Note: Descriptions are shown in the official language in which they were submitted.
A-39494/MWS/DED
LUBRIC~NT ADDITIVE FOR USE WITH ALCOHOL FUELS
The present invention is directed to an additive formu-
lation for use with conventional automotive lubricants
to produce a lubricant suitable for internal combustion
engines burning alcohol fuels, such as methanol or
ethanol.
Commonly used automotive lubricants are not effective in
alcohol burning engines as evidenced by excessive engine
wear and progressively increasing rates of lubricant
10 -consumption. One reason for this is the large
difference in chemical reactivity of the combustion
products from gasoline and alcohol automotive fuel
systems. In an alcohol fuel system, a number of lubri-
cant degradation reactions occur which are not encoun-
15 -tered in the gasoline fuel system. These chemical
reactions cause the increased corrosiveness of alcohol
fuels. For instance, methanol readily oxidizes to form
formaldehyde and formic acid. This reaction is
represented by Equation 1.
- CH30H > HCHO > HCOOH (~)
(methanol) (formaldehyde) (formic acid)
Most vehicles using methanol fuel suffer from excessive
upper-cylinder corrosion and bearing wear resulting from
the formic acid produced by methanoi combustion. Formic
acid reacts with the conventional automotive lubricant's
,~;
.3
--2--
organic amine additives which function as antioxidants,
corrosion inhibitors, and anti-wear ag~nts. The amine
additives neutralize the formic acid. However, the
conventional additives seem unable to adequately neutra-
lize the amount of formic acid formed in methanolcombustion. These reactions are represented in Equa-
tions 2 and 3.
RNH2 + 2HCOoH neutralization > RNH2-2HCOOH (2)
(primary (formic
amine) acid)
R2NH + HCOOH neutralization > R2NH-HCOOH (3)
(secondary (formic
amine) acid)
Formaldehyde is highly reactive with phenolic and glycol
additives. Formaldehyde reacts with the phenols which
are used as antioxidants and with the polymers contain-
ing hydroxyl groups which are used as ashless dispers-
ants. These reactions take place under acidic condi-
tions and increase as the organic amine additives are
depleted by reaction with formic acid. These formalde-
hyde reactions, represented by Equation (4), contribute
significantly to oil de~radation in a methanol fuel
system.
ROH + HCHo aCid Catalyzed ~ ROCH2OR (4)
aldol condensation
(phenol (formaldehyde)
or glycol)
There is a need for a lubricant additive which minimizes
the oxidation of methanol to formaldehyde and formic
acid and m;n;m;zes excessive formaldehyde and formic
acid reactions in order to prolong the life of lubricant
~Z~;~6~.3
additives which are depleted rapidly by reaction with
formaldehyde and formic acid. Similarly, there is a
need for a lubricant additive which minimizes the
oxidation of ethanol to acetaldehyde and acetic acid and
S minimizes excessive reactions of those components.
Another significant problem in an alcohol fuel system is
that zinc dialkyldithiophosphate, a major multi-
functional additive in most conventional lubricants,
readily transesterifies and thereby loses many of its
anti-wear properties. The transesterification reaction
involves the interchange of an alcohol alkyl group, such
as methanol or ethanol, with an existing ester, such as
zinc dialkyldithiophosphate, to form a new ester. A
transesterification reaction is represented in Equation
5.
RCOOR' + CH OH acid catalYZed RCOOCH3 + R'OH (5)
(existing (methanol) (new ester)
ester)
The transesterification reaction is acid catalyzed and
therefore occurs after the amine base additives in the
lubricant are depleted by reaction with aldehydes and
acids formed in the combustion process. Transester-
ification is not a major mechanism of oil degradation in
hydrocarbon fuel systems but is a primary mechanism of
oil degradation in methanol and other alcohol fuel
systems. For instance, when methanol and ethanol are
blended with gasoline, the magnitude of the transester-
ification reaction is proportional to the amount of
alcohol in the mixture.
Another cause of increased corrosiveness in an alcohol
burning engine is the increased solubility of carbon
~ 2~6~3
dioxide in the alcohol. For instance, carbon dioxide is
much more soluble in methanol than in water. Both water
and methanol are usually present in the cooler parts of
the crank case as products of combustion. The water
reacts with the fuel combustion products, such as SO3,
NO2, and CO2 to form the corresponding acids, sulfuric
acid, nitric acid, and carbonic acid, as represented in
Equations 6, 7, and 8.
