FR3143625A1 - Fuel composition comprising a renewable base, a fatty acid ester and a polysiloxane additive - Google Patents

Abstract

The subject of the present invention is a fuel composition comprising one or more bases consisting of fatty acids and/or hydrogenated fatty acid esters in association with at least one compound chosen from methyl and ethyl esters of fatty acids and at least one additive chosen from polysiloxanes and oxyalkylenated polysiloxanes. The present invention also relates to the use of such a fuel composition to power an engine, particularly of the Diesel type.

Description

Fuel composition comprising a renewable base, a fatty acid ester and a polysiloxane additive

The present invention relates to a fuel composition comprising one or more bases consisting of fatty acids and/or hydrogenated fatty acid esters such as hydrotreated vegetable oils in combination with at least one compound chosen from methyl and ethyl esters. of fatty acids and at least one additive chosen from polysiloxanes and oxyalkylenated polysiloxanes.

The present invention also relates to the use of such a composition to power an engine, particularly of the Diesel type.

STATE OF PRIOR ART

The fight against global warming requires developing new fuels with low environmental impact. A promising solution consists of replacing the bases of fossil origin traditionally used by bases of biological origin such as in particular bases resulting from hydrogenation processes of esters and natural fatty acids called in English Hydrogenated Esters and Fatty Acids (HEFA) for esters and hydrogenated fatty acids, such as for example bases resulting from hydrotreatment processes of vegetable oils, also known under the name HVO from the English "hydrotreated vegetable oil" that is to say hydrotreated vegetable oils. These bases are essentially made up of linear and branched paraffins (alkanes).

The trend is to increasingly increase the proportions of these renewable bases compared to conventional bases from petroleum distillation, or even to seek to formulate fuel compositions exclusively from such bases. In particular, for environmental reasons and/or availability of resources, the regulations of many countries encourage the introduction into fuels of increasing quantities of bases of renewable origin such as HEFA type bases and in particular HVOs bases.

Continuing its research into the development of fuel compositions of renewable origin, the Applicant sought to formulate compositions comprising such bases mixed with fatty acid esters such as methyl esters and ethyl esters of fatty acids.

However, the formulation of fuel compositions from such mixtures has proven to pose a number of difficulties, particularly in controlling foaming.

Due to their manufacturing processes but also due to the condensation of water during their transport and storage, fuel compositions can include a variable quantity of water of up to a few percent by mass. The presence of water generally results in the formation of emulsions within the fuel, which can be relatively stable and are the cause of many problems during the transportation, distribution and combustion of the fuel.

For example, the formation of emulsions complicates and slows down vehicle tank filling operations. Foam forms in fuel dispensing devices, which leads to overflow phenomena when filling the tanks. Furthermore, the large volume occupied by the foam in the vehicle tank leads to insufficient filling thereof. Additionally, emulsions can cause engine filters to clog and accelerate corrosion of engine parts.

The Applicant has found that the addition of fatty acid esters, including at moderate contents of a few percent by mass, to bases consisting of fatty acids and/or hydrogenated fatty acid esters, increased very significantly. important foaming phenomena.

Additionally, ionic detergent additives such as quaternary ammonium salts often used in fuel compositions tend to increase the stability of emulsions and slow fuel demulsification.

OBJECT OF THE INVENTION

The present invention aims to remedy the problems described above.

The present invention aims in particular to provide a fuel composition based on a mixture of fatty acids and/or hydrogenated fatty acid esters (HEFA) with methyl or ethyl esters of fatty acids, which has properties improved.

The Applicant has now discovered that the addition, to a fuel base consisting of fatty acids and/or hydrogenated fatty acid esters, of one or more methyl or ethyl esters of fatty acids in a minimum content of 2 % by mass in association with one or more additives chosen from polysiloxanes and oxyalkylenated polysiloxanes, made it possible to formulate a fuel composition in which the formation of emulsions is substantially reduced.

The subject of the present invention is therefore a fuel composition comprising:
a) at least 50% by mass, relative to the total mass of the composition, of one or more cuts of paraffinic hydrocarbons consisting of fatty acids and/or hydrogenated fatty acid esters ( HEFA);
b) at least 2% by mass, relative to the total mass of the composition, of one or more esters chosen from methyl esters and ethyl esters of fatty acids; And
c) one or more additives chosen from polysiloxanes and oxyalkylenated polysiloxanes.

