US3374072A - Gasoline composition - Google Patents

Description

3,374,072 GASOLINE COMPOSITION John F. Deffner, Glenshaw, Pa., assignor to Gulf Research & Development Company, Pittsburgh, Pa., a corporation of Delaware N Drawing. Filed Mar. 23, 1966, Ser. No. 536,639 13 Claims. (CI. 44-58) ABSTRACT OF THE DISCLOSURE A gasoline motor fuel having improved detergency characteristics is obtained by incorporating a small amount of an amidophosphate in the fuel. The amidophosphate has the general formula:

Examples of amidophosphates falling within the above formula are dimethyl N-cocooxypropylmonoamidophosphate; distearyl N-cocooxypropylmonoamidophosphate; di(b-utoxyethyl) N-methoxypropylmonoamidophosphate; di(butoxyethyl) N butoxypropylmonoamidophosphate and di(butoxyethy1) N-cocooxypropylmonoamidophosphate.

This invention relates to fuels and more particularly to gasoline motor fuels for high compression spark ignition engines.

In operating a spark ignition engine under normal driv ing conditions, there is a tendency for deposits to form in the carburetor, particularly in the throttle body area of the carburetor. While deposits may form under any driving conditions, deposits are more likely to be formed in the carburetor of an engine operating at idle speeds during a considerable period of the operating time. Such driving conditions are normally encountered in engines of automobiles used to a great extent in driving in heavy traffic of the type encountered in city driving.

As deposits begin to build up in the throttle area of the carburetor, the clearance between the throttle plate and the body wall of the carburetor becomes progressively less. As the clearance is reduced theamount of air passing the throttle plate for a given amount of fuel is also reduced. As a result of a reduced amount of air, the airfucl mixture introduced into the combustion chamber is richer than it should be for satisfactory engine operation. As deposits continue to build up in the carburetor rough engine idling is encountered and eventually the engine will stall under idling conditions.

Excessive engine stalling is, of course, a source of annoyance due to the resulting increased fuel consumption, battery wear and inconvenience of frequent restarting. Thus, carburetors in which the deposits have built up must be cleaned and in some instances must be replaced before satisfactory engine performance is obtained.

The deposits which are formed in the carburetor may be due in part to the makeup of the motor fuel which is used, but it is believed that the deposits are due, to a greater extent at least, to foreign matter introduced into the carburetor through the air intake system. The air cleaners employed in automotive engines do not appear to effectively remove these contaminants. Major contributors to air contamination are crankcase vapors, exhaust vapors, dust, smoke andthe line. The problem with respect to carburetor deposits resulting from air contamination is further aggravated by the positive crankcase ventilating system which is employed in many of the current automotive engines. In engines equipped with United States Patent Ofifice 3,374,072 Patented Mar. 19, 1968 a positive crankcase ventilating system, fumes and/or vapors from the crankcase are passed through a metering valve into the air intake system of the engine. While this system helps to cut down on fumes escaping to the atmosphere, the system adds to the problem of deposits formed in the carburetor. Deposits are encountered not only in the carburetor but also in the components of the metering valve employed in connection with the positive crankcase ventilating system.

I have found that the formation of deposits in the carburetor of a spark ignition engine can be substantially reduced by incorporating in the gasoline motor fuel a small amount of an amidophosphate having the general formula where R and R are selected from the group consisting of alkyl, alkoxyalkyl and alkenyl radicals containing from 1 to 18 carbon atoms and cyclohexyl, phenyl, alkylphenyl, alkoxyphenyl, phenylalkyl, phenoxyalkyl and alkylphenoxyalkyl radicals wherein the alkyl portions of said alkylphenyl, alkoxyphenyl, phenylalkyl, phenoxyarlkyl and alkylphenoxyalkyl radicals contain from 1 to 8 carbon atoms; R is selected from the group consisting of alkyl and alkenyl radicals containing from 1 to 18 carbon atoms and cyclohexyl, phenyl, alkylphenyl and phenylalkyl radicals wherein the alkyl portions of said alkylphenyl and phenylalkyl radicals contain from 1 to 8 carbon atoms; R is selected from the group consisting of alkyl and alkenyl radicals containing from 1 to 18 carbon atoms and hydrogen; and n is an integer from 2 to 4.

Neither the R and R substituents attached through oxygen to the phosphorus atom nor the R and R substituents attached either directly or indirectly through oxygen and methylene groups to the nitrogen atom need be individual substituents; instead, these substituents can comprise mixtures of radicals derived from commercially available materials. For example, the alkyl substituents can be derived from a mixture of synthetically produced, isomeric, branched-chain alcohols such as are produced by the well-known Oxo synthesis process. Alternatively, the substituents can be derived from a mixture of fatty acid substituents such as those found in coconut oil fatty acids, babassu oil fatty acids, palm kernel oil fatty acids or other acids derived from naturally occurring fats or oils. When the substituents referred to above are derived from natural fats and oils, the mixed radicals will comprise homologous mixtures of alkyl, or alkyl and alkenyl radicals containing an even number of carbon atoms from 8 to 18. Thus, for example, the coco radical is a mixture of C C radicals (chiefly C alkyl) derived from coconut oil fatty acids.