SO3 + H2O ~ H2SO4 (6)
(sulfuric acid)
NO2 + H2O ' 3 (7)
(nitric acid)
C2 + H2O ~ H2CO3 (8)
(carbonic acid)
These acids reacting with metals in the engine are one
of the major causes of corrosion in an internal com-
bustion engine~ The lubricants commonly used in a
hydrocarbon fuel system effectively neutralize these
acids with basic additives such as organic amines and
alkaline metal compounds. However, carbonic acid levels
are significantly higher in a methanol or other alcohol
fuel system than in a gasoline fuel system due to the
increased solubility of CO2 in alcohols. The same may
be true of nitric acid formed from NO2 combustion
products. Absorption of carbon dioxide appears to be an
important reason for the unexpectedly high corrosiveness
of alcohol fuels.
Lubricant analysis indicates that corrosion inhibitors
composed of sulfonates, naphthenates or other alkaline
metals are extensively depleted by reaction with
31 ;2~ .3
carbonic acid, resultiny in the precipitation of
insoluble carbonates of the alkaline metals. The
precipitation reaction is represented in Equations 9 and
10 .
RS03Ba ~ H2C03 > BaC03 ~ RCOOH (g)
RS03Ca + H2C03 > CaC03 + ~S03H (10)
This precipitation reaction competes with the neutrali-
zation of carbonic acid by organic amines. Although the
neutralization is faster and more likely to occur, the
reaction with alkaline metal salts increases as the
organic amines are depleted. Thus, there is a need for
a lubricant additive wherein depletion of the organic
amine additives due to neutralization of formic acid or
acetic acid and carbonic acid occurs less rapidly, thus
decreasing the likelihood that alkaline metal salts will
be depleted by the precipitation reactions represented
in Equations 9 and 10.
It is a general ob]ect of the present invention to
provide a lubricant additive for use in an alcohol fuel
burning internal combustion engine which provides
protection against corrosive and engine wear effects
caused by alcohol.
It is another object of the present invention to provide
a lubricant additive with increased capacity to neu-
tralize acids.
It is a further object of the present invention to
provide a lubricant additive comprising an anti-wear
agent which is not degraded by methanol or ethanol.
.,,
--6--
The present invention provides a lubricant additive
which can be added to conventional automotive lubricants
to produce a lubricant suitable for use in a methanol or
ethanol burning enginel comprising a major amount of a
polyalkylene glycol of an alkene having 2 to 3 carbons,
and minor amounts of an aromatic primary amine, an
aromatic secondary amine, and a phosphoric acid ester.
Preferred amounts of the compounds contained in the
lubricant additive of the present invention are about
93-98.5 wt.% of a polyalkylene glycol, about 0.5-2.0
wt.% of an aromatic primary amine, about 0.5-2.0 wt.% of
an aromatic secondary amine, and about 0.5~2.0 wt.~ of a
phosphoric acid ester.
The lubricant additive of the present invention com-
prises a polyalkylene glycol of an alkene having 1 to 2carbons, such as polypropylene glycol, polyisopropylene
glycol, or polyethylene glycol; an aromatic primary
amine, such as ortho-, meta-, or para- phenylenediamine,
ortho-, meta- or para- toluidine, aniline, naphthyl-
amine, benzylamine, tolulenediamine, or naphthalene-
diamine; an aromatic secondary amine, such as N-phenyl-
2-naphthylamine, phenyl-~-naphthylamine, phenyl-~-
naphthlyamine, tolylnaphthylamine, diphenylamine,
ditolylamine, phenyltolylamine, 4,4'-diaminodiphenyl-
amine, or N-methylaniline; and a phosphoric acid ester,
such as ortho-, meta-, or para- tricresylphosphate,
dibutylphenylphosphate, tributylphosphate, tri-2-ethyl-
hexylphosphate, trioctylphosphate, diphenyl ortho
phosphonate, dicresyl ortho phosphonate, trilauryl ortho
phosphonate, tristearyl ortho phosphonate.