In particular, the Applicant has unexpectedly discovered that the combination of the methyl and ethyl ester(s) of fatty acids and the additive(s) chosen from polysiloxanes and oxyalkylenated polysiloxanes made it possible to formulate fuel compositions based on acids. fatty and/or hydrogenated fatty acid esters such as, for example, hydrotreated vegetable oils having very low foaming levels. Not only is the volume of foam reduced, but also and surprisingly the time for the foam to disappear is greatly reduced.

The composition according to the invention has an extremely low level of foaming, even when it contains substantial contents of ionic detergent additives such as in particular quaternary ammonium salts and/or betaines.

The aromatic hydrocarbon content of the composition according to the invention is advantageously less than 5% by mass, preferably less than 2% by mass, more preferably less than 1% by mass, relative to the total mass of the composition.

According to a preferred embodiment, the naphthenic hydrocarbon content of the composition according to the invention is less than 5% by mass, preferably less than 4% by mass, relative to the total mass of the composition.

According to a particularly preferred embodiment, the total content of naphthenic hydrocarbons and aromatic hydrocarbons of the composition according to the invention is less than 5% by mass, preferably less than 4% by mass, relative to the total mass of the composition.

Its excellent properties make the fuel composition usable in many applications including modern motor vehicles, in particular vehicles comprising a Diesel engine, including the most advanced engines such as very high pressure direct injection Diesel engines.

Other objects, characteristics, aspects and advantages of the invention will appear even more clearly on reading the description and examples which follow.

In what follows, and unless otherwise indicated, the limits of a domain of values are included in this domain, in particular in the expressions “between” and “ranging from… to…”.
Furthermore, the expressions “at least one” and “at least” used in this description are respectively equivalent to the expressions “one or more” and “greater or equal”.
Finally, in a manner known per se, the term C _N compound or group denotes a compound or group containing N carbon atoms in its chemical structure.

DETAILED DESCRIPTION
Cutting paraffinic hydrocarbons (a)
The composition according to the invention comprises at least 50% by mass, relative to the total mass of the composition, of one or more cuts of paraffinic hydrocarbons consisting of fatty acids and/or fatty acid esters hydrogenated (HEFA).

Fatty acids and fatty acid esters can come from many sources, including vegetable oils and fats, animal oils and fats, recycled oils (e.g. edible oils, cooking oils).

According to a preferred embodiment, the paraffinic hydrocarbon cut(s) (a) consist of hydrotreated vegetable oils, also known under the name HVO (from the English “hydrotreated vegetable oils”). These are oils of plant origin which have undergone successive treatments including hydrotreatment and possible isomerization. The processes for preparing such hydrotreated vegetable oils are known per se.

Examples of plant raw materials suitable for obtaining such hydrotreated vegetable oils include rapeseed oil, canola oil, sunflower oil, soybean oil, hemp oil, olive oil, flaxseed oil, mustard oil, palm oil, castor oil, coconut oil.

Patent applications WO2016/185046 and WO2016/185047 describe non-limiting examples of methods making it possible to obtain cuts of hydrotreated vegetable oils usable as fuel bases.

The paraffinic hydrocarbon cut(s) (a) have a distillation range advantageously in the range going from 100 to 400°C, preferably from 130 to 350°C, and more preferably from 150 to 320°C.

The distillation range of said cut of paraffinic hydrocarbons is determined in accordance with standard NF EN ISO 3405.

The paraffinic hydrocarbon cut(s) (a) advantageously have a paraffin content greater than or equal to 90% by mass, preferably greater than or equal to 95% by mass, and better still greater than or equal to 96% by mass, for example relative to the total mass of the cut(s) (a).

By “paraffins” we mean in a manner known per se branched alkanes (also called iso-paraffins or iso-alkanes) and unbranched alkanes (also called n-paraffins or n-alkanes).

The paraffins present in the paraffinic hydrocarbon cut(s) according to the invention advantageously comprise from 10 to 20 carbon atoms. Preferably, they consist of at least 60% by mass, more preferably at least 80% by mass and better still at least 85% by mass of paraffins comprising from 12 to 18 carbon atoms, preferably from 14 to 18 carbon atoms, and even more preferably from 15 to 18 carbon atoms.

According to a preferred embodiment, the cut(s) of paraffinic hydrocarbons (a) used in the composition according to the invention contain at least 60% by mass, preferably at least 70% by mass of iso-paraffins, relative to to the total mass of the cut(s) (a). According to a particularly preferred embodiment, they contain at least 80% by weight of iso-paraffins, relative to the total mass of the cut(s) (a).

The paraffinic hydrocarbon cut(s) (a) have a content of aromatic compounds preferably less than or equal to 10,000 ppm by mass, more preferably less than or equal to 1500 ppm by mass, even more preferably less than or equal to 1000 ppm by mass .

