WO2021240117A1 - Use of a fuel composition comprising three additives for cleaning the internal parts of petrol engines - Google Patents

Abstract

The present invention relates to the use, for reducing deposits in the internal parts of a spark ignition engine, of a fuel composition comprising at least three additives: a quaternary ammonium salt, a non-quaternary polyisobutylene succinimide and a Mannich base which is different from the other additives. The composition is such that the mass ratio of the quantity of the first additive to the quantity of the second additive is in the range from 0.2: 1 to 2.5: 1.

Description

DESCRIPTION

TITLE: USE OF A FUEL COMPOSITION CONTAINING 3 ADDITIVES TO CLEAN THE INTERNAL PARTS OF ENGINES

ESSENCE

The present invention relates to the use, for reducing and / or preventing deposits present in the internal parts of a spark ignition engine, of a fuel composition which comprises at least three additives: a quaternary ammonium salt, a non-quaternary polyisobutylene succinimide, and a Mannich base, different from the other two additives. The composition is such that the mass ratio of the amount of the first additive to the amount of the second additive is in the range from 0.2: 1 to 2.5: 1.

The invention also relates to the use, for improving the detergency properties of gasoline fuel, of a fuel concentrate comprising at least said three additives, in admixture with an organic liquid inert to said additives.

The composition is also used to maintain cleanliness (keep-clean effect) and / or to clean (clean-up effect) deposits in the engine, as well as to reduce the fuel consumption of the engine (“Fuel Eco” action) and / or minimize the loss of power of said engine, and / or reduce the emissions of pollutants, in particular, the emissions of particles from the combustion engine, and / or to reduce the clogging of the pistons of the engine, preferably in direct gasoline injection ( or IDE).

STATE OF THE PRIOR ART

Liquid internal combustion engine fuels contain components that can be degraded during engine operation. The problem of deposits in the internal parts of combustion engines is well known to engine manufacturers. It has been shown that the formation of these deposits has consequences on engine performance and in particular has a negative impact on fuel consumption and particle emissions (Gueit, J. et al., "Injector Fouling in Direct Injection Spark Ignition Engines - A New Test Procedure for the Evaluation of Gasoline Additives, "SAE Technical Paper 2017-01-2294). Advances in fuel additive technology have made it possible to tackle this problem. So-called detergent additives used in fuels have already been proposed to keep the engine clean by limiting deposits ("keep-clean" effect) or by reducing deposits already present. in the internal parts of the combustion engine (“clean-up” effect in English). Mention may be made, by way of example, of document US Pat. No. 4,171959 which describes a detergent additive for gasoline fuel containing a quaternary ammonium function.

Nevertheless, engine technology is constantly evolving and fuel requirements must evolve to cope with these technological advances in combustion engines.

In particular, the new gasoline direct injection systems expose the injectors to more severe pressure and temperature conditions, which favors the formation of deposits.

In addition, these new injection systems have more complex geometries to optimize spraying, in particular, more holes having smaller diameters but which, on the other hand, induce a greater sensitivity to deposits. The presence of deposits can alter combustion performance, in particular increase pollutant emissions and particulate emissions.

Other consequences of the excessive presence of deposits have been reported in the literature, such as increased fuel consumption, and therefore particulate emissions, and driveability problems. .

The prevention and reduction of deposits in these new engines is essential for the optimal functioning of today's engines. There is therefore a need to provide detergent fuel additives promoting optimal operation of combustion engines, in particular, for new engine technologies but also older / conventional engine technologies.

In the case of positive-ignition engines (or gasoline engines) with indirect injection, a particular problem arises, linked to the formation of deposits on the external parts of the engine and in particular on the stems of the intake valves of the fuel mixture. air and fuel upstream of the combustion chamber, which results in a valve sticking phenomenon.

This phenomenon, well known to specialists under the English term of “valve sticking”, is described in a reference publication by Seppo Mikkonen, Reino Karlsson and Jouni Kivi entitled “Intake Valve Stiking in Some Carburetor Engines”, SAE Technical Paper Series no.881643, International Fuels and Lubricants Meeting and Exposition, Portland, Oregon, October 10-13, 1988. This phenomenon is caused, during operation of the engine at low temperature (in cold weather for example), by an accumulation of deposits with a high viscosity at the interface between the inlet valve stem and the valve guide, in the indirect injection positive-ignition engines. The accumulation of such deposits on the valve stems impedes movement of the latter, the stems stick to the valve guides, which causes improper valve closure, causes sealing problems in the combustion chamber, and may affect importantly the operation of the engine, and in particular can prevent it from starting in cold weather.

In general, there are different types of deposits on the intake valves of indirect injection spark ignition engines. These types of deposits are well known to engine manufacturers, and the occurrence of some is dependent on the treatment solutions of others.

On the one hand, a first type of deposit consists of those which form at high temperature on the intake valves of spark-ignition engines with indirect injection when using a fuel which does not contain any carbonate additive. detergency. These deposits consist in particular of carbonaceous residues associated with the phenomenon of coking (“coking” in English) and can also include deposits of the soap and / or varnish type (in English “lacquering”). These deposits are generally treated by the use of a detergent additive added to the fuel (additive fuel).

On the other hand, a second type of deposit consists of the viscous deposits, mentioned previously, which form at low temperature and appear on the intake valves of spark ignition engines with indirect injection when using additive fuels, thus causing the valve sticking phenomenon described above.

Thus, fuel additivation for the treatment and prevention of deposits that form at high temperatures can cause viscous deposits to appear at low temperatures.

As explained in the aforementioned publication (SAE Technical Paper Series No. 881643), the composition of gasoline and the additives it contains have a very significant influence on the valve sticking phenomena. In particular, the detergency additives conventionally incorporated in gasolines to preserve the cleanliness of the valves have paradoxically been found to promote phenomena of sticking thereof. In a manner known per se, the problem of valve sticking does not occur or very little when using a fuel devoid of carbon additives. detergency. In addition, the aforementioned publication shows that additives of polymeric type, capable of being used in gasoline and / or engine oils, are known as being agents for promoting valve sticking.

WO2006135881 describes a detergent additive containing a quaternary ammonium salt used to reduce or clean deposits in particular on the intake valves.

The solutions proposed in the prior art are not completely satisfactory. There is therefore a need to provide fuel additives which promote optimal operation of spark ignition engines, and which are effective in preventing all types of deposits, including on the intake valves.

There is also a need for a universal detergent additive capable of acting on deposits whatever the technology of the engine (direct or indirect injection) and / or the properties of the fuel, while minimizing the rate of treatment. state the quantities of additive (s) used.

OBJECT OF THE INVENTION

The Applicant has discovered that the use of a fuel composition comprising at least three additives, as described below, has remarkable and unexpected detergency properties for internal combustion engines, preferably gasoline, known under the name spark ignition engines. This combination of additives guarantees and improves the detergent power of fuels intended for internal combustion engines. It also produces an unexpected synergistic effect.

The additional advantages of the fuel additive composition used according to the invention are:

- protection of pumps, injection systems, the area of pistons, rings, liners and all moving parts with which this additive comes into contact in an engine,

- optimum engine operation,

- reduced fuel consumption,

- savings due to less engine maintenance and lower consumption,

- a reduction in particulate emissions,

- efficiency in direct injection and indirect petrol injection. A subject of the present invention is thus the use, for reducing and / or preventing deposits in the internal parts of a spark-ignition engine, of a fuel composition comprising:

(1) at least a first additive consisting of a quaternary ammonium salt,

(2) at least one second additive consisting of a non-quaternary polyisobutylene succinimide,

(3) at least a third additive, different from additives (1) and (2), consisting of a Mannich base, and in which the mass ratio of the amount of the first additive to the amount of the second additive is included in the range from 0.2: 1 to 2.5: 1.

Preferably, the mass ratio of the amount of the first additive to the amount of the second additive in the composition is in the range ranging from 1: 1 to 2: 1, and preferably ranging from 1.25: 1 to 1.5. : 1.

