Description
Motor Fuel Additive Composition and Method for Preparation Thereof
Background of the Invention
This invention relates to a motor fuel additive composition and a method of preparing such an
additive. More particularly, this invention relates to a motor fuel additive composition comprising:
(a) a detergent component selected from the group consisting of (i) at least one nonionic compound having a molecular weight in the range of 200-1500, (ii) a reaction product component which is the
reaction product of a substituted hydrocarbon and an amino compound, and (iii) a polybutylamine or
polyisobutylamine; and (b) a fuel conditioner
component comprising (i) a polar oxygenated
hydrocarbon compound, and (ii) an oxygenated
compatibilizing agent. This invention also relates to a method of preparing a motor fuel additive which comprises mixing the above-described reaction product and fuel conditioner components.
Incomplete combustion of hydrocarbonaceous motor fuels in an internal combustion engine is a common problem which generally results in the formation and accumulation of carbon and other deposits in various places, including the fuel inlet system. Significant efforts have previously been undertaken to develop fuel additives to reduce or inhibit deposit formation in the engine fuel inlet system. Early so called "first generation" additives directed primarily to cleaning carburetors and injectors include low molecular weight amine derivatives such as fatty amines, amides, amido amines and imidazolines. Later developed so-called "second generation" additives, directed to cleaning inlet valves as well as
carburetors and injectors, have been based primarily on polyolefinic structures, typically polyisobutenes and their derivatives. For example, the use of polybutene succinimides as fuel additives has been disclosed in U.S. Pat. No. 3,443,918 (Kautsky et al.) and U.S. Pat. No. 3,172,892 (LeSeur et al.); the use of polybutene amines as fuel additives has been disclosed in U.S. Pat. No. 3,438,757 (Honnen et al.).
For effective deposit control, it has been customary to use such additives in conjunction with petroleum based or synthetic carrier oils. Petroleum based oils useful in this respect include naphthenic and paraffinic base stock oils of relatively high viscosity, including so-called Solvent Neutral Oils such as SNO-500 and SNO-600, as well as so-called top cylinder oils and the like. Synthetic oils which have been employed include low molecular weight
polypropylenes and polyisobutylenes, as well as polyalkyleneoxides.
Although the above-described additives have been found effective in reducing deposits in the fuel intake system, the increased use of these additives, particularly the second generation additives, in motor fuels has been found to have led to an increase in combustion chamber deposit formation. The presence of deposits in the combustion chamber seriously reduces engine operating efficiency for several reasons.
First, deposit accumulation within the combustion chamber inhibits heat transfer between the chamber and the engine cooling system. This leads to higher temperatures within the combustion chamber, resulting in increases in the end gas temperature of the
incoming charge. Consequently, end gas auto-ignition occurs, which causes engine knock. In addition, the accumulation of deposits within the combustion chamber reduces the volume of the combustion zone, causing a higher than design compression ratio in the engine. This, in turn, also results in serious engine
knocking. A knocking engine does not effectively utilize the energy of combustion. Moreover, a
prolonged period of engine knocking will cause stress fatigue and wear in vital parts of the engine. The above-described phenomenon is characteristic of gasoline powered engines. It is usually overcome by employing a higher octane gasoline for powering the engine, and hence has become known as engine octane requirement increase (ORI) phenomenon.
In view of the foregoing, it would clearly be advantageous to employ an additive in motor fuel compositions which reduces deposits in engine fuel intake systems and also avoids the formation of deposits in engine combustion chambers, thereby reducing or at least modifying the composition of deposits which tend to cause engine ORI. It is an object of this invention to provide a motor fuel additive which is useful in preventing both fuel intake system deposit formation and combustion chamber deposit formation. It is a feature of this invention that the additive comprises a detergent component and a fuel conditioner component which synergistically interact to reduce both fuel intake system and
combustion chamber deposit formation. It is an advantage of this invention that it both reduces deposit formation in engine fuel intake systems and ORI associated with combustion chamber deposit
formation.
It is another object of this invention to provide a method for preparing a motor fuel additive which reduces deposits in engine fuel intake systems and also reduces the formation of deposits in engine combustion chambers, thereby reducing engine ORI. It is another feature of this invention that such an additive is prepared by mixing a detergent component and a fuel conditioner component which synergistically interact to reduce both fuel intake system deposit
formation and ORI associated with combustion chamber deposit formation.
