Note: Descriptions are shown in the official language in which they were submitted.
12~9871
3ACRGROUND OF THE r NVENTION
This invention i~ diracted to an anti-
fouling fuel composition. More specifically, the
present invention is directed at a fuel compo~ition
hav$ng particular applicability in minimizing and/or
prsventing injector fouling in gasoline engines
equipp~d with electronically controlled multiport fuel
injector~.
Over the past several year~, improvements
have been mad~ in the performance of internal combu~-
tion engine~. one of the mo~t significant improvements
which ha~ b~en made has been the wide~pread us- o~ fuel
in~ection to improve the perfor~ance and fuel economy
of int-rnal combustion engin-~. Whila carburetor-
equipped internal combustion engines admix the air and
fu-l for di~tribution through a m~n~fold to all of the
cylinder~, in a fu-l injected engina the fuel i3 in-
~ect~d into the manifold clos~ to the intak- valve of
each cylind-r for combustion. Fuel injection ~y~tems
ar- of two ba~ic type , mechanically controlled and
electronically controlled. ~he early fuel injected
engine~ wer- controlled mechanically, i.e., the opera-
tion of each injector wa~ controlled by pres~ure.
Recently, however, the u9e of electronically con-
trolled fuel injection engine~ has bacome increasingly
widespread. In an electronically controlled fuel
injection system sensors disposed in the exhau~t are
employed to maintain the air to fuel ratio within
narrow limit~. Electronically controlled fuel in-
jection ~y-~temY offer the same performance and fuel
economy benefits that would be achieved with mechani-
~k
1~987~
cally controlled fuel injection systems and also serveto more closely regulate fuel-air mixtures to thereby
enable the catalytic converter to oxidize carbon
monoxide and hydrocarbons to carbon dioxide and
simultaneously to reduce nitrogen oxide and thus meet
emi33ions control legislation. Such legislation
imposing as it did strict control of exhaust pollutants
utimately led to the development and widespread appli-
cation of new technologies such as electronic fuel
injection.
It has been found that the electronically
controlled fuel injector systems have small port
opening3 which are prone to fouling by deposits. These
deposits are believed to occur, at least in part, by
gasoline and oil vapor, which i~ present in close
proximity to the injector tip, becoming baked onto the
hot surfaces of the injector pintle and OQ the ~urfaces
of the annulus suErounding the pintle when the engine
is qhut off. ThesQ deposits restrict the fuel flow to
that particular cylinder. Thi~, in turn, causes a
sensor disposed in the exhaust to detect a higher than
desired oxygen to fuel ratio. The sensor will attempt
to correct this condition by increasing the amount of
fuel injected into all of the cylinders~ This, in turn,
will re~ult in a richer than desired fuel to air ratio
in the exhaust. The sensor then will attempt to
correct this by decreasing the amount of fuel injected
into each cylinder. This cyclical adjustment of the
fuel to air ratio ranging between too lean a mixture
and too rich a mixture can at times result in poor
operating performance of the vehicle. In addition,
close tole~ances in this new type of injector and con-
currently higher underhood temperature also tend to
enhance deposit formation resulting in poor vehicle
i2~98'71
-- 3 --
driveability and exhaust pollut-ant emission levels
which exceed the maximum levels set by emisisons
control legislation.
It has been found that conventional gasoline
detergents, which have proven effective in preventing
and/or eliminating carburetor deposits are not par-
ticularly effective in removing and/or preventing
deposit build-up that may occur in electronically con-
trolled fuel injection system~. Pre~ently available
methods for removing deposits from fuel injector
orifices typically comprise either mechanically
cleaning the injectors or the addition to the fuel of
relatively large quantitie~ of particular additives.
Mechanical cleaning, which may involve either the com-
plete removal of the injector for manual deposit re-
moval or the use of polar solvents for flu~hing the
depo-~it-Q free, i3 not desired becaus~ of the rela~
tively high cost and inconvenience. Currently avail-
able additive~ are not particularly de~irable becau-~e
product recommendation indicate they muqt be used at
relatively high concentrations, i.e. about one to about
two tons par thousand barrel of fuel.
To be u~eful commercially a gasoline
additive for reducing and/or preventing injector port
foul~ng mu~t be effective at low concentration, mu~t
not significantly affect the combu~tion characteri-~tic~
of the fuel and must not foul the catalytic converter
catalyst.
The additive also should not promote
exce~sive emulsi~ication, and should not promote the
formation of two organic phases.