A subject of the invention is also the use of the composition, to maintain cleanliness (keep-clean effect) and / or clean (clean-up effect) the deposits in the internal parts of a spark-ignition engine, chosen from among the following: the combustion chamber and the fuel injection system, and preferably the fuel injection system.

A further subject of the invention is the use, to improve the detergency properties of a gasoline fuel, of a fuel concentrate comprising at least the above three additives, mixed with an organic liquid, said organic liquid. being inert with respect to the first, second and third additives, and miscible with said fuel.

The invention also relates to a method of maintaining the cleanliness and / or cleaning of at least one of the internal parts of a spark ignition engine (or internal combustion gasoline engine), comprising at least the following steps:

- the preparation of a fuel composition by additivation of a fuel with at least the three additives defined above, or a concentrate comprising them, then the combustion of said fuel composition in said spark ignition engine.

Other objects, characteristics, aspects and advantages of the invention will emerge even more clearly on reading the description which follows.

In what follows, and unless otherwise indicated, the limits of a domain of values are included in this domain, in particular in the expressions “comprised between” and “ranging / goes / extends from ... to ... ”. Furthermore, the expressions “at least one” and “at least” used in the present description are respectively equivalent to the expressions “one or more” and “greater than or equal”.

Finally, in a manner known per se, the term “CN compound or group” denotes a compound or a group containing in its chemical structure N carbon atoms.

DETAILED DESCRIPTION

The first additive: quaternary ammonium

The composition according to the invention comprises a first additive consisting of a quaternary ammonium salt, obtained, in a first embodiment, by reaction with a quaternization agent of a nitrogen compound comprising a tertiary amine function, this nitrogen compound. being the reaction product of an acylating agent substituted with a hydrocarbon group and of a compound comprising at least one tertiary amine group and at least one group chosen from primary amines, secondary amines and alcohols.

In a second embodiment, the quaternary ammonium salt is chosen from quaternized PIBA (polyisobutylene-amine) compounds, or from quaternized polyether-amines.

According to the first embodiment, which is preferred, said nitrogenous compound is the product of the reaction of an acylating agent substituted with a hydrocarbon group and of a compound comprising both an oxygen atom or a d atom. nitrogen capable of condensing with said acylating agent (that is to say that this compound comprises at least one group chosen from primary amines, secondary amines and alcohols) and a tertiary amine group.

The acylating agent is advantageously chosen from mono-or poly-carboxylic acids and their derivatives, in particular their ester, amide or anhydride derivatives. The acylating agent is preferably chosen from succinic, phthalic and propionic acids and the corresponding anhydrides.

In this embodiment, the acylating agent is substituted by a hydrocarbon group. The term "hydrocarbon" group is understood to mean any group having a carbon atom directly attached to the rest of the molecule (ie to the acylating agent) and having mainly an aliphatic hydrocarbon character. Hydrocarbon groups according to the invention can also contain non-hydrocarbon groups. For example, they can contain up to one non-hydrocarbon group per ten carbon atoms provided that the non-hydrocarbon group does not significantly modify the predominantly hydrocarbon character of the group. By way of example of such groups which are well known to those skilled in the art, mention may be made of hydroxyl groups, halogens (in particular chloro- and fluoro- groups), alkoxy, alkylmercapto and alkyl sulfoxy groups.

In one embodiment, preferably the hydrocarbon substituents do not contain such non-hydrocarbon groups and are purely aliphatic hydrocarbons.

The hydrocarbon substituent of the acylating agent preferably comprises at least 8, preferably at least 12 carbon atoms. Said hydrocarbon substituent may comprise up to about 200 carbon atoms.

The hydrocarbon substituent of the acylating agent preferably has a number average molecular weight (Mn) of between 160 to 2800, for example between 250 to 2000, more preferably between 500 to 1500 and, even more preferably between de 500 to 1300. A range of value of M _n between 700 and 1300 is particularly preferred, for example from 700 to 1200.

By way of example of hydrocarbon groups substituting the acylating agent, mention may be made of n-octyl, n-decyl, n-dodecyl, tetrapropenyl, n-octadecyl, oleyl, octadecyl or triacontyl groups.

The hydrocarbon substituent of the acylating agent can also be obtained from homo- or inter-polymers (for example copolymers, terpolymers) of mono- and di-olefins having from 2 to 10 carbon atoms, for example from ethylene, propylene, 1 -butene, isobutene, butadiene, isoprene, 1-hexene or 1-octene. Preferably, these olefins are 1-mono-olefins.

The hydrocarbon substituent of the acylating agent can also be chosen from derivatives of halogenated analogues (for example chlorinated or brominated) of these homopolymers or inter-polymers.

Alternatively, the hydrocarbon substituent of the acylating agent can be obtained from other sources, for example from high molecular weight alkenes monomers (eg, 1 -tetracontene) and their chlorinated analogues or hydrochlorinated, aliphatic petroleum fractions, for example paraffin waxes, their cracked, chlorinated and / or analogues thereof hydrochlorides, white oils, synthetic alkenes, for example produced by the Ziegler-Natta process (for example polyethylene fats) and other sources known to those skilled in the art.

Any unsaturation present in the hydrocarbon group of the acylating agent can optionally be reduced or eliminated by hydrogenation according to any known process.

The hydrocarbon substituent of the acylating agent is preferably substantially saturated, i.e., it does not contain more than one carbon-to-carbon unsaturated bond for each slice of ten carbon-to-carbon single bonds. present.

The hydrocarbon substituent of the acylating agent advantageously contains no more than one non-aromatic carbon-to-carbon unsaturated bond per every 50 carbon-to-carbon bonds present.

According to a preferred embodiment, the hydrocarbon substituent of the acylating agent is a polyisobutene group also called polyisobutylene (PIB). Very particularly preferred are the so-called highly reactive polyisobutenes (PIB). Highly reactive polyisobutenes (PIB) are understood to mean polyisobutenes (PIB) in which at least 50 mol%, preferably at least 70 mol% or more, of the terminal olefinic double bonds are of the vinylidene type as described in document EP0565285. In particular, preferred PIBs are those having more than 80 mole% and up to 100 mole% of vinylidene end groups as described in EP 1344785.

According to a particularly preferred embodiment, the acylating agent substituted with a hydrocarbon group is a polyisobutenyl succinic anhydride (PIB SA).

The preparation of polyisobutenyl succinic anhydrides is known per se, and widely described in the literature. Mention may be made, by way of example, of the processes comprising the reaction between polyisobutenes (PIB) and maleic anhydride described in documents US3361673 and US3018250 or the process comprising the reaction of a halogenated polyisobutene (PIB), in particular chlorinated , with maleic anhydride (US3172892).

Alternatively, polyisobutenyl succinic anhydride can be prepared by mixing a polyolefin with maleic anhydride and then passing chlorine through the mixture (GB949981).

Other hydrocarbon groups comprising an internal olefin, for example such as those described in application WO2007 / 015080, can also be used as a substituent for the acylating agent. We hear By internal olefin, any olefin containing predominantly one non-alpha double bond, which is a beta or higher position olefin.

Preferably, these materials are essentially beta-olefins or higher position olefins, for example containing less than 10% by mass of alpha-olefin, advantageously less than 5% by mass or less than 2% by mass.

Internal olefins can be prepared by isomerization of alpha-olefins according to any known process.

The compound comprising both an oxygen atom or a nitrogen atom capable of condensing with the acylating agent and a tertiary amine group can, for example, be chosen from the group consisting of: dimethylaminopropylamine, N, N-diethylaminopropylamine, N, N- dimethylamino-ethylamine, N, N-dimethyl-amino ethylamine ethylenediamine, 1,2-propylenediamine, 1, 3-propylene diamine, butylenediamines (isomers), diethylenetriamine, dipropylenetriamine, dibutylenetriamine, triethylenetetraamine, teraethylenepentaamine, pentaethylenehexaamine, hexamethylenetetramine, bis (hexametliylene) triamine, diaminobenzenes, and the pentanediamines, hexanediamines, Nyopamine, and preferably heptanediamines, Nyopanediamines, and heptanediamines, Nyopanediamines, and heptanediamines, Nyopamine, and heptanediamines.