Their content of naphthenic compounds is preferably less than or equal to 40,000 ppm by mass, more preferably less than or equal to 30,000 ppm by mass.

Their sulfur content is advantageously less than or equal to 10 ppm by mass, preferably less than or equal to 5 ppm by mass. Particularly preferably, the paraffinic hydrocarbon cut(s) (a) are completely free of sulfur.

The composition according to the invention preferably comprises at least 75% by mass, relative to the total mass of the composition, of one or more cuts of paraffinic hydrocarbons (a) as described above. Preferably, it contains at least 85% by mass of one or more cuts of paraffinic hydrocarbons (a), more preferably at least 90% by mass and better still at least 92% by mass, relative to the total mass. of the composition.

Methyl and ethyl esters of fatty acids (b)
The composition according to the invention comprises one or more methyl esters of fatty acids and/or one or more ethyl esters of fatty acids.

By fatty acid is meant a carboxylic acid comprising a saturated or unsaturated hydrocarbon chain having from 6 to 30 carbon atoms, preferably from 7 to 24 carbon atoms, and more preferably from 8 to 20 carbon atoms.

Said esters (b) are therefore chosen from esters of ethyl alcohol or methyl alcohol and one or more fatty acids as defined above.

These esters are known products per se. They can advantageously be obtained by reacting at least one oil chosen from vegetable oils, animal oils and used oils with methanol or ethanol, so as to obtain the corresponding esters by a chemical process called transesterification.

When the alcohol is methanol, we obtain a mixture of fatty acid methyl esters also called FAME.

When the alcohol is ethanol, we obtain a mixture of ethyl esters of fatty acids also called EEAG.

According to a preferred embodiment, the ester(s) (b) are chosen from fatty acid methyl esters. Preferably, the composition according to the invention comprises, as esters (b), a mixture of fatty acid methyl esters (FAME).

The composition according to the invention comprises the ester(s) b) in a minimum content of 2% by mass, relative to the total mass of the composition. Preferably, it comprises the ester(s) b) in a content ranging from 2 to 12% by mass, preferably from 4 to 10% by mass, and better still from 6 to 8% by mass, relative to the total mass. of the composition.

According to a preferred embodiment, the composition according to the invention comprises the ester(s) b) in a content of 7% by mass, relative to the total mass of the composition.

Preferably, the composition according to the invention comprises a mixture of fatty acid methyl esters (FAME) in a minimum content of 2% by mass, relative to the total mass of the composition. Preferably, it comprises a mixture of fatty acid methyl esters (FAME) in a content ranging from 2 to 12% by mass, preferably from 4 to 10% by mass, and better still from 6 to 8% by mass. , relative to the total mass of the composition.

According to a particularly preferred embodiment, the composition according to the invention comprises a mixture of fatty acid methyl esters (FAME) in a content of 7% by mass, relative to the total mass of the composition.

Polysiloxane additives (c)
The fuel composition comprises at least one additive chosen from polysiloxanes and oxyalkylenated polysiloxanes.

Preferably, the additive(s) (c) are chosen from polydialkylsiloxanes, and more preferably from polydimethylsiloxanes also called dimethicones.

According to a preferred embodiment, the additive(s) (c) are chosen from cyclic polydimethylsiloxanes containing from 4 to 8 silicon atoms.

Particularly preferably, the composition according to the invention contains decamethylcyclopentasiloxane.

The composition according to the invention comprises the additive(s) chosen from polysiloxanes and oxyalkylenated polysiloxanes (c) as described above in a preferential content ranging from 5 to 100 ppm, preferably from 8 to 50 ppm, and more preferably from 10 to 20 ppm by mass, relative to the total mass of the composition.

The composition according to the invention advantageously comprises decamethylcyclopentasiloxane at a preferential content ranging from 5 to 100 ppm, preferably from 8 to 50 ppm, and more preferably from 10 to 20 ppm by mass, relative to the total mass of the composition. .

Detergent additives (d)
According to a preferred embodiment, the fuel composition further comprises one or more detergent additives chosen from quaternary ammonium salts, amido alkyl betaines and mixtures thereof.

In a first variant, the fuel composition comprises one or more detergent additives chosen from quaternary ammonium salts, preferably chosen from:
(d1) quaternized polyisobutylene amines (PIBA);
(d2) quaternized polyether amines and
(d3) the quaternary ammonium salts obtained by reaction with a quaternization agent of a nitrogen compound comprising a tertiary amine function, this nitrogen compound being the product of the reaction of an acylating agent substituted by 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.