~Z~987~
-- 4 --
Additives have been added to gasoline to
improve certain properties of the fuel. U.S. Patent
~Jo. 3,387,953 is directed at the use of
organo-substituted nitrogen oxides, particularly amine
oxides for rust inhibition and ac anti-icing agents in
gasoline. Several representative formulas for amine
oxides are given including the following:
R2
I
R~ N - > O
R3
where Rl is C6-C24 alkyl, aryl, cycloaliphatic,
heterocyclic, subqtituted alkyl or substituted aryl;
and R2 and R3 are the same or different and are Cl-C2~
alkyl, aryl, sub~tituted alkyl or aryl, cycloaliphatic
or heterocylic. R2 and R3 preferably comprise hydroxy
substituted alkyls. These compound3 typically are
added to gaYoline in a concentration within the range
of about 2.0 to about 100 pound~ of amine oxide per
1,000 barrels of gasoline (ptb). Among the most
preferred additives is bis(2-hydroxy e~hyl) cocoamine
oxide.
U.S. Patent No. 3,594,139 i~ directed at a
rust-inhibitor concentrate that can be blended with
ga~oline year-round including amine oxide~ having the
aforementioned formula, with a particularly preferred
amine oxide compri~ing bis(2-hydroxy ethyl) cocoamine
oxide. The concentrate also comprises a liquid
aromatic C7-Clo hydrocarbon and an aliphatic monohydric
or dihydric alcohol having from about 6 to about 13
carbon atoms. Preferred aromatic hydrocarbons comprise
ortho, meta and mixed xylenes. Preferred aliphatic
129987~
alcohols comprise C6-C13 oxo alcohols. ~he examples
disclose the combination of xylene, bis(2 hydroxyethyl)
cocoamine oxide, and C8 oxo alcohols.
The amine oxides described above have been
typically used to inhibit rust and carburetor icing.
While these compound were used commercially during the
late 1960's and early 1970' , their use in the United
States was discontinued as more effective additives
were found. The use of these compounds had been dis-
continued in the United States well before the develop-
ment of electronically controlled, fuel injected
engines.
It has been discovered that use of amine
oxides at concentration~ generally higher than that
which previously had been used for rust inhibition
would be effective in preventing and/or reducing
injector fouling in multiport fuel injected engines.
However, when amine oxides are used at these higher
concentration~ they tend to act as emulsifiers which
bring into the gasoline layer~ water, sediment and
impuritie~ which may have entered the product distribu-
tion system. This prevents nor~al separation of the
gasoline from any water or normally in~oluble
impurities. The admixture of these impurities i9 not
desired with the gasoline, since this would result ir
excessive fuel filter fouling and in poor vehicle
operation. In addition, it i~ believed that formatior
of an emulsion results in undesirable concentration of
the amine oxide additive at the interface. It also hac
been found that the use oE certain solvents to produc~
an additive concentrate having low cloud and pour
points may form two organic laye~S resulting in unever
additive distribution.
1299871
Accordingly, it would be desirable to
provide an additive package ~or gasoline which will be
effective in reducing and/or eliminating fouling
without forming an emulsion with water bottoms and
interfacial solids.
It also would be desirable to pro~ide an
additive package having a demul~ifying agent which is
effective in the presence of both neutral and
basic waters.
It also would be desirable to provide an
additive concentrate which has low cloud and pour
points and which does not result in the formation of
more than one organic layer.
Accordingly, it would be desirable to pro-
ri~e a gasoline additive package which is relatively
inexpen3ive and effective at low concentrations to
reduce and/or eliminate injec~or fouling.
It also would be de~irable to provide a
gasoline additive package which is non-corrosive, non-
deleteriou~ to the catalytt, and does not effect the
combustion characteristics of the fuel.
It also would be de~irable to provide a
gasoline additive package which could be ea~ily added
to the finished gasoline at any point during the
storage and/or distribution system.
1~987~
SUMMARY OF THE INVE~I~ION
The present invention is directed at a fuel
composition for minimizing and/or preventing injector
fouling in a multiport electronically controlled fuel
injected engine. The compo~ition comprises:
A. gasoline
B. an anti-fouling agent having the
formula:
R2
I
Rl -- N --> O
I
R3
where: Rl is C6-C24 alkyl, aryl, cycloaliphatic,
heterocyclic, subqtituted alkyl or substituted aryl;
and R2 and R3 independently are Cl-C24 alkyl, aryl,
substituted alkyl or aryl, cycloaliphatic or
heterocylic; and,
C. a demulsifier comprising one or more of
the following demulsifying agents:
i. a eatty acid alkylamine reaction
product; and,
ii. a solution of oxyalkylated alkyl phenol
formaldehyde resins and polyglycols.