Summary of the Invention
The motor fuel additive composition of this invention comprises a mixture of:
(a) from 5-50 weight percent, based upon the total weight of the additive, of a detergent component selected from the group consisting of
(i) at least one nonionic compound having a molecular weight in the range of 200-1500,
(ii) a reaction product of:
(A) a substituted hydrocarbon of the formula
R1 - X (I) wherein R 1 is a hydrocarbyl radical having a
molecular weight in the range of 150-10,000, and X is selected from the group consisting of halogens, succinic anhydride and succinic dibasic acid, and
(B) an amino compound of the formula
H - (NH - (A)m)n - Y - R2 (II) wherein Y is 0 or NR5, R5 being H or a hydrocarbyl radical having 1-30 carbon atoms; A is a straight chain or branched chain alkylene radical having 1-30 carbon atoms; m has a value in the range of 1-15; n has a value in the range of 0-6; and R2 is selected from the group consisting of H, a hydrocarbyl radical having a molecular weight in the range of 15-10,000, and a homopolymeric or heteropolymeric polyoxyalkylene radical of the formula
R3 - ((Q)a(T)b(Z)c)d- (Hi) wherein R3 is H or a hydrocarbyl radical having 1-30 carbon atoms, Q, T, and Z are polyoxyalkylene moieties having 1-6 carbon atoms, a, b and c each have values ranging from 0-30, and d has a value in the range of 1-50, and
(iii) a polybutylamine or
polyisobutylamine of the formula
where R11 is a polybutyl or polyisobutyl radical derived from isobutene and up to 20% by weight of n- butene and R12 and R13 are identical or different and are each hydrogen, an aliphatic or aromatic
hydrocarbon, a primary or secondary, aromatic or aliphatic aminoalkylene radical or polyaminoalkylene radical, a polyoxyalkylene radical or a hetaryl or heterocyclyl radical, or, together with the nitrogen atom to which they are bonded, form a ring in which further hetero atoms may be present; and
(b) a fuel conditioner component comprising:
(i) from 2-50 weight percent, based upon the total weight of the additive, of a polar oxygenated hydrocarbon having an average molecular weight in the range of 250-500, an acid number in the range of 25-175, and a saponification number in the range of about 30-250, and
(ii) from 2-50 weight percent, based upon the total of the additive, of an oxygenated compatibilizing agent having a solubility parameter in the range of about 8.8-11.5 and moderate to strong hydrogen-bonding capacity.
The fuel conditioner component may additionally comprise a hydrophilic separant such as a glycol monoether, and an aromatic hydrocarbon such as xylene or a xylene. The additive composition may
additionally comprise a carrier oil or fluidizer.
This invention is also directed to a method of preparing the motor fuel additive of this invention, which comprises mixing the detergent and fuel
conditioner components to obtain the additive. The motor fuel additive of this invention is advantageous in that the detergent and fuel conditioner components
synergistically interact when employed in a fuel composition to reduce both fuel intake system deposit formation, thereby improving engine performance, and combustion chamber deposit formation, thereby reducing engine ORI.
Brief Description of the Drawings
Figure 1 depicts the results of engine test stand experiments for various motor fuel compositions, including motor fuel compositions containing the additive of this invention.
Figure 2 depicts the results of the engine test stand experiments set forth in Figure 1 for various motor fuel compositions, including motor fuel
compositions containing the additive of this
invention, as a plot of Combustion Chamber Rating vs. Intake Valve Deposits (mg).
Description of the Preferred Embodiments
This invention is directed to a motor fuel additive and to a method for the preparation thereof. The additive comprises: (a) a detergent component which is selected from the group consisting of (i) at least one nonionic compound having a molecular weight in the range of 200-1500, (ii) the reaction product of a substituted hydrocarbon and an amino compound, (iii) a polybutylamine or polyisobutylamine; and (b) a fuel conditioner component comprising a polar
oxygenated hydrocarbon compound and an oxygenated compatibilizing agent.
The nonionic compound detergent component, if employed, is preferably an alkylaryl ether alcohol or alkylaryl polyether alcohol having a molecular weight in the range of 200-1500. In a particularly preferred embodiment, the nonionic detergent compound is an octylphenyl polyether alcohol or nonylphenyl polyether alcohol containing 1-10 ethylene oxide moieties.
If the reaction product detergent component is employed, the substituted hydrocarbon reactant used to prepare the reaction product is of the formula
R1 - X (I) wherein R, is a hydrocarbyl radical having a molecular weight in the range of 150-10,000, preferably a polyalkylene radical having a molecular weight in the range of 400-5000 , most preferably a polyalkylene radical having a molecular weight in the range of 600-1500, and X is selected from the group consisting of halogens, preferably chlorine, succinic anhydride and succinic dibasic acid. In one preferred
embodiment, R1 -X is a polyisobutenyl succinic
anhydride. In another preferred embodiment, R1 -X is a chloropolyisobutylene.