A preferred polyalkylene glycol is polypropylene glycol
and a preerred polypropylene glycol is polypropylene
glycol 2000. A preerred aromatic primary amine is
26~.~
--7--
ortho-phenylenediamine; a preferred aromatic secondary
amine is N-phenyl-2-naphthylamine, and a preferred
phosphoric acid ester is ortho-tricrecylphosphate.
Preferably, the lubricant additive of the present
invention contains about 93 to 98.5 wt. % of a poly-
alkylene glycol of an alkene having 1 to 2 carbons,
about 0.5 to 2.0 wt. % of an aromatic primary amine,
about 0.5 to 2.0 wt. ~ of an aromatic secondary amine,
and about 0.5 to 2.0 wt. ~ of a phosphoric acid ester.
A preferred composition of the present invention com-
prises about 93 to 98.5 wt. % polypropylene glycol 2000,
about 0.5 to 2.0 wt. % of ortho-phenylene-diamine, about
0.5 to 2.0 wt. % of N-phenyl-2-naphthylamine, and about
0.5 to 2.0 wt. % of ortho-tricrecylphosphate.
All of the above compounds are commercially available.
The lubricant additive of the present invention is made
by blending together each of the above compounds. The
lubricant additive of the present invention can be used
by adding approximately one pint of the lubricant
additive to a 5 quart oil change. The lubricant
additive of the present invention will provide effective
protection against corrosive and engine wear effects
caused by methanol or ethanol for oil change intervals
of more than ~000 miles and in some cases up to 6000
miles.
The polyalkylene glycol, preferably polypropylene
glycol, functions as a methanol or ethanol solubilizer,
a non-ash dispersant and a scavenger for aldehydes. A
solubilizer of this type is requixed to dissolve the
large amounts of methanol or ethanol introduced into the
lubricant prior to combustion. The polyalkylene glycol
.3
--8--
solubilizes the methanol or ethanol thereby preventing
dry spots on the upper cylinder and bearing surfaces.
In the absence of glycol, methanol or ethanol is
insoluble in hydrocaxbon lubricants and dry spots can
occur. In addition, a polyalkylene glycol contains
hydroxyl groups which react with the aldehydes formed by
the oxidation of methanol or ethanol. The reaction
product of a polyalkylene glycol and formaldehyde or
acetaldehyde is also a good solvent for methanol or
ethanol and continues to function as a methanol or
ethanol solubilizer.
The aromatic primary amine, preferably ortho-phenylene-
diamine, functions primarily as a base number additive
to neutralize formic or acetic and carbonic acids formed
by the oxidation of methanol or ethanol and by the
reaction of water and carbon dioxide, respectively.
The aromatic secondary amine, preferably N-phenyl-2-
naphthylamine, also serves to neutralize formic or
acetic and carbonic acids however, its primary function
is as an antioxidant. It m;n jm; zes the oxidation of
methanol or ethanol to their respective aldehydes and
acids.
The presence of larger amounts (about 0.5 to 2.0 wt. %)
of organic amines in the present invention, as compared
to the amount generally contained in conventional
lubricant additives (about 0.25 wt. ~), minimizes
depletion of alkaline metal salts, such as naphthenates
and sulfonates. The alkaline metals are depleted when
they react with carbonic acid to form insoluble car-
bonates, competing with the neutralization of carbonicacid. The neutralization reaction is faster and more
likely to occur, but the precipitation reaction becomes
~26J~.3
a problem when the organic amines become depleted. With
more organic amines present, more carbonic acid is
neutralized and there is less carbonic acid available to
react with the alkaline metals.
The phosphoric acid ester, preferably ortho-tricrecyl-
phosphate, functions as an anti-wear agent and when used
with methanol or ethanol fuel it is superior to the
conventional anti-wear agent, zinc dialkyldithiophos-
phate. Zinc dialkyldithiophosphate is almost universal-
ly used in automotive lubricants for gasoline burningengines but loses its anti-wear properties rapidly in a
methanol or ethanol burning engines because it readily
transesterifies with the alcohols.