Said compound can also be chosen from heterocyclic compounds substituted by alkylamines such as l - (3- aminopropyl) -imidazole, 4- (3-aminopropyl) morpholine, l- (2-aminoethyl) piperidine, 3 , 3-diamino-N-methyldipropylamine, diaminopyridines, and 3'3-bisamino (N, N-dimethylpropylamine).

The compound comprising both an oxygen atom or a nitrogen atom capable of condensing with the acylating agent and a tertiary amine group can also be selected from alkanolamines, including, but not limited to. , triethanolamine, trimethanolamine, N, N-dimethylaminopropanol, N, N-dimethylaminoethanol, N, N- diethylaminopropanol, N, N-diethylaminoethanol, N, N- diethylaminobutanol, N, N, N-tris (hydroxyethyl ) amine, N, N, N- tris (hydroxymethyl) amine, laN, N, N tris (aminoethyl) amine, N, N- dibutylaminopropylamine and N, N, N'-trimethyl-N'-hydroxyethyl- bisaminoethyl ether , N, N-bis (3-dimethylamino-propyl) -N- isopropanolamine, N- (3-dimethylamino-propyl) -N, N- diisopropanol amine, N '- (3- (Dimethylamino) propyl) - N, N-dimethyl-1,3-propanediamine; 2- (2-dimethylaminoethoxy) ethanol and N, N, N '- trimethylaminoethylethanolamine, or mixtures thereof. According to a preferred embodiment, said compound comprising at least one tertiary amine group and at least one group chosen from primary amines, secondary amines and alcohols is chosen from the following amines of formula (I) or (II):

(II) in which:

R6 and R7 are the same or different and represent, independently of each other, an alkyl group having 1 to 22 carbon atoms, preferably having 1 to 5 carbon atoms;

X is an alkylene group having 1 to 20 carbon atoms, preferably 1 to 5 carbon atoms; m is an integer between 1 and 5; n is an integer between 0 and 20; and

R8 is a hydrogen atom or a C1 to C22 alkyl group.

Said compound is preferably chosen from amines of formula

(I).

When the nitrogen compound comprises an amine of formula (I), R8 is preferably a hydrogen atom or an alkyl C l -C _16, preferably an alkyl group of Cl to _CIO, more preferably an alkyl group C l to C6.

R8 can, for example, be selected from the group consisting of hydrogen, methyl, ethyl, propyl, butyl and their isomers. Preferably R8 is a hydrogen atom.

When the nitrogenous compound comprises an amine of formula (II), m is preferably equal to 2 or 3, more preferably equal to 2; n is preferably an integer between 0 to 15, more preferably between 0 to 10, even more preferably between 0 to 5. Advantageously, n is 0.

According to a preferred embodiment, said nitrogenous compound is the product of the reaction of the acylating agent substituted with a hydrocarbon group and of a diamine of formula (I).

In this embodiment, preferably:

- R6 and R7 represent, independently of one another, a group C1 to C16 alkyl _, preferably a C1 to C10 alkyl group;

- R6 and R7 represent, independently of one another, a methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl group or their isomers. Advantageously, R6 and R7 represent, independently of one another, a C1 to C4 group, preferably a methyl group;

- X represents an alkylene group having 1 to 16 carbon atoms, preferably from 1 to 12 carbon atoms, more preferably from 1 to 8 carbon atoms, for example from 2 to 6 carbon atoms or from 2 to 5 carbon atoms. carbon. X particularly preferably represents an ethylene, propylene or butylene group, in particular a propylene group.

According to a particularly preferred embodiment, the nitrogenous compound is the reaction product of a succinic acid derivative substituted with a hydrocarbon group, preferably a polyisobutenyl succinic anhydride, and of an alcohol or of an amine also comprising a tertiary amine group, in particular a compound of formula (I) or (II) as described above and more preferably a compound of formula (I).

According to a first variant, the succinic acid derivative substituted with a hydrocarbon group reacts with the amine also comprising a tertiary amine group under certain conditions to form a succinimide (closed form). The reaction of the succinic acid derivative and the amine can also result under certain conditions in a succinamide, that is to say, a compound comprising an amide group and a carboxylic acid group (open form).

According to a second variant, an alcohol also comprising a tertiary amine group reacts with the succinic acid derivative to form an ester also comprising a free carboxyl group —CO2H (open form). Thus, in certain embodiments the nitrogenous compound may be the reaction product of a succinic acid derivative and an amine or an alcohol which is an ester or an amide and which further also comprises a carboxyl group -CO 2 H unreacted (open form).

The quaternary ammonium salt forming the first additive according to the present invention is obtained directly by reaction between the nitrogenous compound described above comprising a tertiary amine function and a quaternization agent.

According to a particular embodiment, the quaternization agent is chosen from the group constituting dialkyl sulphates, carboxylic acid esters, alkyl halides, benzyl halides, hydrocarbon carbonates, and hydrocarbon epoxides. optionally as a mixture with an acid, alone or as a mixture, preferably the carboxylic acid esters.

In fuel compositions, it is often desirable to reduce the content of halogen, sulfur and phosphorus-containing compounds.

Thus, if a quaternizing agent containing such an element is used, it may be advantageous to perform a subsequent reaction to exchange the counterion. For example, a quaternary ammonium salt formed by reaction with an alkyl halide can then be reacted with sodium hydroxide and the sodium halide salt removed by filtration.

The quaternizing agent can include halides such as chloride, iodide or bromide; hydroxides; sulfonates; bisulfites; alkyl sulphates such as dimethyl sulphate; sulfones; phosphates; C1-C12 alkylphosphates _; C1-C12 dialkylphosphates; borates; C 1-C12 alkylborates; nitrites; nitrates; carbonates; bicarbonates; alkanoates; C 1 -C 12 0,0-dialkyldithiophosphates _, alone or as a mixture.

According to a particular embodiment, the quaternization agent can be chosen from derivatives of dialkylsulphates such as dimethyl sulphate, of N-oxides, of sulphones such as propane- and butanesulfone, of alkyl halides. , acyl or aralkyl such as methyl and ethyl chloride, benzyl bromide, iodide or chloride, and hydrocarbon carbonates (or alkylcarbonates).

If the acyl halide is benzyl chloride, the aromatic ring is optionally substituted by one or more alkyl or alkenyl groups.

The hydrocarbon (alkyl) groups of the hydrocarbon carbonates can contain from 1 to 50, from 1 to 20, from 1 to 10 or from 1 to 5 carbon atoms per group. According to one embodiment, the hydrocarbon carbonates contain two hydrocarbon groups which may be identical or different. By way of example of hydrocarbon carbonates, mention may be made of dimethyl or diethyl carbonate.

According to a preferred embodiment, the quaternization agent is chosen from the hydrocarbon epoxides represented by the following formula (III): in which R9, R10, R11 and R12 may be the same or different and represent, independently of each other, a hydrogen atom or a C 1 -C 50 hydrocarbon group _. By way of nonlimiting example, mention may be made of styrene oxide, ethylene oxide, propylene oxide, butylene oxide, stilbene oxide and C 1 to C 50 epoxides _. Styrene oxide and propylene oxide are particularly preferred, and more preferably the quaternizing agent is propylene oxide.

Such hydrocarbon epoxides can be used as a quaternizing agent in combination with an acid, for example with acetic acid. The hydrocarbon epoxides can also be used alone as a quaternization agent, in particular without additional acid.

Without being bound by this hypothesis, it would seem that the presence of the carboxylic acid function in the molecule promotes the formation of the quaternary ammonium salt. In such an embodiment not using additional acid, a protic solvent is used for the preparation of the quaternary ammonium salt. For example, protic solvents such as water, alcohols (including polyhydric alcohols) can be used alone or as a mixture. Preferred protic solvents have a dielectric constant greater than 9.