The amino compound reactant used to prepared the reaction product is of the formula
H - (NH - (A)m)n - Y - R2 (II) wherein Y is 0 or NR5, where R5 is H or a hydrocarbyl radical having 1-30, preferably 1-22 carbon atoms, A is a straight chain or branched chain alkylene radical having 1-30, preferably 1-15 carbon atoms, m has a value in the range of 1-15, preferably 1-12, n has a value in the range of 0-6, preferably 0-5, and R2 is selected from the group consisting of H, a hydrocarbyl radical having a molecular weight in the range of 15- 10,000, preferably 15-2000, and a homopolymeric or heteropolymeric polyoxyalkylene radical of the formula
R3 - ((Q)a(T)b(Z)c)d- (III) wherein R3 is H or a hydrocarbyl radical having 1-30, preferably 1-22 carbon atoms, Q, T, and Z are
polyoxyalkylene moieties having 1-6 carbon atoms, a, b, and c each have values ranging from 0-30, and d has a value in the range of 1-50, preferably 1-25.
Various preferred embodiments of the amino compound reactant of formula (II) are given in Table 1 below:
In another preferred embodiment, R
2 is the above-described homopolymeric or heteropolymeric polyoxyalkylene radical of formula (III). As used in this description and in the appended claims, the terms homopolymeric and heteropolymeric refer to
polyoxyalkylene compounds, which in the case of homopolymeric compounds contain one recurring
polyoxyalkylene moiety, and in the case of
heteropolymeric compounds contain more than one recurring polyoxyalkylene moiety, typically having 1-6 carbon atoms, such as ethylene oxide (EO), propylene oxide (PO) or butylene oxide (BO). Thus, for example, in one embodiment R2 may be a homopolymeric
polyoxyalkylene radical of the formula
R3 - ((EO))d- wherein in formula (III), a=1, b=0, c=0, Q=ethylene oxide, and R3 and d are as previously defined. In another embodiment, R2 may be a heteropolymeric polyoxyalkylene radical of the formula
R3 - ((EO)a (PO)b (BO)c)d- wherein, in formula III, Q=ethylene oxide, T=propylene oxide, Z=butylene oxide, and a, b, c, d and R, are as previously described.
In yet another preferred embodiment, the above- described amino compound reactant is selected from the group consisting of polyethylene polyamines,
polypropylene polyamines and mixtures thereof. In yet another preferred embodiment, such polyamines are monoalkylated.
The reaction product component is preferably prepared by reacting the substituted hydrocarbon R1-X to the amino compound in a mole ratio in the range of 0.2:1 - 20:1, more preferably in the range of 0.5:1 - 10:1. The reaction product component may be prepared under reaction conditions (including e.g. reaction times, temperatures, and reagent proportions) as are well known by those skilled in the art for preparing such amino compound-substituted hydrocarbon reaction
products. The method for preparing such reaction products is described, for example, in U.S. Pat. No. 3,172,892 (LeSeur et al.), U.S. Pat. No. 3,438,757 (Honnen et al.), and U.S. Pat. No. 3,443,918 (Kautsky et al.), all of which are incorporated herein by reference.
The detergent compound may also be a
polybutylamine or polyisobutylamine of the formula R
11 - CH
2 - N R
12 (IV)
R
13
where R11 is a polybutyl- or polyisobutyl radical derived from isobutene and up to 20% by weight of n- butene, and R12 and R13 are identical or different and are each hydrogen, an aliphatic or aromatic
hydrocarbon, a primary or secondary, aromatic or aliphatic aminoalkylene radical or polyaminoalkylene radical, a polyoxyalkylene radical or a hetaryl or heterocyclyl radical, or, together with the nitrogen atom to which they are bonded, form a ring in which further hetero atoms may be present.
Compounds of the general formula (IV) and the method of preparation thereof are disclosed, for example, in U.S. Pat. No. 4,832,702 (Kummer et al.), incorporated herein by reference. Compounds of the general formula (IV) are preferably prepared in accordance with the method disclosed in U.S. Pat. No. 4,832,702, wherein an appropriate polybutene or polyisobutene is hydroformylated with a rhodium or cobalt catalyst in the presence of CO and H2 at from about 80-200°C and CO/H2 pressures of up to 600 bar, and the oxo product thereby formed is then subjected to a Mannich reaction or amination under hydrogenating conditions, wherein the amination reaction is
advantageously carried out at 80-200°C and under pressures up to 600 bar, preferably 80-300 bar.
