-2S%
aromatics e.g. 12-18% aromatics, 4-14% olefins e.g. 6-12%, and 60-90% such as
70-
80% saturates. These high octane materials are obtained without the use of
oxygenates.
Further blends and gasolines of the invention can have MON values of 84-90,
RON values of 93-98, ROAD values of 86-94, and contain compound A or A' in
amount
of 1 S-3S% (especially of A2), total naphtha of 40-6S% and olefinic fractions
such as
steam cracked spirit of 1S-45% and 0 or 1-S% butane, with aromatic contents of
S-2S%
such as 10-18% olefin contents of 2-14% and saturate contents of 70-90%.
Other blends and gasolines of the invention can contain 10-3S% compound A or
A' (especially A2), and naphtha 30-50%, hydrocrackate 10-30% alkylate and/or
isomerate 2-10%, and reformate 3-12%.
Other blends and gasolines of the invention can contain 10-35% compound A or
A' (especially A2) and 3-12% reformate, 1-20% light naphtha/straight run
gasoline, as
well as alkylate and isomerate, the blend and gasoline preferably containing
at least 70%
of saturates.
The invention can provide motor gasolines, in particular of 91, 95, 97, 98 and
110
RON values, with desired high Octane Levels but low emission values on
combustion in
particular of at least one of total hydrocarbons, NOx, carbon monoxide, and
carbon
dioxide, especially of both total hydrocarbons and carbon dioxide. Thus the
invention
also provides the use of a compound A particularly A1 or A2 in unleaded
gasoline of
MON at least 80 e.g. 80 to less than 98, e.g. as an additive to or component
therein, to
reduce the emission levels on combustion, especially of at least one of total
hydrocarbons, NOx, carbon monoxide and carbon dioxide especially both of total
hydrocarbons and carbon dioxide. The invention also provides a method of
reducing
emissions of exhaust gases in the combustion of unleaded gasoline fuels of MON
of at
least 80 which comprises having at least 10% component (a), in particular Al
or A2,
present in the fuel which is a gasoline of the invention. The invention also
provides use
of an unleaded gasoline of the invention in a spark ignition combustion engine
to reduce
emissions of exhaust gases. In the compositions, gasolines, methods and uses
of the
invention the component (a) is preferably used in an emission-reducing
effective amount.
The compositions of the invention may be used in supercharged or turbocharged
engines, or in normally aspirated ones. The compound A, preferably A 1 or A2,
can
IS
WO U1/2173g CA 02385720 2002-03-22 pCT/GB00/03569
reduce one or more of the above emission levels better than a mixture of
aromatics and
oxygenate at similar Octane Number and usually decrease the fuel consumption
as well.
The gasolines of the invention may be used in internal combustion spark
ignition
engines. They may be used to power moving vehicles on land and/or sea and/or
in the
air; the invention also provides a method of moving such vehicles by
combustion of a
gasoline of the invention. The vehicle usually has a driver and especially
means to carry
at least one passenger and/or freight.
The engine sizes for motor gasoline use are usually at least 45cc e.g. 45-
10000cc
e.g. at least 200cc, such as 500-10000cc, in particular 950-2550, such as 950-
1550, or
1250-1850cc, or 2500-10000cc such as 2500-5000 or 5000-9000cc. The engines
have
at least 1 cylinder, but preferably at least 2 or 3 cylinders, e.g. 3-16,
especially 4-6 or 8
cylinders; each cylinder is usually of 45-1250cc e.g. 200-1200cc, in
particular 240-520cc
or 500-1000cc. The engines may be 2 stroke engines, but are preferably 4
stroke.
Rotary engines e.g. of the Wankel type may be used. The motor engines may be
used to
power vehicles with at least 2 wheels e.g. 2-4 powered wheels, such as motor
bicycles,
tricycles, and 3 wheeled cars, vans and motor cars, in particular those
vehicles legislated
for use on a public highway but also ofProad e.g. 4 wheeled drive vehicles,
sports cars
for highway use, and racing cars, including drag racing cars and track racing
cars. Power
from the engine will preferably be connected to the driving wheels via a
gearbox and
clutch system, or other form of drive train system, to achieve the transition
from a
stationary to a mobile state. The engine and drive train will best allow a
range of actual
vehicle road speed of between 1-350km/h, preferably between 5-130km/h and
allow for
continuous variation of speed thereof. The road speed of the vehicle is
usually reduced
by a braking mechanism fitted to the vehicle, the braking being generally
applied by
friction. The engine may either by air or water cooled, the air motion induced
by a
moving vehicle being used to directly, or indirectly cool the engine. The
vehicle
comprises a means to facilitate a change of vehicle direction, e.g. a steering
wheel or
stick. Usually at least 10% of the vehicle distance travelled is carried out
at greater than
Skm/h.