Quaternary ammonium salts (d3) are preferred. Thus, the fuel composition preferably comprises a detergent additive consisting of a quaternary ammonium salt, obtained by reaction with a quaternization agent of a nitrogen compound comprising a tertiary amine function, this nitrogen compound being the product of the reaction of an acylating agent substituted by 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.

Said nitrogen compound is the product of the reaction of an acylating agent substituted by a hydrocarbon group and a compound comprising both an oxygen atom or a nitrogen atom capable of condensing with said nitrogen atom. acylation 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.

The acylating agent is substituted by a hydrocarbon group. The term "hydrocarbon" group means any group having a carbon atom directly attached to the rest of the molecule (ie to the acylating agent) and mainly having an aliphatic hydrocarbon character.

Hydrocarbon groups according to the invention may also contain non-hydrocarbon groups. For example, they can contain up to one non-hydrocarbon group for every ten carbon atoms provided that the non-hydrocarbon group does not significantly modify the mainly hydrocarbon character of the group. We can cite as an example of such groups well known to those skilled in the art, hydroxyl groups, halogens (in particular chloro- and fluoro- groups), alkoxy, alkylmercapto and alkyl sulfoxy groups.

We will nevertheless prefer hydrocarbon substituents not containing such non-hydrocarbon groups and having a purely aliphatic hydrocarbon character.

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 approximately 200 carbon atoms.

The hydrocarbon substituent of the acylating agent preferably has a number average molecular mass (Mn) of between 170 to 2800, for example between 250 to 1500, more preferably between 500 to 1500 and, even more preferably between 500 to 1100. A range of values of M _n between 700 and 1300 is particularly preferred, for example from 700 to 1000.

As an 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 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 homo-or inter-polymers.

Alternatively, the hydrocarbon substituent of the acylating agent may be obtained from other sources, for example from high molecular weight alkene monomers (e.g., 1-tetracontene) and their chlorinated analogues or hydrochlorinated, aliphatic petroleum fractions, e.g. paraffin waxes, their cracked, chlorinated and/or hydrochlorinated analogues, white oils, synthetic alkenes, e.g. produced by Ziegler-Natta process (e.g. polyethylene greases ) 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 essentially saturated, that is, it contains no more than one unsaturated carbon-carbon bond for every ten carbon-carbon single bonds. present.

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

According to a preferred embodiment, the hydrocarbon substituent of the acylating agent is a polyisobutene (PIB) group. We particularly prefer the so-called highly reactive polyisobutenes (PIB). By highly reactive polyisobutenes (PIB) is meant 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, the preferred PIBs are those having more than 80 mol% and up to 100 mol% of vinylidene terminal groups as described in document EP1344785.

According to a particularly preferred embodiment, the acylating agent substituted by a hydrocarbyl group is a polyisobutenyl-succinic anhydride (PIBSA).

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 substitute for the acylating agent. By internal olefin is meant any olefin containing mainly a 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 weight of alpha-olefin, advantageously less than 5% by weight or less than 2% by weight.

The 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: N,N - dimethylaminopropylamine, N,N-diethylaminopropylamine, N,N-dimethylaminoethylamine. Said compound may also be chosen from heterocyclic compounds substituted with alkylamines such as 1-(3-aminopropyl)-imidazole and 4-(3-aminopropyl)morpholine, 1-(2-aminoethyl)piperidine, 3,3 - diamino-N-methyldipropylamine, 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 may also be chosen 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, N,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-diisopropanolamine, N'-(3-(Dimethylamino)propyl)- N,N-dimethyl-1,3-propanediamine; 2-(2-dimethylaminoethoxy)ethanol and N,N,N’-trimethylaminoethylethanolamine.

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):
(I)
(II)

in which :
R6 and R7 are identical or different and represent, independently of each other, an alkyl group having 1 to 22 carbon atoms;
X is an alkylene group having 1 to 20 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.

When the nitrogen compound comprises an amine of formula (I), R8 is advantageously a hydrogen atom or a C1 to C16 alkyl group _, preferably a C1 to C10 alkyl group _, even more preferably a C1 to C6 alkyl group . R8 may, for example, be chosen from the group consisting of hydrogen, methyl, ethyl, propyl, butyl and their isomers. Preferably R8 is a hydrogen atom.

When the nitrogen 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 nitrogen compound is the product of the reaction of the acylating agent substituted by a hydrocarbon group and a diamine of formula (I).

In this embodiment:
- R6 and R7 can represent, independently of each other, a C1 to C16 alkyl group_,preferably a C1 to C10 alkyl group ;
_-R6 and R7 may 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 each other, a C1 to C4 group, preferably a methyl group;
- carbon. X particularly preferably represents an ethylene, propylene or butylene group, in particular a propylene group.