The amidophosphates which are preferred for use in compositions of the invention are those in which R and R are the same alkyl or alkoxyalkyl radicals containing from 1 to 18 carbon atoms, R is an alkyl radical containing from 1 to 18 carbon atoms, R is hydrogen and n is 3. The latter amidophosphates are preferred because of their high gasoline solubility, ease of manufacture and low cost. The amidophosphates range from viscous liquids through wax-like compositions to solids.

The amount of the amidophosphate employed in the gasoline motor fuel composition of my invention may vary depending upon the base gasoline fuel employed and upon the particular amidophosphate selected. In most instances, a small amount within the range of about 0.001 to about 0.02 percent by weight has given good detergency characteristics to the gasoline. Excellent results have been obtained when the amidophosphate was employed in the gasoline in amounts corresponding to about 0.002 to about 0.006 percent by weight based on the weight of the gasoline, i.e., about to pounds of the amidophosphate per 1000 barrels of gasoline. While amounts in excess of 0.02 percent by weight can be employed without deleteriously affecting the other properties of the composition, such larger amounts do not give significantly improved detergency characteristics. Therefore, for economic reasons, I prefer to use no more of the amidophosphate than is necessary to give the desired improvement, that is, a small amount sufiicient to inhibit the formation of deposits in the carburetor of a spark ignition engine.

The amidophosphates which are used according to this invention can be prepared by known chemical methods which are reported in the literature. One such method is to react a disubstituted halophosphate having the general formula wherein R and R have the above set forth definitions and wherein X is a halogen atom, most particularly the chlorine atom though it may be another halogen such as bromine, with an amine having the following formula:

(III) rrn bucrrp on wherein R R and n have the same definitions as set forth above. The reaction is preferably conducted in the presence of a suitable halogen acid acceptor such as triethylamine and an organic solvent such as hexane, ethyl ether, etc. for the amidophosphate product. In accordance with this method, the hydrogen halide, e.g., hydrogen chloride which is freed during the reaction is bound by the halogen acid acceptor, e.g., triethylamine, resulting in the precipitation of triethylammonium chloride. The triethylammonium chloride can then be separated from the reaction mass by any suitable means, such as by filtration. The solvent, e.g., hexane, ethyl ether, etc. can then be removed from the reaction mass by any suitable means, e.g., vacuum distillation leaving the desired amidophosphate which can be further purified by treating a solution of the product with decolorizing charcoal. Those products which are solids may also be purified by recrystallization from an appropriate solvent.

Any disubstituted halophosphate falling within the general Formula II above can be used in preparing the amidophosphate of Formula I. Examples of some of the chlorophosphoric acid diesters which may be utilized in accordance with the present invention include:

While only chlorophosphoric acid esters have been illustrated above, it will be recognized that the corresponding bromoph-osphoric acid esters can also be used.

Exemplary of the amines falling within Formula III above whch can be used in preparing the amidophosphate of Formula I include:

(CH N(.CH OCH (C6H13) 2)a s 13 16 33) 2 4OC16H33 (CH CH) (H)N(CH OCH CH (CH CH CH) (H)N(CH OCH CHCH 9 1a= 9 17) 2)s 9 11= 9 1a Specific examples of some of the amidophosphates represented by the above structural formula (Formula I) and useful according to this invention include:

dimethyl N-methoxyethylmonoamidophosphate dirnethyl N-ethoxyethylmonoamidophosphate dimethyl N-propoxyethylmonoamidophosphate dimethyl N-butoxyethylmonoamidophosphate dimethyl N-pentoxyethylmonoarnidophosphate dimethyl N-hexoxyethylmonoamidophosphate dimethyl N-heptoxyethylmonoamidophosphate dimethyl N-octoxyethylmonoamidophosphate dimethyl N-nonoxyethylmonoarnidophosphate dimethyl N-decoxyethylmonoamidophosph-ate dimethyl N-undecoxyethylmonoamidophosphate dimethyl N-dodecoxyethylmonoarnidophosphate dirnethyl N-tridecoxyethylrnonoamidophosphate dimethyl N-hexadecoxyethylmonoamidophosphate dimethyl N-octadecoxyethylmonoarnidophosphate dimethyl N-vinyloxyethylmonoamidophosphate dimethyl N-pr'openoxyethylmonoarnidophosphate dimethyl N-octadecenoxyethylmonoamidophosphate dimethyl N-methoxypropylmonoarnidophosphate dimet-hyl N-butoxypropylmonoamidophosphate dimethyl N-octoxypropylmonoamidophosphate dimethyl "N-dodecoxypropylmonoamidophosphate dimethyl' N-hexadecoxypropylmonoamidophosphate dimethyl N-octadecoxypropylmonoamidophosphate dimethyl N-vinyloxypropylmonoarnidophosphate dimethyl N-octadecenoxypropylmonoamidophosphate dimethyl N-cyclohexoxypropylmonoamidophosphate dimethyl N-phenoxypropylmonoamidophosphate dimethyl N-toloxypropylmonoamidophosphate dimethyl N-benzoxypropylmonoamidophosphate dimethyl N-isooctylphenoxypropylmonoamidophosphate dmethyl N-rnethoxybutylmonoamidophosphate dimethyl N-butoxybutylmonoamidophosphate dirnethyl N-oct0xybutylmonoamidophosphate dir nethyl N-dodecoiybutylmbnoamidophosphate dimethyl N-hexadecoxybutylmonoamidophosphate dimethyl N-octadecoxyhutylmonoamidophosphate' dimethyl N-vinyloxybutylmonoamidophosphate dimethyl N-0ctadecenoxybutylmonoamidophosphate diethyl N-methoxyethylmonoamidophosphate dipropyl N-butoxypropylmonoamidophosphate dl'butyl N-octoxybutylm onoamidophosphate diamyl N-dodecoxyethylmonoamidophosphate dihexyl N-hexadecoxypropylmonoamidophosphate diheptyl N-00tadecoxybutylmonoarnidophosphate dioctyl N-vinyloxyethylmpnoamidophosphate dinonyl N-octadecenoxypropylmonoamidophosphate didecyl N-methoxybutylrnonoamidophosphate diundecyl N-butoxyethylmonoamidophosphate didodecyl N-octoxypropylmonoamidophosphate ditridecyl N-dodecoxybutylmonoamidophosphate ditetradecyl N-hexadecoxyethylmonoamidophosphate dipentadecyl N-octadecoxypropylmonoamidophosphate dihexadecyl N-vinyloxybutylmonoamidophosphate diheptadecyl N-octadecenoxyethylmonoamidophosphate dioctadecyl N-metho'xypropylmonoamid ophosphate divinyl N-butoxybutylmonoamidophosphate dipropenyl N-octoxyethylrnonoamidophosphate dioctadecenyl N-dodecoxypropylmonoamidophosphate di(methoxymethyl) N-hexadecoxybutylmonoatnidophosphate dihillethoxypropyl) N-octadecoxyethylmonoamidophosp ate di(ethoxyethyl) N-vinyloxypropylmonoamidophosphate di(ethoxypropyl) N-0ctadecenoxybutylmonoamidophosphate di(ethoxybutyl) N-methoxyethylrnonoamidophosphate di(ilslopropoxymethyl) N-butoxypropylmonoamidophosp ate di(butoxyethyl) N-octoxybutylmonoamidophosphate dlUZgltOXYPIOPYl) N-dodecoxyethylmonoamidophosp ate dicyclohexyl N-hexadecoxypropylmonoamidophosphate diphenyl N-octadecoxybutylmonoamidophosphate ditolyl N-vinyloxyethylmonoarnidophosphate dixylyl N-octadecenoxypropylmonoamidophosphate dihgethoxyphenyl) N-methoxybutylmon oamidophosp ate dibenzyl N-butoxyethylmonoamidophosphate di(phenylethyl) N-octoxypropylmonoamidophosphate di(phenylpropyl) N-dodecoxybutylmonoamidophosphate diqilhenoxymethyl) N-hexadecoxyethylmonoarnidophosp ate di(1'sooctylphenoxymethyl) N-octadecoxypropylmonoamidophosphate dimethyl N-rnethyl-N-methoxybutylrnonoamiclophosphate diethyl N-ethyl-N-ethoxyethylmonoarnidophosphate diprlfpyl N-propyl-N-propoxypropylmonoamidophosp ate 7 dibutyl N-butyl-N-butoxybutylrnonoamidophosphate diarnyl N-amyl-Npentoxyethylmonoamidlo phosphate dihexyl N-hexyl-N-hexoxypropylmonoamidophosphate diheptyl N-heptyl-Nheptoxybutylmonoannidophosphate dioctyl Noctyl-N-octoxyethylmonoamidophosphate dinonyl N-nonyl-N-nonoxypropylmonoamidophosphate didecyl N-decyl-N-decoxybutylmonoarnid ophosphate diundecyl N-undecyl-N-undecoxyethylmonoarnidophosphate didodecyl N-dodecyl-N-dodecoxypropylmonoamidophosphate ditridecyl N-tridecyl-N-tridecoxybutylmonoamidophosphate ditetradecyl N-tetradecyl-N-tetradecoxyethylmonoamid0- phosphate dipentadecyl N-pentadecyl-N-pentadecoxy'prcpylmonoamidophosphate dihexadecyl N-heXadecyl-N-hexadecoxybutylmonoamidophosphate diheptadecyl N-heptadecyl-N-heptadecoxyethylmonoamidophosphate dioctadecyl N-0ctadecyl-N-octadecoxypropylrnonoamidophosphate divinyl N-vinyl-N-vinyloxybutylmonoarnidophosphate dipropenyl N-propenyl-N-propenoxyethylmonoamidophosphate dioctadecenyl N-octadecenyl-N-octadecenoxypropylmonoamidophosphate methyl ethyl N-methoxyethylmonoamidophosphate methyl propyl N-methoxypropylmonoamidophosphate methyl butyl N-methoxybutylmonoamidophosphate ethyl hexyl N-methoxyethylmonoamidophosphate ethyl octyl N-rnethoxypropylmonoamidophosphate ethyl dodecyl N-methoxybutylmonoamidophosphate ethyl hexadecyl N-methoxyethylrnonoamidophosphate EXAMPLE I (Distearyl N-cocooxypropylmonoamidophosphate) Octadecanol (162.3 parts) was mixed with 640 parts of carbon tetrachloride. While stirring the mixture, a solution consisting of 27.5 parts of phosphorus trichloride in 80 parts of carbon tetrachloride was added over a period of about 15 minutes. The solution thus obtained was heated slowly on a water bath to 100 C. over a hour period while introducing air into the solution to drive off hydrogen chloride and carbon tetrachloride. Final traces of volatile components were removed under reduced pressure. The byproduct, l-chlorooctadecane, was removed from the residue by distilling it under reduced pressure (B.P. 140156 C. at 1 mm. mercury). The residue (110.7 parts) comprised distearyl phosphite, a pale yellow, waxy solid which melted at 56-58 C.