Corresponding quaternary ammonium salts prepared from amides or esters and derivatives of succinic acid are described in WO2010 / 132259 or in EP1896555.

According to another embodiment, the quaternization agent is chosen from the compounds of formula (IV):

wherein R13 is an optionally substituted alkyl, alkenyl, aryl and aralkyl group, and R14 is a C1 to C22 alkyl, aryl or alkylaryl group.

The compound of formula (IV) is a carboxylic acid ester capable of reacting with a tertiary amine to form a quaternary ammonium salt. Compounds of formula (IV) are selected, for example, from esters of carboxylic acids having a pKa of 3.5 or less. The compound of formula (IV) is preferably chosen from esters of substituted aromatic carboxylic acid, of alpha-hydroxycarboxylic acid and of polycarboxylic acid.

According to one embodiment, the ester is a substituted aromatic carboxylic acid ester of formula (IV) in which R13 is a substituted aryl group. Preferably, R13 is a substituted aryl group having 6 to 10 carbon atoms, preferably a phenyl or naphthyl group, more preferably a phenyl group. R13 is advantageously substituted with one or more groups chosen from the carboalkoxy, nitro, cyano, hydroxy, SR15 and NR15R16 radicals. Each of the groups R15 and Rm can be a hydrogen atom or an optionally substituted alkyl, alkenyl, aryl or carboalkoxy group. Each of the groups R15 and Ri ₆ represents, advantageously, the hydrogen atom or an optionally substituted C 1 to C22 alkyl group, preferably the hydrogen atom or a C 1 to C16 alkyl group _, more preferably 1 hydrogen _{atom or a C1 to C4 alkyl group,} even more preferably the hydrogen atom or a C1 to C4 alkyl group. R15 is preferably a hydrogen atom and R 1 ₆ a hydrogen atom or a C1 to C4 group. Advantageously, R15 and Ri ₆ are both hydrogen.

According to one embodiment, R13 is an aryl group substituted by one or more groups chosen from hydroxyl, carboalkoxy, nitro, cyano and NH2 radicals. R13 can be a polysubstituted aryl group, for example trihydroxyphenyl. Advantageously, R13 is a monosubstituted aryl group, preferably ortho substituted. R13 is, for example, substituted by a group chosen from the OH, NH2, NO2 or COOMe radicals, preferably OH or NH2. R13 is preferably a hydroxy-aryl group, in particular 2-hydroxyphenyl.

According to a particular embodiment, R14 is an alkyl or alkylaryl group. R14 can be a C 1 to C16 _, preferably C 1 to C10, advantageously C 1 to C8 alkyl group. R14 may be a C 1 to C16, preferably C 1 to Cio _, advantageously C 1 to C8 alkylaryl group. R14 can for example be chosen from methyl, ethyl, propyl, butyl, pentyl, benzyl or their isomers. Preferably, R14 is a benzyl or methyl group, more preferably methyl.

A particularly preferred compound is methyl salicylate.

According to a particular embodiment, the compound of formula (IV) is an ester of an alpha-hydroxycarboxylic acid corresponding to the formula (V) following:

wherein R17 and R18 are the same or different and are independently selected from the group consisting of the hydrogen atom, alkyl, alkenyl, aryl or aralkyl groups. Such compounds are for example described in document EP 1254889.

Examples of compounds of formula (IV) in which R13COO is the residue of an alpha-hydroxycarboxylic acid include methyl-, ethyl-, propyl-, butyl-, pentyl-, hexyl-, phenyl-, benzyl- or allyl- 2-hydroxy-isobutyric acid esters; methyl-, ethyl-, propyl-, butyl-, pentyl-, hexyl-, benzyl-, phenyl- or allyl-esters of 2-hydroxy-2-methylbutyric acid; 2-hydroxy-2-ethylbutyric acid methyl-, ethyl-, propyl-, butyl-, pentyl-, hexyl-, benzyl-, phenyl- or allyl-esters; methyl-, ethyl-, propyl-, butyl-, pentyl-, hexyl-, benzyl-, phenyl- or allyl- esters of lactic acid and methyl-, ethyl-, propyl-, butyl-, pentyl-, hexyl -, allyl-, benzyl- or phenyl-esters of glycolic acid. From the above, the preferred compound is methyl-2-hydroxyisobutyrate.

According to a particular embodiment, the compound of formula (IV) is an ester of a polycarboxylic acid chosen from dicarboxylic acids and carboxylic acids having more than two acid functions. The carboxylic functions are preferably all in esterified form. Preferred esters are C 1-4 alkyl esters.

The compound of formula (IV) can be chosen from oxalic acid diesters, phthalic acid diesters, maleic acid diesters, malonic acid diesters or citric acid diesters. Preferably, the compound of formula (IV) is dimethyl oxalate.

According to a preferred variant, the compound of formula (IV) is a carboxylic acid ester having a pKa of less than 3.5. For cases where the compound comprises more than one acidic group, reference will be made to the first dissociation constant.

The compound of formula (IV) can be chosen from one or more carboxylic acid esters chosen from oxalic acid, phthalic acid, salicylic acid, maleic acid, malonic acid, citric acid. , nitrobenzoic acid, aminobenzoic acid and 2,4,6-acid trihydroxybenzoic acid. Preferred compounds of formula (IV) are dimethyl oxalate, methyl 2-nitrobenzoate and methyl salicylate.

According to a particularly preferred embodiment, the quaternary ammonium salt used in the invention is formed by reaction of a hydrocarbon epoxide, preferably chosen from those of formula (III) above and more preferably propylene oxide. , with the reaction product of a polyisobutenyl succinic anhydride in which the polyisobutylene group (PIB) has a number-average molecular mass (Mn) of between 700 and 1000 and dimethyl-aminoprop y lamin.

According to a particularly preferred embodiment, the additive (1) is chosen from polyisobutylene succinimides functionalized with a quaternary ammonium group.

The composition according to the invention comprises the first additive (s) as described above in a preferential content ranging from 5 to 10,000 ppm by weight, preferably from 5 to 1000 ppm by weight, more preferably from 10 to 500 ppm by weight , more preferably from 15 to 200 ppm by weight, and better still from 20 to 150 ppm by weight, relative to the total weight of the fuel composition.

The second additive: polyisobutylene succinimide

The composition according to the invention comprises a second additive (2) consisting of a non-quaternary polyisobutylene succinimide, that is to say that it does not contain a quaternary ammonium group.

According to a preferred embodiment, said second additive results from the condensation: of a compound A consisting of a dicarboxylic acid substituted with a polyisobutylene group or of an anhydride of such a diacid, with a compound B consisting of a primary polyamine of general formula (VI) below:

H ₂ N - [- (CHRl - (CH ₂ ) _p -CHR2) _n -NH] _m -H (VI) in which RI and R2, identical or different, represent hydrogen or a hydrocarbon group comprising from 1 to 4 carbon atoms, n is an integer varying from 1 to 3, m is an integer varying from 1 to 10, preferably from 1 to 4; and p is an integer equal to 0 or 1.

In a preferred embodiment, said additive (2) is obtained by condensation of compound A with compound B, used in amounts such that the molar ratio A / B is in the range going from 1: 1 to 1: 3 . Preferably, the molar ratio A / B is included in the range going from 1: 1, 1 to 1: 2, even more preferably the molar ratio A / B is included in the range going from 1: 1, 1 to 1: 1, 5.

Said additive (2) can in particular be obtained by condensation of 60 to 90% by weight of compound A, and from 10 to 30% by weight of compound B.

The average molar mass of the compounds A according to the present invention varies from 200 to 3000, preferably from 200 to 2000 g / mol, preferably from 200 to 1500 g / mol, even more preferably from 900 to 1300 g / mol. These compounds are well known from the prior art.