In this composition Rl preferably is C6-C20
alkyl, or alkylated aYyl, and R2 and R3 independently
are Cl-C12 hydroxy substituted alkyl. In a more
i2~9871
-- 8
preferred composition Rl, comprises C8-Clg substituents
derived from fatty acid. The additive preferably is
selected from the group consisting of bis(2-hydroxy
ethyl) cocoamine oxide, bis(2-hydroxy ethyl) tallow
amine oxide, bis(2-hydroxy ethyl) stearyl-amine oxide,
dimethylcocoamine oxide, dimethyl hydrogenated tallow
amine oxide, dimethylhexadecylamine oxide and mixtures
thereof. A particularly preferred additive is bis(2-
hydroxy ethyl) cocoamine oxide. The anti-fouling
agent concentration in the fuel typically may range
between about 0.5 and about 50 ptb (i.e. about 2 to
about 200 ppm, by weight), preferably between about 5
and about 15 ptb (i.e. about 20 to about 60 ppm).
In demulsifying agent (ii) the oxyalkylated
compounds preferably comprise ethylene oxide and
propylene oxide copolymers. The active concentration
of the demulsifyinq agent may range between about 0.025
and about 1~ ptb (about 0.1 and about 40 ppm),
preferably between ahout 0.25 and about 2.0 otb (about
1.0 and 8.0 ppm).
~ fuel composition may comprise:
A. about 2 to about 200 ppm bis(2-hydroxy
ethyl) cocoamine oxide; and,
8. about 0.1 to about 40 ppm of a
demulsifying agent selected from the group consistina
of:
i. fatty acid alkylamine reaction product;
ii. a solution of oxyalkylated alkylphenol
formaldehyde resins and polyglycols; and mixtures of i
and ii.
12C~'9871
A preferred composition comprises:
A. about 20 to about 60 ppm bis(2-hydroxy
ethyl) cocoamine oxide; and,
B. about 1 to about 8 ppm of a demulsifying
agent selected from the aroup consisting of:
i. fatty acid alkylamine reaction product;
ii. a solution of oxyalkylated alkylphenol
formaldehyde resins and polyglycols; and mixtures of i
and ii.
A preferred fuel composition includes an
additive Package comprising:
~ . about 20 ppm to about 60 ppm bis(2-
hydroxy ethyl) cocoamine oxide;
B. about 0.5 ppm to about 4 ppm fatty acid
alkylamine reaction product; and,
C. about 0.5 Ppm to about 4 ppm of a solu-
tion of oxyalkylated alkylphenol formaldehyde resins
and polyglycols.
The present invention also is directed at a
fuel additive concentrate for internal combustion
engines, said additive concentrate comprising:
A. about 5 to about 50 wt.~ bis(2-hydroxy
ethyl) cocoamine oxide;
~2~871
-- 10 --
B. about 0.25 to about 10 wt.~ of a
demulsifying agent selected from the group consisting
of:
i. fatty acid alkylamine reaction product;
ii. a solution of oxyalkylated alkylphenol
formaldehyde resins and polyglycols; and mixtures of i
and ii; and,
C. about 40 to about 95 wt.% solvent.
The qolvent preferably comprises xylene and
a C4+ alcohol, preferably a C4-C12 alcohol, more
preferably a C8 alcohol and most preferably a C8 oxo
alcohol. Where the ratio of the concentration of water
relative to amine oxide exceeds about 0.05, a highly
water and hydrocarbon soluble alcohol, preferably
i~opropanol, also should be added.
DETAILED DESCRIPTION OF THE INVENTION
The present invention i9 directed at a fuel
composition and a gasoline additive package which has
been found to be particularly effective in reducing
and/or eliminating injector fouling. The present in-
vention is directed at a fuel compri~ing:
A. gasoline;
B. an anti-fouling agent having the
following structueal formula:
1~9871
R2
I
R 1 N > O
I
R3
where Rl is C6-C24 alkyl, aryl, cycloaliphatic,
heterocyclic, substituted alkyl, ~ubstituted aryl; R2
and R3 independently are Cl-C24 alkyl, aryl, sub-
stituted alXyl or aryl, cycloaliphatic, heterocyclic,
and mixtures thereaf; and,
C. a demul~ifying agent selected from the
group consisting of:
i. a ~atty acid alkyiamine reaction
2roduct;
ii. a ~olution of an oxyalkylated
alkylphenol formaldehyde resins and polyglycols; and
mixtures thereof.