A lubricant additive can be evaluated based on the
amounts of wear elements, such as iron, lead, and
copper, detected in an oil sample by spectrochemical
analysis after the engine has been driven a certain
number of miles after an oil change. These metals or
wear elements show up in the lubricant as a result of
excessive corrosion of or failure of certain engine
components made of that metal as well as normal mechani-
cal wear.
Table 1 sets forth criteria for evaluation of lubricant
wear element data. The primary and secondary source in
the engine of each wear element is given as well as the
average amount in ppm's of each weax element which would
be found in the oil at the "break-in" point and at the
"post break~in" point. Engine wear levels during the
break-in period tend to be relatively high. After the
engine has been broken in, the wear levels reach a
plateau, remaining stable for about 50,000 miles,
$~ ~. 3
--10 ~
depending on the particular vehicle and degree of
maintenance. The "break~in" point for an average engine
is generally in the 0 to 10,000 mile range. The evalua-
tion criteria found in Table 1 will be used to evaluate
the data set forth in Examples 1 through 5.
In Examples 1 and 3, data is also included regarding the
percent volume of diluted fuel, the percent volume of
total solids, the percent volume of water, viscosity,
and base number of the oil sample tested.
The average amount of oil dilution caused by blow-by is
about 3% for both alcohol and gasGline fuels. The
amount of dilution is significantly greater during cold
weather because of increased condensakion. A sticking
choke, improper ignition, low operating temperatures and
blow-by are the factors most commonly contributing to
fuel dilution. Dilution in excess of 3% decreases the
viscosity of oil, causing increased engine wear.
Solids in engine oil usually consist of soot, metal
salts, road dirt, sludge, and oxidized oil caused by
undesirable engine operating conditions such as poor
ignition, inefficient air filters, and blow-by. These
solids can cause engine malfunction if they prevent oil
from getting to critical engine and bearing surfaces. A
total solids value greater than 3~ indicates a serious
problem.
Water contents in excess of .1% are generally considered
excessive in vehicles using gasoline fuels. Because of
the hygroscopic properties of alcohols, vehicles using
this fuel often have water contents that exceed 0.5%.
High water contents accelerate both organic sludge
formation and corrosion reactions. High values can
3~2Q;~
result from atmospheric water mixing with the alcohols,
leaks from the cooling system, low operating tempera
tures or an inoperative pollution control valve system.
An automotive lubxicant with normal viscosity has the
same numerical value as the Society of Automotive
Engineers (SAE) grade of the oil being used. High
viscosity values generally indicate oil degradation
caused by infrequent oil changes. Low viscosity values
are generally caused by fuel dilution. ~iscosity values
are not directly proportional to engine wear, a change
of 10 units in either direction can indicate significant
lubricant degradation.
Base number is a measure of the oil detergent action and
its ability to inhibit corrosion. New automotive oils
commonly have a base number of 4 to 5. For any oil, a
reading of 1 or less indicates a dangerous depletion of
additive reserves. A base number of 2 is generally
considered to provide an adequate margin of protection
in a gasoline burning engine.
-12-
TABLE 1
Criteria for Evaluation of Lubricant Wear Element Data
Evaluation Critexia, ppm Source
Break-In Post Break-In
Wear Element Average Excessive Average Excessive Primary Secondary
Iron tFe)200-400400 10-100 200 cylinder block,
wall crank-
shaft,
wrist pins,
rings,
valves,
oil pump,
fuel tank
Molybdenum 2-4 5 0-2 3 cylinder block,
(Mo) wall crank-
shaft,
wrist pins,
rings,
valves,
oil pump,
fuel tank
Lead (~b)100-300300 5-100 150 bearings flashing,
TEL in fuel
Copper (Cu) 50-150 150 5- 75 100 bearings bushings,
cam,
valve train,
thrust
washers,
oil pump
Tin (Sn)20- 50 50 1- 10 15 bearings flashing
Chromium (Cr) 2- 10 10 1- 5 5 rings crankshaft,
exhaust
Nickel (Ni) 3- 5 5 1- 2 4 valves, rings
crankshaft
Aluminum (Al)30-100 100 1- 15 30 pi.stons,
alumin~n
blocks
~12~ .3
-13-
Example 1
An oil sample comprising a conventional automotive
lubricant and 10 wt. % of the lubricant additive of the
present invention comprising about 97 to 98.5 wt. %
polypropylene glycol 2000, about 0.5 to 1.0 wt. % of
ortho-phenylenediamine, about 0.5 to 1.0 wt. % of
N-phenyl-2-naphthylamine, and about 0.5 to 1.0 wt. % of
ortho-tricrecylphosphate was taken from the crank case
in methanol fueled engine A which had been driven the
equivalent of 12,459 miles with an oil change
approximately 2,000 miles prior thereto. The sample
contained less than 0.5% volume of diluted fuel, 1.5%
volume total solids, less than 0.05% volume water, and
had a total base number of 3.70. The oil had an initial
viscosity of SAE 30 and the viscosity remained unchang~d
during testing.