Among the primary polyamines according to formula (VI), the polyamines of the group consisting of diethylene triamine, dipropylene triamine, triethylene tetramine, tetraethylene pentamine and their substituted derivatives, or mixtures thereof, are preferred.

The mixing of these compounds A and B can be done either in the order detailed below, or in a different order.

In a preferred mode, the compound B, that is to say the primary polyamine of formula (VI) is added to the compound A, that is to say the acid (s) carboxylic hydrocarbon (s) ( s) or anhydride (s).

Polyamine B is gradually added in an organic solvent, then to the solution of the mixture of carboxylic hydrocarbons at room temperature, the mixture is then heated between 65 and 250 ° C, and preferably between 80 and 220 ° C, for from 5 to 30 hours.

The organic solvent necessary for the solubilization of the primary polyamine is chosen with a boiling point of between 65 and 250 ° C, and preferably between 80 and 220 ° C, and its capacity to eliminate the water formed by condensation of the polyamine on compound A by azeotropic distillation of the water / solvent mixture. The solvent is chosen from the group consisting of benzene, toluene, xylenes, ethylbenzene and commercial cuts of hydrocarbons, for example those distilling at 190 to 209 ° C. and containing 99% by weight of aromatic compounds.

According to another embodiment of the invention, a mixture of solvents can be used and in particular a mixture of xylenes, or else a xylene / alcohol mixture, preferably the alcohol is ethyl-2-hexanol for a on the one hand, to facilitate the homogeneity of the medium and, on the other hand, to promote the kinetics of the reaction.

After the end of the addition of the primary polyamine B, the heating is maintained under reflux until the complete elimination of the water, for 0.5 to 7 hours, preferably 1 to 5 hours. In one embodiment, the composition according to the invention comprises the second additive (s) as described above in a preferential content ranging from 5 to 10,000 ppm by weight, preferably from 5 to 1000 ppm by weight, more preferably from 10 to 500 ppm by weight, more preferably from 15 to 200 ppm by weight, and better still from 20 to 150 ppm by weight, relative to the total weight of the fuel composition.

The third additive: Mannich base

The fuel composition according to the invention comprises a third additive (3), different from additives (1) and (2), consisting of a Mannich base. The preparation of Mannich bases is known per se, and for example described in documents US2008 / 0052985, or US8016898.

The third additive is advantageously prepared by reacting a phenol substituted with a hydrocarbon group, an aldehyde and an amine.

The hydrocarbon substituent of said phenol may contain from 6 to 400 carbon atoms, advantageously from 30 to 180 carbon atoms, preferably from 10 to 110, better still from 40 to 110 carbon atoms.

The hydrocarbon substituent of said phenol can be derived from an olefin or a polyolefin. By way of example, mention may be made of alpha-olefins such as n-1-decene. Preferably, the hydrocarbon substituent of said phenol is a polyisobutylene group.

The polyolefins forming the hydrocarbon substituent of the phenol can be prepared by polymerization of olefin monomers according to any known polymerization process.

Advantageously, the polyolefins are chosen from polyisobutylenes having a number-average molar mass (Mn) of between 400 to 3000, preferably between 400 to 2500, more preferably between 400 and 1500, between 500 to 1500 or between 500 and 1000.

Polyisobutylene is preferably very reactive, which differs from poorly reactive polyisobutylenes by their small amount of terminal ethylene double bonds. The reactive polyisobutylenes according to the invention are composed of at least 85% by weight, preferably at least 90% by weight, preferably at least 95% by weight of isobutene units.

Preferably, the polyisobutylenes, preferably very reactive, have a polydispersity of less than 1.9, preferably less than 1.7 and even more preferably less than 1.5, the polydispersity being the quotient the mass-average molar mass Mw and the number-average molar mass Mn.

The phenol substituted with a hydrocarbon group can be prepared by alkylation of phenol with an olefin or polyolefin described above, such as polyisobutylene or polypropylene, preferably polyisobutylene, using conventional alkylation methods.

According to one variant, the phenol can be substituted by one or more low molecular weight alkyl groups, for example a phenol carrying one or more alkyl chains of less than 28 carbon atoms, preferably of less than 24 carbon atoms, more preferably of less than 20 carbon atoms, even more preferably less than 18 carbon atoms, even more preferably 16 carbon atoms and even more preferably 14 carbon atoms.

Preference will be given to a monoalkylic phenol having from 4 to 20 carbon atoms, preferably from 6 to 18, more preferably from 8 to 16, even more preferably from 10 to 14 carbon atoms, for example a phenol substituted by an alkyl group in C 12.

The aldehyde used to form the product of the Mannich reaction can consist of 1 to 10 carbon atoms, and is generally formaldehyde or its reactive equivalents such as formalin (methyl alcohol and formaldehyde), trioxanes, or para. formaldehyde, and preferably para-formaldehyde.

The amine used to form the Mannich reaction product can be a monoamine or a polyamine.

By way of nonlimiting examples, mention may be made, as monoamines, of ethylamine, dimethylamine, diethylamine, di-n-propylamine, di-isopropylamine, n-butylamine, dibutylamine, allylamine, isobutylamine. , cocoamine, stearylamine, laurylamine, methyllaurylamine, oleylamine, N-methyl-octylamine, dodecylamine, diethanolamine, morpholine, dimethylmorpholine, dicyclohexylamine, pyrrolidine, piperidine, diethylenetriamine, triethyl N, N-diethylethylenediamine, N, N, N ', N'-tetramethyldiethylenetriamine, polyethyleneimines and octadecylamine. The polyamines are chosen from compounds comprising two or more amino groups.

By way of nonlimiting examples, mention may be made, as polyamines, of polyalkylene polyamines in which the alkylene group has, for example, from 1 to 6, preferably from 1 to 4, more preferably from 2 to 3 carbon atoms. The preferred polyamines are polyethylene- polyamines. The polyamine can comprise 2 to 15 nitrogen atoms, preferably 2 to 10 nitrogen atoms, preferably 2 to 8 nitrogen atoms. Examples of polyamines are: 3- (dimethylamino) -n-propylamine, di [3- (dimethylamino) -n-propyl] amine, di [3- (diethylamino) -n-propyl] amine, di [ 2- (dimethylamino) ethyl] amine, N-methylpiperazine,

According to one variant, the amine used to form the Mannich reaction product comprises a diamine, preferably which comprises a primary or secondary amine function taking part in the Mannich reaction and a tertiary amine function.

According to another variant, the additive (3) can be obtained by a Mannich reaction and then subjected to a reaction making it possible to obtain a tertiary amine function; for example, a process using an intermediate compound comprising a secondary amine and obtained by Mannich reaction, which is then modified, for example by alkylation to produce a tertiary amine.

According to one embodiment, the content of the additive (3) ranges from 5 to 10,000 ppm by weight, preferably from 5 to 1000 ppm by weight, more preferably from 50 to 500 ppm by weight, more preferably from 100 to. 500 ppm by weight, and more preferably 150 to 450 ppm by weight, relative to the total weight of the fuel composition.

Fuel concentrate

The present invention also relates to the use, to improve the detergency properties of a gasoline fuel, of a fuel concentrate comprising at least the additives (1), (2) and (3), as defined herein. above, mixed with an organic liquid, said organic liquid being inert with respect to the first, second and third additives, and miscible with said fuel.

The organic liquid is advantageously miscible with liquid fuels, in particular those obtained from one or more sources chosen from the group consisting of mineral, preferably petroleum, animal, vegetable and synthetic sources. The term “miscible” is understood to mean the fact that the additives and the organic liquid form a solution or a dispersion so as to facilitate the mixing of the additives according to the invention into liquid fuels according to conventional fuel additivation processes.

The organic liquid is preferably chosen from aromatic hydrocarbon solvents such as the solvent sold under the name “SOLVESSO”, alcohols, ethers and other oxygenated compounds, and paraffinic solvents such as hexane, pentane or isoparaffins, alone or as a mixture.