Prefesred anti-fouling agents include
compounds whe~ein: R1 is C6-C20 alkyl, or al~ylated
aryl; and R2 and R3 independently are hydroxy
substituted Cl-C12 alkyl. Particularly ,oreferred
compounds are compounds wherein Rl comprises a Cg-C1g
substituent. The additive preferably is selected from
the group consisting of bis (2-hydroxy ethyl) coco-
amine oxide, ois(2-hydroxy ethyl~ stearylamine oxide
dimethylcocoamine oxide, dimethyl hydrogenated tallow
amine oxide, dimethylhexadecylamine oxide and mixtures
thereo~. These additives are prepared in accordance
with known techniques, such as disclosed in U.S. Patent
3,387,953. A particularly preferred anti-fouling agent
~1
12~987~
is bis(2-hydroxy ethyl) cocoamine oxide.
The following Comparative Examples and
Examples demonstrate the utility of the anti-fouling
agent in reducing and/or eliminating fuel injector
fouling. In the following Comparative Examples and
Examples, the octane rating of the fuel utilized is the
posted octane rating which is defined as:
Research Octane + Motor octane
COMPARATIVE EXAMPLE I
In this test three 1985 Oldsmobile 98's
having electronically con~rolled, fuel injected, 3.8
liter, six cylinder engines were driven on a commer-
cial, unleaded, 87 octane reference fuel having a
detergent concentration of 8.5 ptb for approximately
3500 miles under the following driving cycle: 0.5 hours
city-type driving, 0.5 hour engine off, 0.5 hour high-
way driving, 0.5 hour engine off. Driveability on all
four vehicles became poor to very poor. The vehicles
then were driven for 300 miles with a commercial
premi~m grade 92 octane unleaded fuel containing 2.S
times the detergent used in the above reference fuel.
Driveability remained unchanged. The data in Table I
below show that there wa~ still a marked reduction in
fuel flow indicating that a high level of deposit was
unaffected by the detergent even at the high treat
rate. The percent fuel flow reduction was determined
by measuring the volume of a mineral spirit tnat flowed
through the injector under predetermined standardi~ed
8~71
conditions, including fuel pressure, puise width and
duty cycle. The percent reduction is calculated using
the formula:
% Reduction = Vclean ~ Vdirty x 100%
Vcleab
where Vclean and Vdirty are the mea~ured volumes of
mineral spirit passed through the clean and dirty fuel
injectors.
871
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~2~387~
Fro~ Table I it can be seen that this con-
ventional, known carburetor detergent was ineffective
in removing deposits from injector ports and in fact
permitted deposits to form.
COMPARATIVE EXAMPLE r I
A 1985 Chrysler LeBaron equipped with a 2~2
liter turbocharged engine having electronically con-
trolled fuel injection wa~ driven for 1300 miles on a
mileage accumulation dynamometer using a typical
regular grade, 87 octane, unleaded, detergent-free
gasoline. The driving was based on repetition of the
following cycle: 30 minutes city driving, 30 minutes
engine off, 30 minutes highway driving, 30 minutes
engine off. The driveability became very poor as
typified by rough idle and severe he~itation. The
hydrocarbon emissions measured before the catalytic
converter were 321 pp~ at engine idle. The injector
fouling was mea~ured u~ing a pres~ure differential
test. In this test the fuel rail is pre~surized to 49
psig and an injector i~ pulsed for 0.5 seconds. The
pre~sure drop, or leakdown P, is indicative of how
readily the fuel flows, i.e., the higher the number,
the less the injector is obstructed. In this vehicle
the pressure differential for a clean injector under
these conditions is 19-22 psig. This data i~ set forth
below in Table II.
EXAMPLE I
Following the test set forth in Comparative
Exa~ple II, the vehicle was refueled with the same fuel
except that the fuel also contained 10 ptb of bis(2-
hydroxy ethyl) cocoamine oxide (HECO1. The vehicle
then was driven on the ~ollowing cycle: 15 ~inutes city
~2~871
- 16 -
driving, 30 minutes highway driving, 15 minutes city
driving, 2 hours enqine off. This test continued until
270 miles were accumulated on the vehicle. At the end
of thiC test period the driveability was very good. The
hydrocarbon emissions at idle before the catalytic
converter were reduced to 200 ppm. The percent in-
jector flow reduction and the pressure differential
were significantly improved as set forth in Table II.
From the data of Example I and Table II it
can be seen that the use of a relatively low concen-
tration of HECO was able to produce a significant im-
provement in driveability. The idle emissions were
significantly reduced and the pressure differential and
percent flow reduction of the flow injectors were re-
turned to "as new" conditions after a relatively few
miles of driving.