Distearyl phosphite (104 parts) thus obtained was then dissolved in 1600 parts of carbon tetrachloride. The solution was then cooled to 2 C. Thereafter, chlorine was bubbled into the solution at a rate to maintain the temperature of the solution at 5 to 7 C. In a period of about 25 minutes, a total of 100 parts of chlorine was added. Air was passed through the solution for about 2 hours. The aerated solution was then treated with lead carbonate to remove traces of hydrogen chloride. The mixture was filtered after which the solvent (carbon tetrachloride) was stripped from the filtrate under reduced pressure. The residue (106 parts) comprised distearyl chlorophosphate, a waxy yellow solid which melted at 47 C.

To a portion of the distearyl chlorophosphate (62 parts) thus obtained were added triethylamine (20.2 parts) and hexane (240 parts). The solution thus obtained was stirred while introducing a solution consisting of 24.3 parts of cocooxypropylamine in 33 parts of hexane over a 10 minute period. The mixture was heated to reflux and refluxing was continued for 3.5 hours. The mixture was filtered while it was still hot. The solvent (hexane) was removed from the filtrate under reduced pressure. The residue (82.5 parts) was a waxy, light brown solid which melted at 5359 C. The product was treated with decolorizing charcoal and recrystallized from acetone to yield 65 parts of a waxy, white solid which melted at 55-60 C. Elemental analysis of the waxy, white solid product shows it to compare favorably with the theoretical analysis of distearyl N-cocooxypropylmonoamidophosphate.

Percent by weight for distearyl N-cocooxypropylmonoamidophosphate.-Found: C, 74.07; H, 13.07; P, 3.50; N, 1.46. Theoretical: C, 73.95; H, 12.90; P, 3.74; N, 1.69.

EXAMPLE II (Dimelhyl N-cocooxypropylmonoamia'ophosphale) Triethylamine (10.1 parts) and dimethyl chlorophosphate (14.4 parts) were dissolved in ethyl ether (60 parts). The solution thus obtained was stirred while introducing a solution consisting of 24.4 parts of cocooxypropylamine in 15 parts of ethyl ether over a 10 minute period. The mixture was then refluxed for 12 hours. The mixture was filtered While it was still hot. The solvent (ethyl ether) was removed from the filtrate under reduced pressure. The product (22 parts) from which the ethyl ether was removed comprised dimethyl N-cocooxypropylmonoamidophosphate, a viscous brown liquid.

EXAMPLE III [Di (butoxyethyl) N -c0c00xy propylmonoamidophosphate] Butoxyethyl alcohol (354.5 parts) was cooled in an ice bath to 5 C. Phosphorus trichloride (137.4 parts) was added dropwise to the cooled butoxyethyl alcohol over a period of about 1.25 hours. The temperature of the reaction mass was maintained at 5 to 10 C. during the addition of the phosphorus trichloride. When the addition of the phosphorous trichloride was complete, nitrogen was bubbled through the reaction mass while heating to C. on a water bath. The product thus obtained was stirred with sodium carbonate to remove traces of hydrogen chloride. The reaction mass was filtered and the filtrate was distilled under reduced pressure. The fraction boiling at 133 to 136 C. at 1 mm. mercury was collected. The yield was 164 parts of a water white liquid. Elemental analysis of the water white liquid shows it to compare favorably with the theoretical analysis of di(butoxyethyl) phosphite.

Percent by weight for di(butoxyethyl)phosphite.-- Found: C, 50.95; H, 9.69; P, 10.98. Theoretical: C, 51.05; H, 9.64; P, 10.97.