Fuel

The fuel according to the present invention contains a base resulting from one or more sources chosen from the group consisting of mineral, animal, vegetable and synthetic sources, and is preferably chosen from hydrocarbon fuels, non-essentially hydrocarbon fuels and theirs. mixtures

Oil will preferably be chosen as the mineral source.

The fuel is advantageously chosen from hydrocarbon-based fuels and non-essentially hydrocarbon-based fuels, alone or as a mixture.

The term “hydrocarbon fuel” is understood to mean a fuel consisting of one or more compounds consisting solely of carbon and hydrogen. Gasolines are hydrocarbon fuels.

The term “non-essentially hydrocarbon-based fuel” is understood to mean a fuel consisting of one or more compounds consisting not essentially of carbon and of hydrogen, that is to say which also contain other atoms, in particular oxygen atoms.

Hydrocarbon fuels include in particular light distillates having a boiling point in the gasoline range, preferably between 30 and 210 ° C.

These light distillates can, for example, be chosen from distillates obtained by direct distillation of crude hydrocarbons, vacuum distillates, hydrotreated distillates, distillates resulting from catalytic cracking and / or hydrocracking of vacuum distillates, distillates resulting from ARDS-type conversion processes (by desulphurization of atmospheric residue).

In other words, the hydrocarbon fuel is chosen from gasolines.

Gasolines include, in particular, any commercially available spark ignition engine fuel compositions. By way of representative example, mention may be made of the gasolines meeting standard NF EN 228. The gasolines generally have sufficiently high octane numbers to avoid the knocking phenomenon. Typically, gasoline-type fuels marketed in Europe, which comply with standard NF EN 228, have an engine octane number (MON in English "Motor Octane Number") greater than 85 and a research octane number (RON in English "Research Octane Number") of a minimum of 95. Gasoline type fuels have, generally, a RON ranging from 90 to 100 and a MON ranging from 80 to 90, the RON and MON being measured according to the standard ASTM D 2699-86 or D 2700-86.

Non-essentially hydrocarbon-based fuels include in particular oxygenates, for example distillates resulting from the BTL (in English “biomass to liquid”) conversion of plant and / or animal biomass, taken alone or in combination; biofuels, for example oils and / or esters of vegetable and / or animal oils; and bioethanols.

Mixtures of hydrocarbon fuel and non-essentially hydrocarbon fuel are typically gasolines of the Ex type.

By gasoline of type Ex for a spark ignition engine is meant a gasoline fuel which contains x% (v / v) of oxygenates, generally ethanol, bioethanol and / or ethyl-tertio-butyl-ether ( ETBE).

The fuel composition may comprise only new sources of distillates or be composed of a mixture with conventional petroleum lighter distillates as the gasoline-type fuel base.

Preferably, the content of each additive (1) and (2) in the fuel composition according to the invention ranges from 5 to 10,000 ppm by weight, preferably from 5 to 1000 ppm by weight, more preferably from 10 to 500 ppm by weight, more preferably from 15 to 200 ppm by weight, and better still from 20 to 150 ppm by weight, relative to the total weight of the fuel composition.

Preferably, the content of additive (3) in the fuel composition according to the invention ranges from 5 to 10,000 ppm by weight, preferably from 5 to 1000 ppm by weight, more preferably from 50 to 500 ppm by weight. , more preferably from 100 to 500 ppm by weight, and better still from 150 to 450 ppm by weight, relative to the total weight of the fuel composition.

Preferably, the sulfur content in the fuel composition is less than or equal to 1500 ppm by weight, preferably less than or equal to 1000 ppm by weight, preferably less than or equal to 500 ppm by weight and preferably less than or equal to 50 ppm by weight, even more preferably less than or equal to 10 ppm by weight, relative to the total weight of the composition, and advantageously without sulfur.

Other additives in the fuel composition

The fuel composition can also comprise one or more additional additive (s), different from said additives according to the invention. This or these additional additives can for example be chosen, in a nonlimiting manner, from: detergent additives, anti-corrosion agents, anti-oxidants, carrier oils, dispersants, demulsifiers, tracers or markers, reodorants, friction modifiers, lubricity additives or lubricity additives, combustion aids (catalytic combustion and soot promoters), anti-sedimentation agents, antiwear agents and agents modifying the conductivity.

This or these additional additives are more preferably chosen from: a) lubricating additives or anti-wear agents, in particular (but not limited to) chosen from the group consisting of fatty acids and their ester or amide derivatives, in particular glycerol monooleate, and derivatives of mono- and polycyclic carboxylic acids. Examples of such additives are given in the following documents: EP680506, EP860494,

WO98 / 04656, EP915944, FR2772783, FR2772784; b) detergent additives, in particular (but not limited to) chosen from polyetheramines; c) friction or friction modifiers in particular (but not limited to) chosen from the group consisting of acids or esters of fatty acids or mixtures of acids or esters of fatty acids, for example oleic and linoleic acids , resin, palmitic; or from fatty acid dimers, or mono or di-propoxylated esters; sorbitan esters; sucrose stearates; or from glycerol and its derivatives; or esters of pentaerythritol; or amines; and preferably chosen from esters of glycerol or polyglycerol, or acids or esters of fatty acids, or mixtures thereof; d) anticorrosion additives in particular (but not limited to) chosen from the group consisting of acids or esters of fatty acids or mixtures of acids or esters of fatty acids, or from dimers of fatty acids; e) antioxidants, in particular (but not limited to) chosen from the group consisting of 2,6-di-t-butyl-4-methyl phenol, t-butyl hydroquinone, 2,6 and 2,4 di -t-butyl phenol, 2,4-dimethyl-6-t-butyl phenol, pyrogallol, tocopherol, 4,4'-methylene bis (2,6-di-t-butyl phenol), alone or in mixed ; f) carrier oils in particular (but not limited to) chosen from the group consisting of poly-oxyalkylenes, such as, for example, poly-butene-oxide or poly-propene-oxide. These additional additives can be present in an amount ranging from 3 to 1000 ppm (each) by weight, relative to the total weight of the fuel composition, preferably from 5 to 500 ppm.

Uses

Another object of the invention is the use of the fuel composition to maintain cleanliness (keep-clean effect) and / or clean (clean-up effect) the deposits in the internal parts of an engine chosen from the following : the combustion chamber and the fuel injection system, and preferably the fuel injection system.

The composition according to the invention is effective in conventional engines; or more modern engines such as, IDE, BMW B48, Renault H5FT and HR13DDT, PSA EB2DTS, Volkswagen EA1 11 ...; and in IIE the Mercedes M102E and Ml 11E, PSA EW 10A and EB2 engines ...

Another object of the invention is the use of the fuel composition comprising at least a first additive, at least a second additive and at least a third additive defined above to prevent and / or reduce coking (i.e. i.e. coke deposits), particularly in direct petrol injection (IDE), and / or lacquering (i.e. soap and / or varnish deposits), particularly in indirect petrol injection (IIE), and in particular on the valves.

The invention thus makes it possible to prevent and / or reduce deposits of coke and / or soap on the fuel inlet valves in a spark-ignition engine with indirect injection

Another object of the invention is the use of the fuel composition comprising at least a first additive, at least a second additive and at least a third additive defined above to prevent and / or reduce sticking (or valve- sticking) of the fuel inlet valves in an engine, in particular a spark ignition engine with indirect gasoline injection (IIE). In this embodiment, said composition advantageously further comprises a fourth additive which is a carrier oil.

In the case of use for combating valve-sticking, the composition preferably further comprises a carrier oil. The carrier oil can be chosen from oils of poly (oxyalkylene) type, for example poly-butene oxide or poly-propene oxide. In one embodiment, the weight ratio of the amount of carrier oil to the amount of detergent additives is in the range of 0.1 to 2.5, preferably 0.3 to 1.5, even more preferably from 0.5 to 1. Another object of the invention is the use of said fuel composition for reducing the fuel consumption of the engine (“Fuel Eco” action) and / or minimizing the loss of power from said engine, and / or reducing pollutant emissions. , in particular, particulate emissions from the combustion engine.