12~9871
-- 17 --
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~2~3871
- 18 -
As shown by the following Comparative
Example3 and Example, bis (2-hydroxy ethyl) cocoamine
oxide also was effective in preventing the build-up of
fuel injector tip deposits.
COMPARATIVE EXAMPLE III
In this Comparative Example, four 1985
Chrysler Le3arons equipped with four cylinder,
electronically controlled, fuel injected, turbocharged,
2.2 liter engines were driven on mileage accumulation
dynamometers under the following conditions: 0.5 hour
city-type driving, 0.5 hour engine off, 0.5 hour high-
way type driving and 0.5 hour engine off for 4,000
miles. The control car~ ran on a regular grade, 87
octane, detergent-free, unleaded fuel. Following the
test, the percent flow reduction was measured u~ing the
procedures previou31y cet forth hereinabove. The teQts
were repeated in four different run~ (same make and
model). The resultQ of the~e tests are set forth in
Table III below.
EXAMPLE II
A 1985 Chrysler LeBaron, similar to that set
forth in Comparative Example III was used in this test
which was conducted under the same condition~ set forth
in that Comparative Example. The gasoline used during
this tect was the same as that used in the control
cars, but with the further addition of 10 ptb of
bis(2-hydroxy ethyl) cocoamine oxide (HECO). The
results of these tests are also set forth in Table III
below. From a review of these tests it can be seen
12~3871
-- 19 --
that the addition of a relatively low concentration of
HECO was able to prevent a significant reduction in the
fuel injector ~low rate.
12~98'71
-- 20 --
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12'`~871
- 21 -
COMPARATIVE EXAMPLE IV
In this test a 1985 Chrysle~ LeBarOn naving
a four cylinder, turbocharged, 2.2 liter engine with
electronically controlled fuel injection was operated
for 2,002 miles on a mileage accumulation dynamometer
simulating alternating driving and engine-off cycles.
The fuel utilized was typical of a regular grade, 87
octane, unleaded fuel containing 8.5 ptb of the same
detergent used in Comparative Example I. ~ollowing the
completion of this te~~t, the percent flow reduction
through the fuel injector ports was measured by the
method previou ly described herein. A3 shown in Table
IV below the use of this conventional carburetor
detergent was ineffective in preventing injector
fouling.
EXAMPLE I r I
A vehicle simila~ to that utilized in
Comparative Example IV was utilized in thi~ Example
under tha same operating condition~. The fuel utilized
was ~imilar but with tha replacement of the conven-
tional carburetor detergent by 10 ptb of bis(2-hydroxyl
ethyl) cocoamine oxide. The vehicle was driven for
9,600 mile~ under the same sequence set forth in
Compa~ative Example IV. The biR(2-hydroxy ethyl)
cocoamine oxide wa~ able to prevent any significant
flow reduction in the fuel injectors as shown by data
pre~ented in Table IV.
i2n~8~71
-- 22 --
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12~9871
From this Table it can be seen that the use
of a relatively low concentration of HECO was able to
prevent any significant buildup of injector tip de-
posits. By comparison, the use of a conventional
carburetor detergent at approximately the same rate
was unable to prevent a relatively rapid deposit build-
up of injector tip depositR.
.
While the data presented above has
demonstrated the utility of the anti-fouling agent in
gasoline, the anti-fouling agent also may be of utility
in other fuels, such as diesel fuel.
While the pre~ently described anti-fouling
agent may be used alone, it also may be desirable to
utilize the present invention in combination with a
demulsifier to facilitate the separation of the
ga~oline from any foreign substances which may be
present in the distribution system, ~uch as water and
sediment.
The water, if any, typically has a pH
ranging from about 7 to about 12. Thus, a demulsifier
for us~ with the anti-fouling agent preferably should
be effective over this pH range. The following
Comparative Exa~ples and Example~ demonstrate the
utility of a demul~ifying agent selected from the group
consi~ting of:
A. a fatty acid alkylamine reaction
product;
B. a solution of oxyalkylated alkylphenol
formaldehyde resins and polyglycols; and mixtures of A
and B above.
12~9871
- 24 -
COMPARATIVE EXAMPLE V
~ n this Comparative Example the effective-
ness of various commercially available demulsifying
agent3 were tested in a 90 wt.% fuel - 10 wt.% water
system. The fuel contained 10 ptb HECO and 1 ptb of
the various additives noted below. The effectivene~is
of the various demul~ifying agents wa~ reached using a
Multiple Contact Emul~ion Test. In thi-~ test 10 ml of
di-~tilled water was added to separate half-pint
bottles. To each bottle was added 100 ml of gasoline.