The base number of 3.70 was well above the adequate base
number of 2, indicating that the aromatic primary and
secondary amines had not been depleted and were still
available for neutralizing formic acid and carbonic acid
and preventing oxidation of methanol to formaldehyde and
formic acid.
The percent volume of diluted fuel and percent volume
total solids were well below the average 3% value
indicating no increase in engine wear. The percent
volume water was well below the 0.1% value which is
collsidered to be excessive and thus indicates no corro-
sion problems due to water content. The viscosity of
the oil sample was normal.
Spectrochemical analysis revealed that the following
amounts of wear elements were present in the oil sample:
6 ~.~
-14-
36 ppm iron; 66 ppm lead; 107 ppm copper; 2 ppm chromi-
um; ~ ppm aluminum; 2 ppm nickel; and 12 ppm tin. The
engine had been driven the equivalent of 12,459 miles
which is just over "break-in" mileage of about 10,000
miles~ Thus, the sample will be evaluated using both
"break-in" and "post break-in" criteria. It should be
noted, however, that the mileage is closer to "break-in"
mileage and thus the "break-in" criteria are a more
accurate measure of the amount of engine wear.
Referring to Table 1, the iron, lead, tin, nickel and
aluminum content in the sample was less than the average
content of these wear elements at "break-in" mileage.
The copper content was within the average range at
"break-in" mileage. The chromium content was at the low
end of the average range at "break-in" mileage. At
"post break-in" mileage, the lead, chromium, nickel, and
aluminum contents were within the average range. The
iron content was at the lower end of the average range.
The data provided by Example 1 illustrates that the
lubricant additive of the present invention is effective
in a methanol burning engine at or near break-in mile-
age.
Example 2
~n oil sample comprising the c~nventional automotive
lubricant and 10 wt. % of the lubricant additive used in
Example 1 was taken from the crank case of methanol
fueled engine A whish had been driven the equivalent of
14,034 miles with an oil change at approximately 3,575
miles prior thereto. It had a total base number of
3.08. The base number of 3.08 was well above the
adequate base number of 2, indicating that the aromatic
.3
-15-
primary and secondary amines have not been depleted and
are still available for neutralizing the acids and
preventing oxidation of methanol.
Spectrochemical analysis revealed that the following
amount of wear elements were present in the oil sample:
52 ppm iron; 64 ppm lead; 102 ppm copper; 1 ppm chro~
mium; 5 ppm aluminum; 1 ppm nickel; and 10 ppm tin.
Since the engine had been driven an equivalent 14,034
miles, the post break-in evaluation criteria shown in
Table 1 were applied.
Referring to Table 1, the iron, lead, chromium, alumi-
num, nickel, and tin content in the sample were all
within the average range at post break-in mileage.
The data in Examples 1 and 2, including the base
numbers, indicate that the lubricant additive of the
present invention will be effective at 4,000 mile oil
change intervals, and should be effective at longer oil
chanye intervals of up to 6,000 miles. The small wear
element levels in Examples 1 and 2 also indicate that
engine A was in good condition.
Example 3
An oil sample comprising a conventional automotive
lubricant and 10 wt. % of the lubricant additive used in
Example 1 was taken from the crank case of methanol
fueled engine B which had been driven the equivalent of
31,724 miles with an oil change at approximately 2,000
miles prior thereto. The oil sample contained less than
0.5% volume diluted fuel, about 5.0% volume total
solids, less khan 0.05~ volume water, and had a total
2~i~.3
~16-
base number of 2.3~. The oil had an initial viscosity
of SAE 30 which remained unchanged during testing.