The fuel conditioner component employed in admixture with the detergent component to produce the additive of this invention may preferably be the fuel
conditioner previously disclosed in U.S. Pat. No.
4,753,661 (Nelson et al.), incorporated herein by reference. This fuel conditioner comprises a polar oxygenated hydrocarbon compound and an oxygenated compatibilizing agent.
The polar oxygenated hydrocarbon portion of the fuel conditioner signifies various organic mixtures arising from the controlled oxidation of petroleum liquids with air. Often these air oxidations of liquid distillates are carried out at a temperature of from about 100°C to about 150°C with an organo- metallic catalyst, such as esters of manganese, copper, iron, cobalt, nickel or tin, or organic catalysts, such as tertiary butyl peroxide. The result is a melange of polar oxygenated compounds which may be divided into at least three categories: volatile, saponifiable and non-saponifiable.
The polar oxygenated compounds preferable for use in the present invention may be characterized in a least three ways, by molecular weight, acid number, and saponification number. Chemically these oxidation products are mixtures of acids, hydroxy acids,
lactones, esters, ketones, alcohols, anhydrides, and other oxygenated organic compounds. Those suitable for the present invention are compounds and mixtures with an average molecular weight between about 250 and 500, with an acid number between about 25 and about 125 (ASTM-D-974), and a saponification number from about 30 to about 250 (ASTM-D-974-52). Preferably the polar oxygenated compounds of the present invention have an acid number from about 50 to about 100 and a saponification number from about 75 to about 200. An example of a polar oxygenated hydrocarbon within this preferred range is ALOX 400L (Alox Corporation,
Niagara Falls, New York).
Suitable compatibilizing agents for use in the fuel conditioner component of the instant invention are organic compounds of moderate solubility parameter
and moderate to strong hydrogen-bonding capacity.
Solubility parameters, δ, based on cohesive energy density are a fundamental descriptor of an organic solvent giving a measure of its polarity. Simple aliphatic molecules of low polarity have a low δ of about 7.3; highly polar water has a high δ of 23.4. Solubility parameters, however, are just a first approximation to the polarity of an organic solvent. Also important to generalized polarity, and hence solvent power, are dipole moment and hydrogen-bonding capacity. Symmetrical carbon tetrachloride and some aromatics with low gross dipole moment and poor hydrogen-bonding capacity have a solubility parameter of about 8.5. In contrast, methyl propyl ketone has almost the same solubility parameter, 8.7, but quite strong hydrogen-bonding capacity and a definite dipole moment. Thus, no one figure of merit describes the "polarity" of an organic solvent.
For the practice of the present invention a compatibilizing agent should have a solubility
parameter from about 8.8 to about 11.5 and moderate to strong hydrogen-bonding capacity. Suitable classes of organic solvents are alcohols, ketones, esters, and ethers. Preferred compatibilizing agents are
straight-chain, branched-chain, and alicyclic alcohols with from six to 14 carbon atoms. Especially
preferred compounds for compatibilizing agents are the hexanols, the heptanols, the octanols, the nonyl alcohols, the decanols, and the dodecanols.
The fuel conditioner component of this invention may additionally include a hydrophilic separant which decreases the amount of water in the hydrocarbon fuel, thus improving combustion. Suitable separants for practicing the current invention are ethers of glycols or polyglycols, especially monoethers. Monoethers are preferred over diethers in the practice of the present invention.
Examples of such compounds which may be used are the monoethers of ethylene glycol, propylene glycol, trimethylene glycol, alphabutylene glycol, 1,3- butanediol, beta-butylene glycol, isobutylene glycol, tetramethylene glycol, hexylene glycol, diethylene glycol, dipropylene glycol, tripropylene glycol, triethylene glycol, tetraethylene glycol, 1,5- pentanediol, 2-methyl-2-ethyl-1,3-propanediol, 2- ethyl-1,3-hexanediol. Some monoethers include
ethylene glycol monophenyl ether, ethylene glycol monomethylether, ethylene glycol monoethyl ether, ethylene glycol mono-(n-butyl) ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-(n-butyl) ether,
propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, diethylene glycol
monocyclohexylether, ethylene glycol monobenzyl ether, triethylene glycol monophenethyl ether, butylene glycol mono-(p-(n-butoxy) phenyl) ether, trimethylene glycol mono(alkylphenyl) ether, tripropylene glycol monomethyl ether, ethylene glycol mono-isopropyl ether, ethylene glycol monoisobutyl ether, ethylene glycol monohexyl ether, triethylene glycol monobutyl ether, triethylene glycol mnonomethyl ether,
triethylene glycol monoethyl ether, 1-butoxyethoxy-2- propanol, monophenyl ether of polypropylene glycol having an average molecular weight of about 975 to 1075, and monophenyl ether of polypropylene glycol wherein the polyglycol has a average molecular weight of about 400 to 450, monophenyl ether of polypropylene glycol wherein the polypropylene glycol has an average molecular weight of 975 to 1075. Such compounds are sold commercially under trade names such as Butyl CELLOSOLVE, Ethyl CELLOSOLVE, Hexyl CELLOSOLVE, Methyl CARBITOL, Butyl CARBITOL, DOWANOL Glycol ethers, and the like.