Another object of the invention is the use of said composition of additives to reduce the fouling of the area of the pistons, segments, and liners of the engine, preferably of a gasoline direct injection engine (or IDE ).

The quaternary ammonium additive (1), as defined in the present invention, is particularly effective in combating piston fouling, especially in IDE.

The combination of additives (1) and (2) is also very effective in combating piston fouling, especially in IDE.

The fuel composition can be used in indirect gasoline injection (IIE) or in direct gasoline injection (IDE), preferably in IDE.

In one embodiment, the IDE is central, and in another embodiment, the IDE is lateral. The present invention is therefore effective and used in central and / or lateral IDE.

The fuel composition can also be used to combat corrosion in the engine. The polyisobutylene succinimide additive (2), as defined in the present invention, is particularly effective in combating corrosion.

The use according to the invention is applicable to engines used in light vehicles (light vehicles), heavy goods vehicles (PL), stationary vehicles, agricultural machinery, thermal vehicles or hybrid vehicles (rechargeable or not), engines dual-fuel gasoline / gas, for example gasoline / NGV (natural gas) or gasoline / LPG; gasoline / CNG or gasoline / LPG concomitant injection engines ...

The additive, fuel or concentrate composition can be used in "harsh" or "easier to process" gasolines. "Harsh" gasolines are distinguished from easy-to-process gasolines in that a harsh gasoline requires a higher additive compound processing rate to be effective than "easy-to-process" gasoline. One can mention as "severe" species the species similar to the reference species CEC RL12-09 and CEC RL-83.

Process (or method) for preparing the fuel composition The fuel composition according to the invention can be prepared according to any known process, by adding a liquid hydrocarbon cut as described above with at least the three additives as described above, and optionally one or more other additives other than those described above. additives according to the invention, as described above.

Process to improve engine cleanliness

The invention also relates to a method of maintaining the cleanliness and / or cleaning of at least one of the internal parts of a spark-ignition engine, comprising at least the following steps:

- the preparation of a fuel composition by additivation of a fuel with at least the three additives as described above or with a concentrate comprising them, then

the combustion of said fuel composition in said spark ignition engine.

All characteristics of additives, fuel or use are applicable to the process.

According to one variant, the above step of preparing a fuel composition is preceded by a preliminary step of determining the content of each of the three additives to be incorporated into said fuel composition in order to achieve a given specification relating to the properties. detergency of the fuel composition.

This preliminary step is common practice in the field of fuel additives and involves defining at least one characteristic representative of the detergency properties of the fuel composition as well as a target value.

Methods for evaluating the detergent properties of fuels have been widely described in the literature and are within the general knowledge of those skilled in the art. Mention will be made, by way of nonlimiting example, of the tests standardized or recognized by the profession or the methods described in the following literature, for engines by positive ignition with indirect injection:

- the Mercedes Benz M102E method, CEC F-05-A-93 standardized test method, and

- the Mercedes Benz M11 1E method, CEC F-20-A-98 standardized test method.

These methods make it possible to measure deposits on the intake valves (IVD), the tests generally being carried out on Eurosuper gasoline meeting the EN228 standard. For direct injection positive-ignition engines:

- the method described by the applicant in the article "Evaluating Injector Fouling in Direct Injection Spark Ignition Engines", Mathieu Arondel, Philippe China, Julien Gueit; Conventional and future energy for automobiles; 10th international colloquium; January 20-22, 2015, p.375-386 (Technische Akademie Esslingen by Techn. Akad. Esslingen, Ostfildern), for the evaluation of coking type deposits on the injector,

- the method described in document US20130104826, for the evaluation of coking type deposits on the injector,

- the VW EA 111 method under development within the framework of the CEC TDG- F- 113 based on the VW EA 111 engine (Glawar, A., et al., "Development of a Fuel System Cleanliness Test Method in a Euro 4 Direct-Injection Gasoline Engine (VW 1.4 L TSI 90 kW), "SAE Int. J. Fuels Lubr. 10 (3): 2017, doi: 10.4271 / 2017-01 -2296).

Mention may also be made of the CEC Ll l 1 - 16 method which makes it possible to assess the fouling of the area of the pistons, rings and liners of a gasoline direct injection engine.

The examples below are given by way of illustration of the invention, and should not be interpreted in such a way as to limit its scope.

EXAMPLES

The examples below were produced from an E gasoline, the characteristics of which are detailed in Table 1 below.

Table 1: characteristics of gasoline E

Fuel compositions were prepared by adding the following additives Al, A2 and A3 to gasoline E:

Al: quaternary ammonium salt, formed by reaction of propylene oxide with the condensation product of a polyisobutenyl succinic anhydride, the polyisobutylene group (PIB) of which has a number average molecular mass (Mn) of 1000 g / mol and dimethyl-aminopropylamine;

A2: polyisobutylene succinimide, obtained by condensation of a polyisobutenyl-succinic anhydride, the polyisobutylene group (PIB) of which has a number-average molecular mass (Mn) of 1000 g / mol and tetraethylenepentamine;

A3: Mannich base, obtained by reacting a phenol substituted with a polyisobutylene group (PIB) having a number average molecular mass (Mn) of 1000 g / mol, with formaldehyde and dimethyl-aminopropylamine.

The amount of additive added to each composition is detailed in Table 2 below, in which the content of each additive is indicated in ppm by weight relative to the total weight of the final composition:

Table 2: Fuel compositions from gasoline E

Composition El is in accordance with the invention. The compositions E2, E3 and E4 are comparative. The additivation rate is identical between the three compositions El, E2 and E3 (433 ppm).

The performance in terms of detergency of each of the Fuel compositions E1 to E4 above as well as the reference fuel E without additives were evaluated using a test making it possible to determine the level of fouling of the injectors of a gasoline direct injection engine (IDE).

The engine used is a motor EB2DTS PSA, which is a gas cylinder 3 1199 cm ³ turbocharged direct injection engine, with the injectors in a central position.

Before carrying out the test, the flow rate of the injectors is determined by means of a bench for measuring the flow rates of the EFS IFR 600 type injectors, which makes it possible in a manner known per se to measure the mass fuel flow rate of the injectors.

The principle of the test consists in making the engine run for 5 hours at 4300 revolutions / minute and 11 bars of mean effective pressure (hereinafter referred to as PME), by supplying it with the gasoline tested at a pressure of injection of 70 bars, after a heating period of 20 minutes, and a stabilization period of 10 minutes.

The test determines the average flow loss, defined as corresponding to the average restriction of the flow of gasoline emitted by the engine injectors at the end of the test. The higher the average flow loss, the more the fuel has a clogging effect on the engine's injectors, and the lower its detergent performance.

The test steps are as follows:

- A heating step;

- A stabilization stage;

- A fouling step;

- A step of determining the flow loss of the injectors.

The test conditions are as follows:

Temperatures:

- Water at motor outlet: 90 ± 2 ° C

- Oil: 110 ± 5 ° C

- Air in the intake manifold: 40 ± 2 ° C

- Low pressure loop fuel: 50 ± 2 ° C Fuel injection pressure: 70 bars

For the heating phase, the engine is subjected to a gradual increase in speed, for a period of 20 minutes, until reaching a speed of 4000 revolutions / minute and an PME of 8 bar.

For the stabilization phase, the engine is maintained under the operating conditions of the test, at a speed of 4300 revolutions / minute, at a PME of 11 bar and a fuel injection pressure of 70 bar, for a period of 10 minutes.

For the fouling phase, the engine then runs for 5 hours at 4300 rpm and 11 bar PME with a fuel injection pressure of 70 bar.

At the end of the test, the injectors are removed in order to be evaluated by means of the EFS IFR 600 injector flow rate measuring bench, which makes it possible to measure the mass fuel flow rate of the injectors at the end of the test. . By comparison with the value of the mass fuel flow of the injectors measured before the test, the average loss of flow of the injectors is calculated.