The base number was greater than the adequate base
number of 2 indicating that there were substantial
amounts of primary and secondary aromatic amines avail-
able for neutralizing acids and preventing oxidation of
methanol.
The percent volume diluted fuel and percent volume total
solids were far below the average 3% value and thus
indicated no increase in engine wear. The percent
volume water was also far below the 0.1% value
considered excessive and thus also indicates no serious
corrosion problem due to the presence of water. The
total solids value was greater than the average value of
3% indicating the presence of more than an average
amount of solids. The viscosity of the oil sample was
normal.
The spectrochemical data shows that the following wear
elements were present in these amounts: 47 ppm iron; 44
ppm lead; ~3 ppm copper; 17 ppm chromium; 4 ppm alumi-
num; 2 ppm nickel; and 14 ppm tin~ The wear element
content of iron, lead, aluminum, and nickel was within
the average range in Table 1 for post break-in mileage.
Thus, Example 3 also illustrates that the lubricant
additive of the present invention is effective in a
methanol burning engine at "post break-in" mileage.
Example 4
An oil sample comprising a conventional automotive
lubricant and the 10 wt. ~ of lubricant additive used in
3~.~.3
Example 1 was taken from the crank case of methanol
fueled engine B which had been driven the equivalent of
33,307 miles with an oil change at approximately 3,583
miles prior thereto. The oil sample had a total base
number of 2.46. The base number is greater than the
adequate base number of 2 and thus, indicates that there
are substantial amounts of primary and secondary
aromatic amines available for neutralizing acids and
preventing oxidation of methanol.
Spectrochemical data shows that the following wear
elements were present in these amounts: 85 ppm iron; 63
ppm lead; 76 ppm copper; 16 ppm chromium; 3 ppm alumi-
num; 1 ppm nickel; and 11 ppm tin. The wear element
content of iron, lead, aluminum and nickel was within
the average range shown in Table 1 for post break-in
mileage. The copper content was 1 ppm higher than the
average amount but much less than 100 ppm which is
considered to be excessive. Thus, Example 4 illustrates
that the lubricant additive of the present invention is
effective in a methanol burning engine at post break-in
mileage, and that it will be effective at 4,000 mile oil
change intervals.
Example 5
An oil sample comprising a conventional automotive
lubricant and 10 wt. % of the lubricant additive used in
Example 1 was taken from the crank case of methanol
fueled engine B which has been driven the equivalent of
34,815 miles with an oil change at approximately 5,091
miles prior thereto. The oil sample had a total base
number of 1.68. Although the base number is slightly
less than the base number of 2, it still indicates that
there are adequate amounts of primary and secondary
~2~ .3
-18-
aromatic amines available for neutralizing acids and
preventing oxidation of methanol.
Spectrochemical data shows that the following wear
elements were present in these amounts: 77 ppm iron;
160 ppm lead; 67 ppm copper; 10 ppm chromium; 0 ppm
aluminum; 1 ppm nickel; and 0 ppm tin. The wear element
content of iron, copper and nickel were within the
average range at post break-in mileage as shown in Table
1. Less than the average amounts of aluminum and tin
were found in the sample. Thus, Example 5 illustrates
that the lubricant additive of the present invention is
effective in a methanol burning engine at post break-in
mileage at 5,000 mile oil change intervals.
Engine B of Examples 3, 4 and 5 was in poor condition at
the beginning of testing as evidenced by the high
chromium levels 2,000 miles after the oil change. The
wear element content levels and the base numbers in
Examples 3, 4 and 5 did not change significantly during
the testing period indicating that the lubricant
additive of the present invention is effective even in
engines in poor condition.
Example 6
Oil samples were taken from a methanol burning
automotive engine prior to running the engine and 20
hours after continuous running of the engine in three
test runs. In the first test run, the oil in the engine
contained no lubricant additive. In the second and
third test runs, the oil in the engine contained 10 wt.
% of the lubricant additive of the present invention.
The followirlg wear element data was obtained by
spectrochemical analysis.