The engines using aviation gasoline are usually in piston driven aircraft,
i.e. with at
least one engine driving a means for mechanically moving air such as at least
one
propeller. Each engine usually drives at least one propeller driving shaft
with 1 or 2
16
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
propellors. The aircraft may have 1-10 propellers e.g. 2-4. The aircraft
engines usually
have at least 2 cylinders, e.g. 2 to 28 cylinders, each of which is preferably
greater than
700cc in volume, such as 700-2000cc e.g. 1310cc. The total engine size is
usually 3700-
SOOOOcc e.g. 3700 to 12000cc for single or twin engined passenger light
aircraft, 12000
to 45000cc for 2 or 4 engined freight or airline use (e.g. 15-200 passengers,
such as 50
to 150 passengers). The engines may have an engine power to weight ratio of at
least
0.3Hp/lb wt of engine, e.g. 0.3-2Hp/lb, and may have a power to cylinder
volume of at
least 0.5 (Hp/cu.in) e.g. 0.5-2. Cylinders may be arranged in rows, V
formation, H
formation, flat ('horizontally opposed') or radially around a common propeller
drive
shaft. One or more rows/circles of cylinders may be used, e.g. flat 2, flat 4,
flat 6, V 12, 1
2 or 3 circles of 7 cylinders etc. Every cylinder has one and more preferably
at least two
spark plugs. A gear system may optionally be used to drive the propeller and
or a
supercharger. Alternatively, an exhaust turbo charger may also be present.
Exhaust
outlets may be individual or run into a common manifold and preferably point
in the
1 5 opposite direction to forward flight. Fins may be present on the exterior
of the engine
for air cooling. Greater than 90% of the distance travelled by the engine,
when in use, is
usually spent at 500 feet or more above ground level. Typically, during
greater than
90% of the time when the engine is running, the engine operates at above
1000rpm e.g.
between 1000 to 3500 rpm.
The aircraft usually has at least one tank having a capacity of at least 1001,
especially with a total capacity of at least 10001. Small and micro-light
aircraft may have
tanks substantially smaller in capacity but can operate on the unleaded
gasoline
described.
The gasolines of the invention may be made in a refinery by blending the
ingredients to produce at least 200,0001/day of gasoline such as 1-lOmillion
1/day. The
gasoline may be distributed to a plurality of retail outlets for motor
gasoline, optionally
via wholesale or bulk outlets e.g. holding tanks, such as ones of at least 2
million 1
capacity e.g. 5-15 million 1. The distribution may be by pipeline or in tanks
transported
by road, rail or water, the tanks being of at least 50001 capacity. At the
retail sites e.g.
filling station, the motor gasoline is dispensed to a plurality of users, i.e.
the drivers of
the vehicles, e.g. at a rate of at least 100 or 1000 different users per day.
For aviation
use, the gasoline is usually made in a refinery to produce at least 1000
barrels per day (or
17
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
100,0001/day) such as 0.1-2 million 1/day. The avgas is usually distributed by
tanker by
road, rail or water, or pipelines directly to the airport distribution or
holding tanks, e.g.
of at least 300,0001 capacity, from whence it is distributed by pipeline or
tanker (e.g. a
mobile refuelling bowser to fuel a plurality of aircraft, e.g. at least 5/day
per tank; the
aircraft may have one or more on-board tank each of at least 1001 capacity.
The present invention is illustrated in the following Examples.
Examples 1-7
Various unleaded blends are made up with compound Al and/or A2 and various
refinery streams as shown in Table 1.
7 Formulated gasolines are made, each containing one of the above blends and a
l5mg/1 of a phenolic antioxidant 55% minimum 2,4 dimethyl-6-tertiary butyl
phenol 15%
minimum 4 methyl-2, 6-ditertiary-butyl phenol with the remainder as a mixture
of
monomethyl and dimethyl-tertiary butyl phenols.
In each case the gasolines are tested for MON and RON, and their Reid Vapour
Pressure at 37.8°C. The results are shown in table 1, which also shows
their analyses
and distillation profile (according to ASTM D86).
Example 8
The emission characteristics on combustion of the formulated gasolines of Ex.
l-7
are determined.
The fuels are tested in a single cylinder research engine at a speed/load of
50/14.3rps/Nm with a LAMBDA setting of 1.01, and the ignition setting is
optimised for
the comparative blend. The emissions of CO, COZ total hydrocarbons, Nox, are
measured from the exhaust gases. The results are averaged and show a reduction
in the
emissions compared to a standard unleaded fuel.