The bottles were capped, placed on their side~ in
mechanical shaker and agitated at approximately 28
cycles per minute for five minutes. The bottles the
were placed upright in a dark location and allowed t
~tand for 24 hours. The mixture then was rate.
con~idering the gasoline layer, the water layer and the
interface u~ing the rating scale set forth in Table V
below. After the ratings were completed, the gasoline
level was ~ucked down to a level about 1/4 inch above
the emulsion layer without disturbing the interface or
water layer. The withdrawn fuel was discarded and 100
ml of fresh gasoline was added to each bottle. The
mixture was then shaken and the test repeated for a
total of ten times (i.e. a total of about 10 days) or
until it became apparent that the emulsion forming
tendencies had exceeded acceptable levels of 3 or
lower. The trade names of the commercially available
additive utilized, the worst ratings of each mixture
ar.d the time period before each test was terminated are
set forth in Table VI below.
871
- 25 -
TA8LE V
RATING SCALE POR REPORTING EMULSION TEST REUSLTS
RATING DESCRIPTION OF EMULSION
O No skin or interface
1 Slight skin on interface - not completely
continuous
2 Thicker ~kin on interface - ~sually
completely continous
3 Incipient emulsion 1/8 a~ thick as water
layer
4 Emulsion 1/4 a~ thick as water layer
Emulsion 3/8 as thick as water layer
6 Emulsion 1/2 as thick as water layer
7 Emulsion 5/8 as thick as water layer
8 Emulsion 3/4 as thick as water layer
9 Emulsion 7/8 as thick as water layer
Emulsion completely filling water layer
Emulsion of ~aximum severity
12~987~
- 26 -
TABLE VI
EMuLsroN TEST RESUL~S
WORST
DEMULSIFIER DESCRIPTION RATING DAYS RUN
None 6 10
Tolad
T-284 5 4
T-286 4 3
T-292 4~5 5
T-347 4-S 3
T-370 - 5 6
T-500 3-4 6
T-364 6 4
Nalco
5450 6 3
5451 4 S
5452 S 5
5453 4 6
5455 4-5 S
SRD646 6 6
SRD649 6 6
5RD651 4 8
SRD652 6 6
5RD653 6 6
SRD654 6 6
5 or 6RD871 7 6
85BD194 4 5
9871
- 26a -
TABLE VII
DESCRIPTION OF DEMULSIFIERS LISTED IN TABLE VI
Demulsifier Description
Tolad T-292 Oxyalkylated alkylphenol formaldehyde
resins in aromatic hydrocarbons and
isopropanol
Tolad T-347 Oxyalkylated alkylphenol formaldehyde
resins and acylated polyglycols in
aromatic hydrocarbons and methanol
Tolad T-370 Polyglycols in aromatic hydrocarbons
Nalco 5450 Hydrocarbon blend of alkylphenol
formaldehyde resin polyoxyalkylene
polyether
Nalco 5451 Polyglycolated polyol esters and
polyglycolated alkylphenol/formalde-
hyde resin in aromatic solvent
Nalco 5452 Polyolpolyethers and oxyalkylated
alkylphenol/formaldehyde resin
adducts in aromatic solvent
Nalco 5453 Oxyalkylated alkylphenol/formaldehyde
resin adducts in aromatic solvent
Nalco 85BD-194 Ethoxylated nonyl phenol/formaldehyde
resin in hydrocarbon solvent
:`-
PAT 10295-1
87~
EXAMPLE IV
A ga~oline-distilled water sample having 10
ptb of HECO similar to that of Comparative Example V
was utilized. However, in place of the demul~ifiers
listed in Table VI the following additives were used
alone or in combination.
Additive A - Nalco 3BD829 ~uel Dehazer, manufactured
by Nalco Che~ical Company, Oak Brook, Illinois, which
comprises a fatty acid alkylamine re3ction product and
methanol in a hydrocarbon ~olvent.
~'
Additive B - Tolad T-326 manufactured by the Tretolite
Division of Petrolite Corporation, St. Louis, Missouri.
This additive comprises oxyalkylated alkylphenol-
formaldehyd~ resins and polyglycols in aromatic
naphtha. The Multiple Contact Emulsion Test previously
described was utilized to determine the effectiveness
of the~e demulsifiers. These test results are
summarized in Table VIl below.