Test RunTest Hour PPM of Wear Element
Fe Pb Cu Cr Al Ni Sn
1 0 4 10 115 1 2 2 7
125 13 120 4 8 3 11
2 0 3 10 115 1 2 1 3
14 10 94 1 2 1 5
3 0 3 10 115 2 2 1 6
21 10 110 3 2 1 6
Comparing Test Run 1 to Test Runs 2 and 3, the wear
element content indicates that without the lubricant
additive of the present invention, a methanol burning
engine experiences a significant increase in engine
wear. The increase is especially evident from the
content of iron. In Test Run 1, after 20 hours of
continuous running, 125 ppm of iron was present, whereas
in Test Runs 2 and 3 after 20 hours of continuous
running only 14 and 21 ppm of iron, respectively, was
present.
In Test Run 1 in general the amount of all wear elements
increased after 20 hours of engine running;, whereas in
Test Run 2 the lead, chromium, aluminum and nickel
content remained the same, while the copper content
decreased and the tin content increased by only 2 ppm.
In Test Run 3, the lead, aluminum, nickel and tin
content remained the same, while the copper content
decreased and the chromium content increased by 1 ppm.
.3
-20-
Thus, it can be concluded that a methanol burning engine
using the lubxicant additive of the present invention
will experience much less engine wear than without the
lubricant additive of the present invention.
--21--
WEIAT I S CLAIMED I S:
1. A lubricant additive for use with alcohol fuels,
comprising a major amount of a polyalkylene glycol of an
alkene having 2 to 3 carbons, and minor amounts of an
aromatic primary amine, an aromatic secondary amine and
a phosphoric acid ester.
2. A lubricant additive for use with alcohol fuels,
comprising about 93.0 to 98.5 wt ~ of a polypropylene
glycol, about 0.5 to 2.0 wt % of an aromatic primary
amine, about 0.5 to 2.0 wt ~ of an aromatic secondary
amine, and about 0.5 to 2.0 wt % of a phosphoric acid
ester.
3. A lubricant additive according to Claim 1 wherein
said polyalky]ene glycol of an alkene having 2 to 3
carbons is polypropylene glycol 2000.
~. A lubricant additive according to Claim 2 wherein
said polypropylene glycol is polypropylene glycol 2000.
5. A lubricant additive according to Claim 1 or 2
wherein said aromatic primary amine is ortho-phenylene-
diamine.
6. A lubricant additive according to Claim 1 or 2wherein said secondary aromatic amine is N-phenyl-2-
naphthylamine.
7. A lubricant additive according to Claim 1 or 2
wherein said phosphoric acid ester is ortho-tricrecyl-
phosphate.
~,2~ .3
-22-
8~ A lubricant additive according to Claim 2 wherein
said polypropylene glycol content is about 97.0 to 98.5
wt. %, said aromatic primary amine content is about 0.5
to 1.0 wt. %, said aromatic secondary amine content is
about 0.5 to 1.0 wt. % and said phosphoric acid ester
content is about 0.5 to 1.0 wt. %.
9. A lubricant additive for use with alcohol fuels,
comprising about 97-98.5 wt % of polypropylene glycol
2000, about 0.5-1.0 wt % ortho-phenylenediamine, about
0.5-1.0 wt % of N-phenyl-2-naphthylamine, and about
0.5-1.0 wt % of ortho-tricrecylphosphate.
Smart & B~oar
Ott~lwa. Canada ~k
Patent ~q~nts
ABSTRACT
A lubxicant additive for use with alcohol fuels is
provided comprising a major amount of a polyalkylene
glycol of an alkene having 2 to 3 carbons, and minor
amounts of an aromatic primary amine, an aromatic
secondary amine and a phosphoric acid ester. A pre-
ferred composition comprises about 93-98.5 wt % of a
polypropylene glycol, about 0.5-2.0 wt % of an aromatic
primary amine, about 0.5-2.0 wt % of an aromatic secon-
dary amine, and about 0.5-2.0 wt % of a phosphoric acid
ester. A preferred polypropylene glycol is polypropy-
lene glycol 2000; a preferred aromatic primary amine is
ortho-phenylenediamine; a preferred aromatic secondary
amine is N-phenyl-2-naphthylamine; and a preferred
phosphoric acid ester is ortho-tricrecylphosphate.