Example 9 and Comparative Ex. A
An unleaded blend was made up with 22446 pentamethyl heptane, blended with
various refinery streams as shown in Table 3. Comp Ex. A, with heavy reformate
meets
the Europe 2005 requirement for high octane fuel with RON 97.0, MON 86.3 RVP
at
37.8°C 54.7 kPa distillation profile according to ASTM D86, 10% evap,
at 52.9°C 50%
at 107.0°C and 90% at 166.1 °C.
2 formulated gasolines were made, each containing one of the above blends and
l5mg/1 of the phenolic antioxidant used in Ex. l-7.
18
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
In each case the gasolines were analysed. The results are shown in table 3.
The emission characteristics on combustion of the formulated gasolines of Ex.
9
and Comp. A were determined.
The fuels were tested as in Ex. I-7 in a single cylinder research engine at a
speed/load of 20/7/2rps/Nm with LAMBDA setting of I.OI, and the ignition
setting was
optimised for the comparative blend A. The emissions of CO, COZ total carbon
oxides,
total hydrocarbons, NOX were measured from the exhaust gases as was the Fuel
Consumption (expressed in g/h'Whr). The results were averaged and compared to
the
comparative Ex.A. The degrees of change were as given in Table 4.
15
25
19
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
Table 3
Comp 8
A
Base
Fuel
Formulation % v/v
Butane 3 3
Full range catalytically20 20
cracked spirit
Alkylate 40 40
Light hydrocracked 7 7
spirit
Full range steam 10 10
cracked spirit
Heavy reformate 20
2,2,4,4,6-Pentamethylheptane 20
Density kg/1 0.7487 0.7264
C:H I : 1.8891 : 2.076
C% w/w 86.4 85.25
H% w/w 13.6 14.75
Benzene % v/v 0.6 0.6
Aromatics % v/v 29.4 9.4
Olefins % v/v 9.0 9.0
Table 4
Example CO C02 COx THC NOx Fuel
Economy
Comp 0% 0.0% 0.0% 0.0% 0.0% 0.0%
A
9 -1.7% -2.7% -2.7% 3.1% -4.5% 0.1%
Figures denote % change relative to base (Fuel (Comp.A)
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
~d- t~~t ~ M ,~N O O M ~n~ ~nO N N p0
O M ~ O N ,riN ~n~ON O ~ M o0 M O
N N M N ~ 00 O~oo~nO~M ~nI~ OvO
O
N ~f'N
~O O W O N ~ -~ O OvO ~ O ~ O O M O
O ' O N O
tnN ~1.~ ~ ~ M ~ Ov~ ~ ~ O O Oyn ~ O O O
O
O O ~ I~ ~ON N O O O ~nI~O Ov o0N O
' ~
~ N o0' 00~, O~ ~ N M v1~OO O ~OO~~O Ov O
N ~ r- r oo Ovo0v~Ov~ ~ a1 OvO
O
N ~ M ~O ~ ,-,M O O O ~ VlO O O M
O O O
O ~ O
~ V N ~ M ~ ~ O ~ ~ ~ ~ O
O ~ Iw0 ~ N ~ ~ ~ O O '~tO O ~OM
O ~ O O vi ~ voO O M O o0 (VO
N O v0 ~ O O~ ~ Q\~ '-"'M ~D~ QvO
O N ~ N N o0 O O O ~ 00OvO o0~,~
(~.~ ~tO ~ ~ ~ ~ ~ N
~ ~ ~'
3
. v
_
'~z ~ ~ ~ ~ ~ ~ _ ~ ' s s s
~ ~ z ~-~ ~ ~ ~ o 0 0
~ '~'~~ y ~' ~ o z ~ ~ o
'~ o
~ ~ x ~ o o ~ ~
H c~U U ~ ;~x x Q ~ s s s x ~ x x w w w w as
21
CA 02385720 2002-03-22
WO 01/21738 PCT/GB00/03569
Example 10
An unleaded blend was made up with 2,2,3,3-tetramethyl butane (12%), alkylate
(45%), reformate (6%), isomerate (20%) and naphtha i.e. a straight sum
gasoline (17%).
The tetramethyl butane contained 86.6%, 2,2,3,3-tetramethyl butane, 3.6% 2,2,4-
trimethyl pentane 3.7%, cis 3 methyl hexene 2 and 6% unknown and high boilers.
It was
made substantially according to the procedure of Marker and Oakwood J. Amer.
Chem.
Soc. 1938, 60, 258.
The blend was mixed with l5mg/1 of the phenolic antioxidant used in Ex. l-3.
The
formulated gasoline was tested for MON and RON which were found to be 88.7 and
93.0 respectively, ROAD value 90.85.
20
30
22