In the practice of the current invention, it has been found useful to include an aromatic hydrocarbon,
or a mixture of such, in the fuel conditioner
component of the present invention. Any aromatic hydrocarbon blend that is liquid at room temperature is suitable. Among these are benzene, toluene, the three xylenes, trimethylbenzene, durene, ethylbenzene, cumene, biphenyl, dibenzyl and the like or their mixtures. The preferred aromatic constituent is a commercial mixture of the three xylenes, because it is cheaper than any pure xylene. As used in this
description and in the appended claim, the word
"xylene" means not only the three specific xylene compounds o-xylene, m-xylene and p-xylene, but also includes aromatic "cuts" or distillates of aromatic hydrocarbons containing not only xylene but benzene, toluene, durene and naphthalene which may be mixed in the xylene. Aromatic naphthas are also useful.
Without being limited to any theory or hypotheses for the use of an aromatic hydrocarbon, it has been found that the presence of an aromatic hydrocarbon in the conditioner promotes clean and efficient combustion of the fuel.
The composition of this invention may
additionally comprise a suitable amount of a carrier oil or fluidizer selected from the group consisting of petroleum-based oils, mineral oils, polypropylene compounds having a molecular weight in the range of 500-3000, polyisobutylene compounds having a molecular weight in the range of 500-3000, polyoxyalkylene compounds having a molecular weight in the range of 500-3000, and polybutyl and polyisobutyl alcohols containing polybutyl or polyisobutyl radicals derived from polyisobutene and up to 20% by weight of n- butene, corresponding carboxylates of the polybutyl or polyisobutyl alcohol, and mixtures thereof. Petroleum based oils which may be employed include top cylinder oils as well as both natural and synthetic napthenic and paraffinic base stock oils of relatively high viscosity, including so-called Solvent Neutral Oils
(SNO) such as SNO-500 and SNO-600. Mineral oils which may be employed include so-called "light" mineral oils, i.e. those petroleum, aliphatic or alicyclic fractions having a viscosity less than 10,000 SUS at 25°C. A mixture of hydrocarbon fractions may also be employed in place of a base stock. The above- described polybutyl and polyisobutyl alcohols include those disclosed in U.S. Pat. No. 4,859,210 (Franz et al.), incorporated herein by reference. As used in this description and in the appended claims, the terms "carrier oil" and "fluidizer" are interchangeable, as will be readily understood by those skilled in the art.
Given the presence of the many constituents described above, a wide variety of proportions are suitable for the additive composition of this.
invention. Below a "Useful Range" and a "Preferred Range" are given in weight percent, based upon the total weight of the additive composition:
The additive composition of this invention may be employed in a wide variety of hydrocarbon or modified hydrocarbon (e.g. alcohol-containing) fuels for a variety of engines. Preferred motor fuel compositions for use with the additive composition of this
invention are those intended for use in spark ignition internal combustion engines. Such motor fuel
compositions, generally referred to as gasoline base stocks, preferably comprise a mixture of hydrocarbons boiling in the gasoline boiling range, preferably from
about 90-450°F. This base fuel may consist of
straight chains, branch chains, paraffins,
cycloparaffins, olefins, aromatic hydrocarbons, and mixtures thereof. The base fuel may be derived from, among others, straight run naptha, polymer gasoline, natural gasoline, or from catalytically cracked or thermally cracked hydrocarbons and catalytically reformed stock. The fuel may also contain synthetic hydrocarbons, ethers such as methyl tertiary butyl ether (MTBE), ethyl tertiary butyl ether (ETBE) and the like, alcohols such as methanol, ethanol, TBA and the like, and other functional organic compounds such as ketones, esters and the like. The composition and octane level of the base fuel are not critical and any conventional motor base fuel may be employed in the practice of this invention. In addition, the motor fuel composition may additionally comprise other additives typically employed in motor fuels, such as anti-knock compounds (e.g. tetraethyl lead), anti- icing additives, upper cylinder lubricating oils, carburetor detergents, anti-corrosion additives, de- emulsifying agents, odor suppressors, and the like.