12~9871
TABLE VII
EMULSION TEST RESULTS
DEMULSIFIER WORST
DESCRIPTrONCONCENTRATION RATING DAYS RUN
Additive A1 ptb 0 10
Additive 81 ptb 2 10
Additive A0.5 ptb
O 10
Additive ~0.5 ptb
12~9871
- 29 -
From a review of Table VII, it can be seen
that both Additive A and Additive 3 were effective. It
also can be seen that Additive A and the same total
concentration of a mixture of Additive A and Additive B
were more effective than Additive ~ alone.
EXAMPLE V
A sample comprising 100 ml portion~ of
gasoline containing 10 ptb of HECO and a total of 1 ptb
of Additive A, Additive B or a combination of Additive
A and Additive B wa tested with another typical
gasoline contaminant, refinery process water bottoms
having a pH of 10. A sample containing 90 wt.% of this
fuel and 10 wt.% of the proceqs water bottoms was
utilized. The Multiple Contact Emulsion Te~t described
in Comparative Exzmple V was utilized with one
modification. The sample was shaken at 1 1/2 hour
intervals rather-than 24 hour intervals. Thus, this
procedure is more severe than the test method of
Comparative Example V. The results of this test are
set forth in Table VIII below.
i2~3871
- 30 -
TABLE VIII
MODIFIED EMULSION TEST RESULTS
NUMBER OF
DEMULSIFIER WORST GASOLINE
DESCRIPTIONCONCENTRATION RATING TREATS
Additive A1 ptb 7 10
Additive B1 ptb 2 10
Additive A0.5 ptb
2 10
Additive B0.5 ptb
12~87~
From this table it can be seen that Additive
B and a mixture of Additive A and Additive B were more
effective than Additive A alone.
Demulsifier Additive A was thuq found to be
more effective than Additive B with neutral water,
while Additive B was much more effective than Additive
A when the water wa~ basic. The combination of these
additives is particularly preferred, since it was
highly effective in both neutral and basic conditions.
Where the presently described invention is
used as a gasoline additive, the additive pac~age may
be added to the gasoline at any point after the
gasoline has been refined, i.e., the additive package
can be added at the refinery or in the distribution
system. To assure a relatively constant concentration
of the additive package in the gasoline and to assure
that none of the additives precipitate from the addi-
tive package, diluent solvents typically are combined
with the additive package to produce an additive con-
centrate which is metered into the fuel.
The amine oxide typically has water present
from the manufacturing process. While it is possible
to remove most of the water, removal of the water to
relatively low levels, i.e. a ratio of about 0.02 to
about 0.04 of water to amine oxide, adds complexity to
the manufacturing process. Therefore, the amine oxide
is commercially available as a solution which has the
following composition:
871
Approximate
Additive Concentration, Wt.
HECO 47-49
isopropyl alcohol 45
water 6-8
To provide an additive concentrate which is
pumpable and which does not precipiate even in winter
conditions, the concentrate preferably should have a
cloud point below about -20F and a pour point of
less than -40F.
Typically, the additive package is diluted
in the range of about 1:1 to about 10:1 with diluent
solvent, preferably about 5:1 to facilitate metering
and to provide a concentrate having the desired cloud
and pour points.
COMPARATIV~ EXAMPLE VI
In this test, the additive package was
diluted about 4.9:1 with a diluent which comprised
about 90 wt.~ xylene and 10 wt.~ isopropanol. The
resulting concentrate had the following composition:
Approximate
AdditiveConcentration, Wt.%
Amine Oxide ~.00
Xylene 73.50
isopropyl alcohol 15.84
water 1.00
~emulsifier ~0.83
Demulsifier B0O83
100 .(~0
Twenty-five ml. of this additive concentrate
were mixed with 25 ml. of gasoline and 10 ml. of
refinery water bottoms in an 8 inch centrifuge tube
with a narrow tip to simulate the conditions which
12Qg87~
- 33 -
could occur in the field before the additive
concentrate is completely mixed with the gasoline. An
excess of water was included for illustrative purposes
as set forth below.
The tube was placed in an ultra~onic bath at
room temperature and subjected to ultrasonic fre-
quencies for about five minutes to cause intimate
mixing. After removal from the ultrasonic bath and
centrifugation to facilitate separation, it was noted
that three phases had formed, two organic phases and a
water phase. Formation of two organic phases is not
desirable, since this was found to result in uneven
distribution of the HECO between the layers. In addi-
tion, the second organic layer which ha~ a much higher
HECO concentration, tends to adhere to the surfaces,
resulting in additive los~ and potential contamination
of subsequent hydrocarbon products that might contact
these ~urfaccs.
EXAMPLE VI
.