Di(butoxyethyl)phosphite (70.5 parts) thus obtained was then dissolved in 400 parts of carbon tetrachloride. The solution was then cooled to 2 C. Thereafter, chlorine was bubbled into the solution at a rate to maintain the temperature of the solution at 5 to 7 C. In a period of about 25 minutes, a total of 21 parts of chlorine was added. Air was passed through the solution for about 2 hours. The aerated solution was then treated with lead carbonate to remove traces of hydrogen chloride. The mixture was filtered after which the solvent (carbon tetrachloride) was stripped from the filtrate under reduced pressure. The product (72.4 parts) comprised di(butoxyethyl)chlor ophosphate, a yellow liquid, n 1.4407. Elemental analysis of this liquid for phosphorus and chlorine shows it to compare favorably with the corresponding theoretical analysis of di(butoxyethyl)chlorophosphate for these elements.

Percent by weight for di(butoxyethyl)chlorophosphate.-Found: P, 9.77; Cl, 11.3. Theoretical: P, 9.78; Cl, 11.19.

To a portion of the di(butoxyethyl)chlorophosphate (31.7 parts) thus obtained were added triethylamine (20.2 parts) and hexane parts). The solution thus obtained was stirred while introducing cocooxypropylamine (24.3 parts) dropwise over a period of 30 minutes. The mixture was refluxed for 3 hours. The mixture was filtered while it was still hot. The filter cake was washed with 50 parts of hexane. The filtrate and washings were combined and treated with decolorizing carbon. The mix ture was filtered and solvent (hexane) was removed from the filtrate under vacuum. The product comprised 50 parts of a light brown liquid n 1.4498. Elemental analysis of the light brown liquid shows it to compare favorably with the theoretical analysis of di(butoxyethyl) N-cocooxypropylmonoamidophosphate.

Percentby weight for di(butoxyethyl) N-cocooxypropylmonoamidophosphate.--Found: C, 61.39; H, 10.96; P, 5.75; N, 2.69. Theoretical: C, 61.92; H, 11.16; P, 5.91; N, 2.67.

9 EXAMPLE IV [Di (butoxyethyl) N-methoxypropylmonoamidophosphute] 3-methoxypropylamine parts) was dissolved in 130 parts of hexane. The solution thus obtained was stirred while introducing over a period of 15 minutes a portion of the di(butoxyethyl)chlorophosphate (15.8 parts) obtained in Example III. The mixture was refluxed for 2 hours. The mixture was filtered while it was still hot. The filter cake was washed with 50 parts of hexane. The filtrate and washings were combined. The combined solution was then washed with 100 parts of water. The hexane solution was separated from the water and dried over sodium sulfate. The mixture was then filtered after which hexane was removed from the filtrate under vacuum to yield 13.2 parts of light brown liquid. Elemental analysis of the light brown liquid shows it to compare favorably with the theoretical analysis of di-(butoxyethyl) N-methoxypropylmonoamidophosphate.

Percent by weight for di(butoxyethyl) N-methoxypropylmonoamidophosphate.-Found: C, 52.04; H, 9.47; P, 8.10; N, 3.53. Theoretical: C, 52.02; H, 9.82; P, 8.38; N, 3.79.

EXAMPLE V [Di (butoxyethyl) N-buloxypropylmonoamidophosphate] To a portion of the di(butoxyethyl)chlorophosphate 14.6 parts) obtained in Example III were added triethylamine (20.2 parts) and hexane (125 parts). The solution thus obtained was stirred while introducing 3-butoxypropylamine (6.0 parts) dropwise over a period of minutes. The mixture was refluxed for 3 hours. The mixture was filtered while it was still hot. The filter cake was washed with parts of hexane. The filtrate and washings were combined and treated with decolorizing carbon. The mixture was filtered and solvent (hexane) was removed from the filtrate under vacuum. The product comprised 18.3 parts of a viscous, light brown liquid. Elemental analysis of the light brown liquid for nitrogen and phosphorus shows it to compare favorably with the corresponding theoretical analysis of di(butoxyethyl) N-butoxypropylmonoamidophosphate for these elements.

Percent by weight for di(butoxyethyl) N-butoxypropylmonoamidophosphate.-Found: P, 7.53; N, 3.51. Theoreticalf P, 7.53; N, 3.40.

The gasoline fuel composition to which the amidophosphate is added includes substantially all grades of gasoline presently being employed in automotive and internal combustion aircraft engines. Such gasolines comprise a mixture of hydrocarbons which can be obtained by at least one of the petroleum conversion processes including cracking, alkylation, aromatization, cyclization, isomerization, hydrogenation, dehydrogenation, hydroisomerization, polymerization, hydroforming, polyforming, Platforming and combinations of two or more such processes, as well as by the Fischer-Tropsch and related processes. Thus, the term gasoline is used herein in its conventional sense to include hydrocarbons boiling in the gasoline boiling point range. While current straight-run gasoline has octane numbers too low to qualify as the sole hydrocarbon component of gasoline fuel compositions having desirably high octane numbers, a small amount of straight-run gasoline can be blended with the hydrocarbon mixture obtained by one or more of the designated conversion processes provided the resulting mixture has a motor octane number (leaded) of at least about 80 and a research octane number (leaded) of at least about 90. A preferred gasoline fuel composition comprises a blend of hydrocarbons obtained by catalytic cracking, Platforming and alkylation processes.