Having described this invention above, it is now illustrated in the following examples. These
examples, however, do not limit the application of this invention, which may be carried out by other means in other systems.
Example 1
(Comparative Example)
Two automobiles (a Ford Escort and a Chevrolet Cavalier) were driven for 7000 miles (30% town
driving, 70% highway driving) using the same unleaded base gasoline containing no detergent additives, the gasoline having a (RON + MON)/2 octane number = 87. Before beginning the test, the engines were
disassembled and the combustion chambers thereof were
completely cleaned. They were then reassembled with new spark plugs and new valves.
After the 7000 mile driving test the engines were disassembled again and the deposits accumulated on the tulip of the inlet valves and in the combustion
chamber were collected and weighed. The results are
summarized below:
Car #1 Car #2
Automobile Make/Model Ford Escort Chevrolet Cavalier
Cylinders 1-4 V-6
Injector FI PFI
Inlet Valve 1.1 1.35
deposits (g)*
Combustion Chamber 0.95 1.1
deposits (g)* per unit
Example 2
(Comparative Example)
The identical test performed in Example 1 was
repeated except that each vehicle used an unleaded
base fuel containing a different commercially
available fuel detergent additive package at its
recommended level. After 7000 miles, the following results were obtained:
Car #1 Car #2
Additive Type A* B**
Inlet Valve 0.5 <0.1
deposits (g)
Combustion Chamber 1.45 1.7
deposits (g)
* Additive A = 250 ppm of a polybutene succinimide type additive*** + 500 ppm SNO 600.
** Additive B = 350 ppm of a polybutene amino type
additive*** + 600 ppm top cylinder oil.
*** Reaction products of a substituted hydrocarbon and an amino compound.
The results above indicate that although
commercial additives A and B improved inlet valve
cleanliness in comparison with Example 1, combustion chamber deposit formation actually increased, thereby detrimentally enhancing engine ORI.
Example 3
(Comparative Example)
The identical test performed in Example 1 was run, except that each vehicle used an unleaded base fuel containing 500 ppm of the fuel conditioner
component of this invention, as disclosed in U.S. Pat. No. 4,753,661 and available from Polar Molecular Corp. (Saginaw, Mi.) under the DurAlt Fuel Conditioner trade name.* The following results were obtained:
Car #1 Car # 2
Inlet Valve 1.27 1 . 45 deposits (g)
Combustion Chamber 0.48 0 . 5 deposits (g)
* Contained 30% (by weight of fuel conditioner)
active polar oxygenated compound.
Example 4
(Invention)
The identical test performed in Example 1 was run, except that each vehicle used an unleaded base fuel containing its respective additive (A or B) as in Example 2 plus 500 ppm of the fuel conditioner
component of this invention available from Polar
Molecular Corp. (Saginaw, Mi.) under the DurAlt Fuel Conditioner trade name. The following results were obtained:
Car #1 Car #2
Additive Type A+500ppm DurAlt B+500ppm DurAlt
Inlet Valve 0.35 <0.1 deposits (g)
Combustion Chamber 0.45 0.4 deposits (g) The results above show that the additive
composition of this invention, when employed in a motor fuel composition, reduces both inlet valve deposits and combustion chamber deposits, and hence tends to reduce engine ORI. These results are unexpected, in that the use of additives A and B without the DurAlt fuel conditioner (as in Example 2) showed much greater (i.e. 3-4 times greater)
combustion chamber deposit formation, and hence
greater ORI tendencies. Thus, the combination of the detergent and fuel conditioner components in the additive composition of this invention synergistically acts to reduce both intake valve deposit formation and combustion chamber deposit formation.
Example 5
(Invention)
The identical test performed in Example 1 was run, except that each vehicle used an unleaded base fuel containing its respective additive (A or B) as in Example 2 plus 300 pm and 100 ppm, respectively, of the DurAlt fuel conditioner. The following results were obtained:
Car #1 Car #2
Additive Type A+300ppm DurAlt B+lOϋppm DurAlt
Inlet Valve 0.37 <0.1
deposits (g)
Combustion Chamber 0.40 0.85 deposits (g) The results above again show that the additive composition of this invention, when employed in a motor fuel composition, reduces both inlet valve deposits 'and combustion chamber deposits, and hence tends to reduce engine ORI. These results are again unexpected, in that the use of additives A and B without the DurAlt fuel conditioner (as in Example 2) showed much greater (i.e. 2-3 times greater)
combustion chamber deposit formation, and hence greater ORI tendencies. Thus, the combination of the detergent and fuel conditioner components in the additive composition of this invention synergistically acts to reduce both intake valve deposit formation and combustion chamber deposit formation.