In this Example, the ~ame additive package
wa-~ used a~ wa~ u~ed in Comparative Example VI. The
additive package again wa~ diluted with about 4.9 parts
solvent. However, in thi~ Example the isopropanol in
the diluent solvent was replaced with an equal weight
of C8 oxo alcohol. The concentrate had the ollowing
composition:
12~871
- 34 -
Approximate
AdditiveConcentration, Wt.
Amine Oxide 8.00
Xylene 73.50
C8 oxo alcohol 8.17
i~opropyl alcohol 7.67
water 1.00
Demulsifier A0.83
Demulsifier B0.83
100.00
Twçnty-five ml. of this additive concentrate
were mixed with 25 rnl. of gasoline and 10 ml. of
refinery water bottoms and intimately mixed in an
ultrasonic bath as described in Comparative Example VI.
After intimate mixing and centrifugation to facilitate
separation, it was noted that only two layers, an
organic layer and a water layer were formed.
~ rom thia Example it can be ceen that the
replacement of at least a portion of the isopropanol by
a higher molecular weight alcohol, preferably a
C4-C12 alcohol, mOrQ preferably an oxo alcohol and
most preferably a Cg oxo alcohol, prevented the
formation of two organic layers. As used herein the
ter~ "oxo alcohol~ refers to one or more branched chain
aliphatic alcohols prepared by the reaction of carbon
monoxide and olefins followed by hydrogenation of the
resulting aldehydes.
A serie~ of teat~ also were run utilizing
different solvents to determine the cloud point of the
resulting additive concentrates. Those test~ generally
were conducted in accordance with ASTM test method
D2500, the disclosure of which is incorporated herein
by reference. These results are presented in Table rx.
871
-- 35 --
o~ Oe E
O o
L~ a.~ ~ o
~ ... .,
_. ~D ~ O V ~ ~ a~ O ~ ~
o ~ ~ ~ v I_I ~ ~ v
:~
O O E O E
_~
C~ U V
,a~
.
0 U~
U~ _~
O E
C~
d
v o o oo o o o o
3 . o o oo o o o o
E~
a~ ~ Oc
E~ 'v ~ a~
~ .~ C ~ o o oo o o o o
O 0 ._,.,.,o oo o o o o o
O E~ ~
O co a~ ~~ a~
O C~ O
~ O
Ll ~ ~t ~D --I ~t't
V ~_1
c t~ ~C o a~o 1~ o
O C O
C O
O ~ O
C.) .)
~ 0 ~0
V ~ Ç
.,. o ~ ,_
C~
o
V ~ I~ o o oC~ o
C ~I _~
~ 0
~4
o
U~
~ ~-o o r~ o '
.. . . .
~ ~ ~ ~ _, ~ r~ u~
X a~
871
~ rom a review of Table IX, it can be seen
that the combination of a solvent system comprising
xylene, isopropyl alcohol and C8 oxo alcohol produces
an additive concentrate which has a cloud point below
about -46~ for the point tested. 8y comparison, use
of a solvent system comprising only xylene and C8 oxo
alcohol produced a system which had acceptable cloud
points only over a very narrow concentration range.
Therefore, the use of a mixed alcohol solvent system is
desirable to produce a concentrate having good low
temperature properties without the tendency to form a
second organic layer.
Multiple Contact Emulsion ~est~ were con-
ducted in a manner similar to that set forth in
Comparative Example V for ga~oline samples. The tests
were run on both unleaded regular grade gasoline and
unleaded premium grade gasoline containing 10 ptb HECO
and 0.5 ptb each of Demulsifiers A and B, to which 10
wt.~ terminal water bottoms having a pH of about 7 and
8, respectively, ha~ been added as previously
described. The samples were shaken for 10 minutes at
180 cycles per minute. The bottle~ then were permitted
to stand for the times indicated and rated. A~ ~hown
by the data in Table X, the replacement of the
i~opropanol by the combination of isopropanol with C8
oxo alcohol did not adver~ely affect the effectiveness
of the demul~ifier package. Thus, a concentrate in-
cluding a solvent system comprising isopropanol and C8
oxo alcohol has acceptable demul~ifying propertie~ and
an improved cloud point relative to a solvent system
comprising C8 oxo alcohol alone, when significant
quantities of water are present. As previously noted,
such a solvent system also does not promote the forma-
tion of multiple organic layer~.
g7~
- 37 -
TABLE X
MULTIPLE CONTACT EMULSION TEST
FuelTime ~Hrs.) Emul~ion Ratinq
Isopropano
Isopropanol + C8 oxo
Alone Alcohol
Unleaded Regular 1 2 2
4 2 2
2g 2 2
Unleaded Premium 1 3 2-3
4 2-3 2-3
24 2 2