The amidophosphates can be employed individually or in the form of a mixture of two or more such compounds. In addition to the amidophosphate compound, the gasoline motor fuel composition of myinvention can contain conventional amounts of additives commonly employed in a commercial motor fuel including a tetraalkyl lead, an upper cylinder lubricant, a corrosion and oxidation inhibitor, an alkyl halide lead scavenging agent, an alcoholic anti-stalling agent, a metal deactivator, a deh'azing agent, an anti-rust additive, an ignition control agent, a dye and the like. Suitable gasolines may contain up to about 5 cubic centimeters of a tetraalkyl lead fluid, e.g., tetraethyl lead fluid, per gallon of gasoline.

When an upper cylinder lubricant is employed it is generally used in an amount of from about 0.25 to about 0.75 percent by volume of the composition, e.g., 0.5 volume percent. This oil should be a light lubricating oil distillate, e.g., one having a viscosity at F. of from about 50 to about 500 Saybolt Universal seconds, e.g., about 100 SUS. Although highly paraffinic lubricating distillates can be used, lubricating distillates obtained from Coastal or naphthenic type crude oils are preferred because of their superior solvent properties. The lubricating oil can be solvent-treated, acidtreated, or otherwise refined.

When an oxidation inhibitor is desired, any of the conventional inhibitors can be utilized. The alkylated phenols, e.g., 2,4,6 tri tertiary-butylphenol, 2,6-di-tertiary butyl-4-methylphenol, 2,2-bis(2-hydroxy-3-tertiarybutyl 5 methylphenyl)propane and bis(2-hydroxy-3- tertiary-butyl-S-methylphenyl)methane, because of their hydrocarbon-solubility and water-insolubility characteristics are preferred oxidation inhibitors. Such inhibitors when used are incorporated in the gasoline fuel composition in amounts of from about 0.001 to about 0.02 percent by weight of the composition, e.g., 0.007 Weight percent.

When an ignition control agent is employed such as an organo phosphorus compound, its amount is usually expressed in terms of that which is theoretically required to convert the lead introduced into the fuel in the form of tetraalkyl lead to lead orthophosphate. While improved results can be obtained in some instances with amounts corresponding to about 0.1 times the amount theoretically required to convert the lead to lead phosphate, it is generally preferred to use an amount equal to about 0.2 to about 0.5 times the amount theoretically required to convert the lead to lead orthophosphate. In view of the fact that the amount of tetraalkyl lead in gasoline varies from one fuel to another, it is difficult to state on a weight basis the amount of a particular compound based upon the weight of the gasoline. However, once knowing the amount of tetraalkyl lead present in the gasoline, it is an easy matter to calculate the amount of the particular compound required on a weight basis. Most gasolines on the market contain between about one and about three cubic centimeters of tetraethyl lead per gallon of gasoline. Based upon such a lead content, the phosphorus compounds maybe used in amounts corresponding to about 0.006 to about 0.1 percent by weight based on the Weight of the fuel. At any rate, the amount should be sufiicient to incorporate between about 0.1 and about 1.0, preferably about 0.2 to about 0.5 times the amount of phosphorus required to convert the lead to lead orthophosphate. Exemplary of the organo phosphorus ignition control agents are: Trimethyl phosphate, tributyl phosphate, triphenyl phosphate, tricresyl phosphate, trixylyl phosphate, dimethyl xylyl phosphate, cresyl diphenyl phosphate, dicresyl phenyl phosphate, methyl diphenyl phosphate, methyl dicresyl phosphate, ethyl dicresyl phosphate, diisopropyl phenyl phosphate, dibutyl phenyl phosphate, diisoamyl cyclohexyl phosphate, tri(butoxyethyl) phosphate, trimethyl phosphite, triethyl phosphite, tributyl phosphite, triisooctyl phosphite, diethyl amyl phosphite, diisopropyl ethyl phosphite, dimethyl ethyl phosphite, diethyl methyl phosphine, diethyl propyl phosphine, diethyl isoamyl phosphine, tributyl phosphine and the like.

Exemplary of another specific improvement agent Which I can use is N,N'-disalicylidene-1,2-diaminopropane as a metal deactivator. The metal deactivator is generally used in small amounts of the order of about 0.0003 to about 0.001 percent by weight based on the fuel composition.