Example 6
(Comparative Example)
The identical test performed in Example 1 was run for Car #2, except that Car #2 used an unleaded base fuel having additive package B plus 500 ppm of a commercial fuel additive as disclosed in U.S. Patent No. 4,548,616 (Sung et al.), the additive being a poly (oxyethylene) (oxypropylene) polyol. Such additives are available from BASF Wyandotte Corp. under the PLURONIC series trade name. The following results were obtained:
Car #2
Additive Type B+500 ppm PLURONIC L-31*
Inlet Valve <0.1
deposits (g)
Combustion Chamber 1.2
deposits (g)
* PLURONIC L-31, a product of BASF Wyandotte Corp., is a poly (oxyethylene)-poly (oxypropylene)-poly (oxyethylene) polyol having a molecular weight of about 950 containing about 10 wt. % derived from poly (oxyethylene) and about 90% derived from poly (oxypropylene). The above results show that a combination of additive package B plus poly (oxyethylene) poly
(oxypropylene) polyol (PLURONIC L-31) is less
effective in controlling combustion chamber deposit formation, and hence engine ORI, than the additive of this invention, as exemplified in Examples 4 and 5.
Example 7
(Invention)
A Honda Accord, 1-4 engine with 2-barrel
carburetor and mileage of 64,550 miles, run primarily on leaded gasoline containing commercially available
additives, was found to have knocking problems. This vehicle was then run for 2000 miles on a fuel
containing an additive composition of this invention, namely an additive composition comprising additive B as set forth in Example 2 (i.e. 350 ppm polybutene amino type additive and 600 ppm top cylinder oil) + 500 ppm of DurAlt FC. The knocking problems totally disappeared, thus showing a clear reduction in engine ORI for this vehicle. This example illustrates the utility of this invention in so-called "clean-up" applications, wherein use of the invention improves performance of engines which have already demonstrated engine ORI.
Additional experimental results were obtained using a ES6500 Honda generator engine testing system. Two identical engine systems having identical loading (1500 and 2500 watt electrical resistance hot water heaters) were employed, in accordance with the testing procedure set forth in M. Megnin et al., "Development of a Gasoline Additive Screening Test for Intake Valve Stickiness and Deposit Levels," SAE Paper No. 892121 (presented at the Int'l Fuels and Lubricants Meeting, Baltimore, Md. Sept. 1989), incorporated herein by reference, which was modified as follows.
The engine was prepared for testing by first being disassembled. The intake valves were then cleaned with gum solvent consisting of a mixture of 1/3 acetone, 1/3 toluene, and 1/3 methanol to remove any lube oil on the valves. The valves were then stored in a desiccator for at least one hour, and thereafter weighed to the nearest 0.1 mg, just prior to engine assembly. The combustion chambers and ports were cleaned with a suitable wire brush, as were the tops of the pistons. The clean cylinder heads were reassembled and installed onto the engine, and the remainder of the engine was reassembled. The oil and oil filter were replaced prior to testing.
The fuel composition to be tested was prepared and poured into the fuel tank. The engine was started and allowed to idle for 30 second to warm up. The engine was then allowed to run under a 1500 watt load for two hours. At the end of the two hour period, the generator load, coolant in/out temperature, oil temperature, exhaust temperature for cylinders 1 and 2, and manifold vacuum were recorded. The engine was then run for an additional two hour period under a 2500 watt load. At the end of this two hour period, the above-described data were again recorded. The above-described four hour test run procedure was repeated (with intervening refueling) for 16 hours of engine running per day, for five consecutive, days. for a total of 80 hours of engine running. At the end of the 80 hour period, the generator fuel tank was drained and added to the remaining fuel mix for the run. The total volume of fuel remaining was measured to calculate the amount of fuel used during the 80 hour run.