The results obtained are detailed in Table 3 below.

Table 3: results

The above results show that the composition E1 according to the invention containing the combination of the three additives A1, A2 and A3 leads to very good results in terms of reducing the fouling of the injectors (“keep clean” effect). . For a total additive content which is otherwise identical (433 ppm), these results are significantly better than those obtained with the comparative compositions E2 and E3 containing only two of the three additives. The results obtained with composition E4 containing only one of the three additives, and with the reference fuel E, are even worse.

These results illustrate the synergistic effects provided by the combination of the two additives according to the present invention.

Claims

1. Use, to reduce and / or prevent deposits in the internal parts of a spark-ignition engine, of a fuel composition comprising:

(1) at least a first additive consisting of a quaternary ammonium salt,

(2) at least one second additive consisting of a non-quaternary polyisobutylene succinimide,

(3) at least a third additive different from additives (1) and (2), consisting of a Mannich base, and in which the mass ratio of the amount of the first additive to the amount of the second additive is within the range ranging from 0.2: 1 to 2.5: 1.

2. Use according to claim 1, wherein the mass ratio of the amount of the first additive to the amount of the second additive is in the range from 1: 1 to 2: 1, and preferably from 1.25: 1 to 1, 5: 1.

3. Use according to claim 1 or 2, wherein the first additive (1) consisting of quaternary ammonium salt is obtained by reaction with a quaternization agent of a nitrogen compound comprising a tertiary amine function, this compound being the product. of the reaction of an acylating agent substituted with a hydrocarbon group and of a compound comprising at least one tertiary amine group and at least one group chosen from primary amines, secondary amines and alcohols.

4. Use according to claim 3, in which the acylating agent substituted with a hydrocarbon group is chosen from mono-or poly-carboxylic acids and their derivatives, in particular their ester, amide or anhydride derivatives, and preferably the. acylating agent is chosen from succinic, phthalic and propionic acids and the corresponding anhydrides.

5. Use according to claim 3 or 4, wherein the acylating agent substituted with a hydrocarbon group is polyisobutenyl succinic anhydride.

6. Use according to any one of claims 3 to 5, in which the compound comprising at least one tertiary amine group and at least one group chosen from primary amines, secondary amines and alcohols is chosen from amines of formula ( I) or (II) following:

(II) in which:

R6 and R7 are the same or different and represent, independently of each other, an alkyl group having 1 to 22 carbon atoms, preferably having 1 to 5 carbon atoms;

X is an alkylene group having 1 to 20 carbon atoms, preferably 1 to 5 carbon atoms; m is an integer between 1 and 5; n is an integer between 0 and 20; and

R8 is a hydrogen atom or a C1 to C22 alkyl group; and preferably said compound is chosen from the amines of formula (I).

7. Use according to any one of claims 3 to 6, wherein the quaternizing agent is selected from the group consisting of dialkyl sulfates, carboxylic acid esters; alkyl halides, benzyl halides, hydrocarbon carbonates, and hydrocarbon epoxides optionally mixed with an acid, alone or as a mixture, preferably from hydrocarbon epoxides or carboxylic acid esters, more preferably from carboxylic acid esters. styrene oxide and propylene oxide and more preferably the quaternizing agent is propylene oxide.

8. Use according to any one of the preceding claims, in which the additive (1) is chosen from polyisobutylene succinimides functionalized with a quaternary ammonium group.

9. Use according to any one of the preceding claims, in which the additive (2) consisting of a non-quaternary polyisobutylene succinimide results from the condensation:

- of a compound A consisting of a dicarboxylic acid substituted with a polyisobutylene group or of an anhydride of such a dicacid,;

- with a compound B consisting of a primary polyamine of general formula (VI) below:

H ₂ N - [- (CHRl - (CH ₂ ) _p -CHR2) _n -NH] _m -H (VI) in which R1 and R2, identical or different, represent hydrogen or a hydrocarbon group comprising from 1 to 4 carbon atoms, n is an integer varying from 1 to 3, m is an integer varying from 1 to 10, from preferably 1 to 4; and p is an integer equal to 0 or 1.

10. Use according to claim 9, wherein said additive (2) is obtained by condensation of compound A with compound B used in amounts such that the molar ratio A / B is in the range from 1: 1 to 1. : 3, preferably from 1: 1, 1 to 1: 2, even more preferably from 1: 1, 1 to 1: 1, 5.

11. Use according to any one of the preceding claims, in which the additive (3) consisting of a Mannich base is obtained by reaction of a phenol substituted with a hydrocarbon group, of an aldehyde and of an amine. , the hydrocarbon substituent of said phenol comprising from 6 to 400 carbon atoms, advantageously from 30 to 180 carbon atoms, preferably from 10 to 110, better still from 40 to 1 10 carbon atoms, and preferably being a polyisobutylene group.

12. Use according to any one of the preceding claims, in which the fuel contains a base obtained from one or more sources chosen from the group consisting of mineral, animal, plant and synthetic sources, and is preferably chosen from among hydrocarbon fuels, non-essentially hydrocarbon fuels and mixtures thereof.

13. Use according to any one of the preceding claims, in which the content of each additive (1) and (2) ranges from 5 to 10

000 ppm by weight, preferably from 5 to 1000 ppm by weight, more preferably from 10 to 500 ppm by weight, more preferably from 15 to 200 ppm by weight, and better still from 20 to 150 ppm by weight, relative to the weight total fuel composition.

14. Use according to one of the preceding claims, in which the content of the additive (3) ranges from 5 to 10,000 ppm by weight, preferably from 5 to 1000 ppm by weight, more preferably from 50 to 500 ppm by weight. weight, more preferably from 100 to 500 ppm by weight, and better still from 150 to 450 ppm by weight, relative to the total weight of the fuel composition.

15. Use according to one of the preceding claims, wherein the fuel further comprises one or more additional additives, other than the first, second and third additives, chosen from detergent additives, anti-corrosion agents, antioxidants, oils. carriers, dispersants, demulsifiers, tracers or markers, reodorants, friction modifiers, lubricity additives or lubricity additives, combustion aids (catalytic combustion and soot promoters), antiwear agents and conductivity modifiers.

16. Use according to any one of claims 1 to 15, for maintaining cleanliness (keep-clean effect) and / or clean (clean-up effect) the deposits in the internal parts of a spark-ignition engine chosen from among the following. following: the combustion chamber, and the fuel injection system, and preferably the fuel injection system.

17. Use according to any one of claims 1 to 15, for preventing and / or reducing deposits of coke and / or soap on the fuel inlet valves in an indirect injection spark ignition engine.

18. Use according to any one of claims 1 to 15, for preventing and / or reducing the sticking (or valve-sticking) of the fuel inlet valves in an indirect injection spark ignition engine.

19. Use according to any one of claims 1 to 15, in which the composition of additives is used in the fuel to reduce the fuel consumption of the engine (“Fuel Eco” action) and / or to minimize the loss of power of said engine. engine, and / or reduce pollutant emissions, in particular, particulate emissions from the combustion engine.

20. Use according to any one of claims 1 to 15, for reducing the fouling of the area of the pistons, rings and liners of the engine, preferably of a gasoline direct injection (or IDE) engine.

21. Use, to improve the detergency properties of a gasoline fuel, of a fuel concentrate comprising at least the additives (1), (2) and (3), as defined in any one of claims 1. to 11, 13 and 14, mixed with an organic liquid, said organic liquid being inert with respect to the first, second and third additives, and miscible with said fuel.

22. A method of maintaining the cleanliness and / or cleaning of at least one of the internal parts of a spark ignition engine (or internal combustion gasoline engine), comprising at least the following steps:

- the preparation of a fuel composition by additivation of a fuel with at least the additives (1), (2) and (3), as defined in any one of claims 1 to 11, 13 and 14 or with a concentrate as defined in claim 21, then

the combustion of said fuel composition in said spark ignition engine.