In order to illustrate improved detergency of fuels containing an amidophosphate, a gum-forming fuel was compared with the same fuel containing about 0.006 percent by Weight (15 pounds per 1000 barrels) of representative amidophosphates prepared as described hereinabove. The comparison was made in accordance with a Modified Intake System Deposit (ISD) Detergency Test. This test comprises forming a gum deposit in the test apparatus by evaporating the test fuel in the apparatus by flowing a stream of heated air counter-current to the fiow of the fuel. At the completion of the test, the Weight of the adhering gum is determined and compared to the reference fuel (without additives) for an appraisal of the additives detergency action. The apparatus which is employed is described by C. C. Moore, J. L. Keller, W. L. Kent and F. S. Liggett, Evaluating Gasoline for Engine Induction System Gums, The Petroleum Engineer, vol. 27, N0. 12, pages Cl930 (1955). In conducting the test, a gum deposit is formed on the walls of a steam-jacketed U-tube by evaporating two liters of fuel admitted to the system counter-current to a stream of preheated air. The Utube is then washed with a number of portions of naphtha until a final wash shows no discoloration. The amount of gum adhering to the apparatus is then determined by extracting it with chemically pure acetone, evaporating the acetone extract with filtered, heated air to obtain a gum residue which is then heated in an oven /2 hour at 100 12 It is evident from the data in Table I that a fuel containing an amidophosphate as herein described has improved detergency characteristics over the base fuel, the fuel containing di(butoxyethyl) N-butoxypropylmonoamidophosphate showing an excellent improvement of 76 percent.

In order to further illustrate the improved detergency characteristics of fuel compositions containing an amidophosphate as herein described, engine tests were conducted on a base fuel and compounded base fuel. According to the test procedure followed, the fuel compositions are burned in a 371 cubic inch, eight cylinder, Oldsmobile engine equipped with a 2-barrel carburetor. In this test, the engine is operated for 100 cycles, each cycle consisting of 36 minutes operation at idle (650150 r.p.m.) with no load and 12 minutes at 1800: r.p.m. with a load of 15 brake horsepower. Prior to each test, the crankcase of the engine is flushed with new lubricating oil for a period of ten minutes, a new oil filter is installed and a clean carburetor is installed. The test starts under the idling portion of the cycle. The jacket temperature is maintained at 175:5 F. during the test period. The air to fuel ratio is set, during idle condition, at 10.5 (:03) to 1 at the beginning of each test. The duration of the test is hours. The crankcase of the engine contains a 20/ 20W, non-detergent oil. At the conclusion of each 80-hour test, the carburetor is removed and examined. The carburetor throat is visually rated, using 0 to denote a clean rating and 22 to signify a maximum deposit rating. The makeup of the fuels tested and the results of the engine tests are shown in Table II. Two tests were run on each fuel to obtain comparative results.

TABLE II Fuel Composition A B C D E F 1133s: (giasoline, Volume percent 100 100 100 100 100 e Tetraethyl lead, Ml. Gal 3. 0 3. 0 3. 0 3. 0 3. Methyl diphenyl phosphate: 0 3 0 Theory O. 2 0. 2 100/2 Texas Oil, Volume percent 0.5 0.5 0.5 0.5 0. 5 Distearyl N-eocooxypropylmonoamidophosphate, lbs/M bbls 15 Distearyl N-cocooxypropylmonoamidophosphate (Example I), lbs/M bbls 15 D1(butoxyethyl) N-cocooxypropylmonoamidophosphate (Example III), lbs/M bbls 15 Engine Tests-Carburetor Throat Rating 2 Test No. l..- .50 5.50 Test No.2. .75 7. 25

1 A commercially available material. 2 Rating of 0 denotes clean condition. Rating of 22 denotes very heavy deposits.

C.), cooled and weighed as noted in the published procedure. Results of the determinations using the same fuel with and without additives are compared in order to evaluate detergency action. Table I summarizes the results obtained in the Modified Intake System Deposit (ISD) Detergency Test.

TABLE I Modified 18D Test Composition Weight of Improve Adhering ment over Deposits, Base Fuel,

Mg. percent Base gasoline fuel A Base gasoline fuel B Base gasoline fuel C Base gasoline fuel A 15 pounds of distearyl N -cocooxypropylmonoamidophosphate (Example I) per 1,000 barrels of fuel.

Base gasoline fuel 13 15 pounds of dimethyl N-eocooxypropylrnonoamidopfhfosphate (Example 11) per 1,000barrels 0 ue.

Base gasoline fuel A 15 pounds of di- (butoxyethyl) N-cocooxypro ylmonoamidophosphate (Example I I) per 1,000 barrels of fuel.

Base gasoline fuel 0 15 pounds of di- (butoxyethyl) N-methoxypropylrnonoamidophosphate (Example IV) per 1,000 barrels of fuel.

Base gasoline fuel C 15 pounds of di- (butoxyethyl) N -butoxypropylmonoamidophosphate (Example V) per 1,000 barrels of fuel.

The data in Table II clearly demonstrate the marked superiority of gasoline motor fuel compositions of the invention (Compositions D, E and F) over the comparative gasoline compositions containing no amidophosphate (Compositions A, B and C). It will be noted that while Composition B containing a small amount of Texas oil and Composition C containing a small amount of methyl diphenyl phosphate and Texas oil gave improved carburetor ratings over the base gasoline, the improvement was not as marked as with Compositions D, E and F which also contained an amidophosphate.