After completion of the 80 hour run, the engine was disassembled , including removal of the cylinder head, cam shaft, and rocker arm assembly. The amount of deposits on the intake system, consisting of the carburetor throttle plate, intake manifold, head runners, head ports, and intake valves were rated using the method described by Coordinating Research Council (CRC) Rating Manual No. 16, Atlanta, Ga. 1987 ("CRC Rating"), which is well known to those skilled in the art. The combustion chamber and piston tops were similarly rated using the CRC Rating system. The sequence for rating, valve weighing, and photographing was as follows: the piston tops, cylinder head, combustion chamber, head runners, intake manifold, and throttle plate were all initially rated, and
photographed. The combustion side of the intake valves were thereafter cleaned, and the intake valves were removed carefully so as to not disturb any
deposits residing thereon. The valve stems were wiped with gum solvent to remove lube oil, and thereafter photographed. The valves were then placed in a desiccator for one hour and then removed and
immediately weighed, with the weight being recorded to the nearest 0.1 mg. The valves were then put back into the desiccator for an additional 0.5 hour and reweighted, this process was repeated until valve weighings were within 0.5 mg. The valve was then cleaned with gum solvent and wire brush, and stored in a desiccator until ready for final weighing. The engine was thereafter reassembled with a new set of intake valves, and the engine runs were repeated.
A base fuel composition obtained from the Sun Refining and Marketing Company was used in all of the following examples. The analysis of the base fuel composition was as follows:
Item Result
API Gravity, ASTM D287 56.1
Research Octane No., ASTM D2699 95.2
Motor Octane, ASTM D2700 84.2
Sensitivity, (R-M) 11.0
Octane, (R+M)/2 89.7
Reid Vapor Pressure, psi
ASTM D323 Automated 9.1
Distillation, ASTM D86
Automated
IBP 93
10% Evap. 131
50% Evap. 220
90% Evap. 336
FBP 411
Hydrocarbon Composition,
Vol. %, ASTM D1319
Aromatics 30.4
Olefins 17.1
Saturates 52.5
The base fuel composition, without any additives, was tested in each of the two Honda engine systems to obtain comparative results. Both intake valve deposit weights (in milligrams) and combustion chamber ratings
(according to the CRC method, as previously described) were obtained for each of the two engines as follows:
Example 8
(Comparative Example) Engine No. 1 Engine No. 2
Intake Valve Deposits (Mg)* 108.8 97.7
Combustion Chamber Rating 8.1 8.0 (CRC)** * Each is average of two runs
** In accordance with the CRC Rating Method, the
combustion chamber is rated from 1-10, with "1" being very "dirty" (i.e. very heavy deposits) and "10" being completely free of deposits. It is well known to those skilled in the art that reduction of combustion chamber deposits (i.e. high CRC Rating Number) can have a significant positive effect on ORI of vehicles as well as reduced amounts of exhaust emissions. A variety of fuel compositions, including fuel compositions containing the additive composition of this invention were tested using the above-described procedure in the Honda generator engines in order to obtain intake valve deposit measurements and
combustion chamber rating measurements. These test results are set forth below:
Example 9
Motor fuel compositions were prepared using the base fuel composition from Sun Refining and Marketing Company, and additionally having the following additives:
Detergent
Component Fuel
(250 mg/l Conditioner** Carrier Oil*
Fuel No. fuel Component (250 mo)
I
(compara— yes yes tive)
II polyiso-
(comparabutylamine
tive) — yes
III polyiso-
(invenbutylamine yes yes tion)
IV poly-
(comparabutylamine
tive) — yes
V poly-
(invenbutylamine yes yes tion)
VI isooctyl-
(comparaphenyl poly- tive) ethoxy ethanol — yes
VII isooctyl-
(invenphenyl poly- yes yes tion) ethoxy ethanol
* In Fuel Nos. I-VII, carrier oil used was 250 mg of 1:1 blend of SNO-600 oil and synthetic oil.
** Fuel conditioner component was 100mg/l fuel polar oxygenated hydrocarbon plus 40ppm compatibilizer (hexanol).
Fuels Nos. I-VII were rated in terms of the amount of intake valve deposits (in mg) and for combustion chamber (CRC) rating, as summarized in Figure 1. As is clear from Figure 2, which plots the data set forth in Figure 1, Fuel Nos. Ill, V, and VII (i.e. the fuel compositions comprising the additive of this invention) exhibited superior properties both in terms of combustion chamber rating (i.e. high CRC rating) and reduction of intake valve deposits (i.e. low value of mg of deposits on intake valves).
It will be evident that the terms and expressions employed herein are used as terms of description and not of limitation. There is no intention, in the use of these descriptive terms and expressions, of
5 excluding equivalents of the features described and it is recognized that various modifications are possible within the scope of the invention claimed.