While my invention has been described with reference to various specific examples and embodiments, it will be understood that the invention is not limited to such examples and embodiments and may be variously practiced within the scope of the claims hereinafter made.

I claim:

1. A gasoline motor fuel composition comprising a major amount of gasoline and a small amount, sufficient to inhibit deposits in the carburetor of a spark ignition engine, of an amidophosphate having the general formula:

where R and R are selected from the group consisting of alkyl, alkoxyalkyl and alkenyl radicals containing from 1 to 18 carbon atoms and cyclohexyl, phenyl, alkylphenyl, alkoxyphenyl, phenylalkyl, phenoxyalkyl and alkylphenoxyalkyl radicals wherein the alkyl portions of said alkylphenyl, alkoxyphenyl, phenylalkyl, phenoxyalkyl and alkylphenoxyalkyl radicals contain from 1 to 8 carbon atoms; R is selected from the group consisting of alkyl and alkenyl radicals containing from 1 to 18 carbon atoms and cyclohexyl, phenyl, alkylphenyl and phenylal-kyl radicals wherein the alkyl portions of said alkylphenyl and phenyl-alk-yl radicals contain from 1 to 8 carbon atoms; R is selected from the group consisting of alkyl and alkenyl radicals containing from 1 to 18 carbon atoms and hydrogen; and n is an integer from 2 to 4.

2. The gasoline lmotor fuel composition of claim 1 wherein the amidophosphate is present in an amount of about 0.001 to about 0.02 percent by weight of the composition.

3. The gasoline motor fuel composition of claim 1 wherein the gasoline normally tends to form deposits in the carburetor of a spark ignition engine and the amidophosphate is present in an amount sufiicient to inhibit the formation of said deposits.

4. A gasoline motor fuel composition comprising a major amount of gasoline and a small amount, sufficient to inhibit deposits in the carburetor of a spark ignition engine, of an amidophosphate having the general formula:

where R and R are the same radicals selected from the group consisting of alkyl and alkoxyalkyl radicals containing from 1 to 18 carbon atoms and R is an alkyl radical containing from 1 to 18 carbon atoms.

5. The gasoline motor fuel composition of claim 4 wherein the amidophosphate is present in an amount of about 0.001 to about 0.02 percent by weight of the composition.

6. The gasoline motor fuel composition of claim 4 wherein the gasoline normally tends to form deposits in the carburetor of a spark ignition engine and the amidophosphate is present in an amount sufiicient to inhibit the formation of said deposits.

7. The gasoline motor fuel composition of claim 4 wherein the amidophosphate is distearyl N-cocooxypropylmonoamidophosphate.

8. The gasoline motor fuel composition of claim 4 wherein the amidophosphate is dimethyl N-cocooxypropylmonoamidophosphate.

9. The gasoline motor fuel composition of claim 4 wherein the amidophosphate is di(butoxyethyl) N-cocooxypropylmonoamidophosphate.

10. The gasoline motor fuel composition of claim 4 wherein the amidophosphate is di( butoxyethyl) N-methoxypropylrnonoamidophosphate.

11. The gasoline motor fuel composition of claim 4 wherein the amidophosphate is di(butoxyethyl) N-butoxypropylmonoamidophosphate.

12. A gasoline motor fuel composition comprising a major amount of gasoline containing up to about 5 cubic centimeters of tetraethyl lead per gallon of gasoline; about 0.003 to about 0.1 percent by weight of methyl diphenyl phosphate, the methyl diphenyl phosphate comprising at least 0.1 times the theoretical amount required to convert the lead in said tetraethyl lead to lead phosphate; about 0.001 to about 0.02 percent by Weight of distearyl N-cocooxypropylmonoamidophosphate; and about 0.25 to about 0.75 percent by volume of a light lubricating oil having a viscosity at 100 F. of from about to about 500 Saybolt Universal seconds.

13. A gasoline motor fuel composition comprising a major amount of gasoline containing up to about 5 cubic centimeters of tetraethyl lead per gallon of gasoline; about 0.003 to about 0.1 percent by weight of methyl diphenyl phosphate, the methyl diphenyl phosphate comprising at least 0.1 times the theoretical amount required to convert the lead in said tetraethyl lead to lead phosphate; about 0.001 to about 0.02 percent by weight of di('butoxyethyl) N-cocooxypropylmonoamidophosphate; and about 0.25 to about 0.75 percent by volume of a light lubricating oil having a viscosity at F. of from about 50 to about 500 Saybolt Universal seconds.

References Cited UNITED STATES PATENTS 2,956,869 10/ 1960 DeGray 44-63 3,000,709 9/ 1961 Orloff et al. 44-63 DANIEL E. WYMAN, Primary Examiner. W. J. SHINE, Assistant Examiner.