According to a particularly preferred embodiment, the nitrogen compound is the reaction product of a succinic acid derivative substituted by a hydrocarbon group, preferably a polyisobutenyl-succinic anhydride, and of an alcohol or 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 by 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 -CO ₂ H (open form). Thus, in certain embodiments the nitrogen 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 also also comprises a carboxyl group -CO ₂ H unreacted (open form).

The quaternary ammonium salt forming the second additive according to the present invention is directly obtained by reaction between the nitrogen 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 sulfates, carboxylic acid esters; alkyl halides, benzyl halides, hydrocarbon carbonates, and hydrocarbon epoxides optionally mixed with an acid, alone or in mixture.

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

Thus, if a quaternization 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 quaternization agent may include halides such as chloride, iodide or bromide; hydroxides; sulfonates; bisulfites; alkyl sulfates such as dimethyl sulfate; sulfones; phosphates; C1-C12 alkylphosphates _; C1-C12 dialkylphosphates; borates; C1-C12 alkylborates; nitrites; nitrates; carbonates; of the
bicarbonates; alkanoates; C1-C12 O,O-dialkyldithiophosphates _, alone or in a mixture.

According to a particular embodiment, the quaternization agent can be chosen from derivatives of dialkyl sulfates such as dimethyl sulfate, of N-oxides, of sulfones such as propane- and butane-sulfone, 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 groups (alkyls) of hydrocarbon carbonates can contain from 1 to 50, from 1 to 20, from 1 to 10 or 1 to 5 carbon atoms per group. According to one embodiment, the hydrocarbon carbonates contain two hydrocarbon groups which may be identical or different. As an example of hydrocarbon carbonates, we can cite dimethyl or diethyl carbonate.

According to a preferred embodiment, the quaternization agent is chosen from hydrocarbon epoxides represented by the following formula (III):
(III)
in which R9, R10, R11 and R12 may be identical or different and independently represent a hydrogen atom or a C ₁ to C ₅₀ hydrocarbon group. As a non-limiting 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.

Such hydrocarbon epoxides can be used as a quaternization agent in combination with an acid, for example with acetic acid. Hydrocarbon epoxides can also be used alone as a quaternization agent, especially without additional acid. Without being bound by this hypothesis, it would seem that the presence of the carboxylic acid function in the molecule favors 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 and alcohols (including polyhydric alcohols) can be used alone or in a mixture. Preferred protic solvents have a dielectric constant greater than 9.

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

According to another embodiment, the quaternization agent is chosen from the compounds of formula (IV):
(IV)
in which R13 is an optionally substituted alkyl, alkenyl, aryl and aralkyl group, and R14 is a C ₁ to C ₂₂ 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 chosen, for example from carboxylic acid esters having a pKa of 3.5 or less. The compound of formula (IV) is preferably chosen from esters of substituted aromatic carboxylic acid, alpha-hydroxycarboxylic acid and 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 by one or more groups chosen from carboalkoxy, nitro, cyano, hydroxy, SR ₁₅ and NR ₁₅ R ₁₆ radicals. Each of the groups R ₁₅ and R ₁₆ may be a hydrogen atom or an optionally substituted alkyl, alkenyl, aryl or carboalkoxy group. Each of the groups R ₁₅ and R ₁₆ advantageously represents the hydrogen atom or an optionally substituted C1 to C22 alkyl group, preferably the hydrogen atom or a C1 to C16 alkyl group _, more preferably the hydrogen atom or a C1 to C10 alkyl group _, even more preferably the hydrogen atom or a C1 to C4 alkyl group. R ₁₅ is preferably a hydrogen atom and R ₁₆ a hydrogen atom or a C1 to C4 group. Advantageously, R ₁₅ and R ₁₆ are both a hydrogen atom.

According to one embodiment, R13 is an aryl group substituted by one or more groups chosen from hydroxyl, carboalkoxy, nitro, cyano and NH ₂ radicals. R13 may 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 radicals OH, NH ₂ , NO ₂ or COOMe, preferably OH or NH ₂ . R13 is preferably a hydroxyaryl group, in particular 2-hydroxyphenyl.

According to a particular embodiment, R14 is an alkyl or alkylaryl group. R14 may be a C1 to C16 alkyl group_,preferably in C1 to C10, advantageously in C1 to C8. R14 can be a C1 to C16 alkylaryl group, preferably C1 to_C10,advantageously in C1 to C8. R14 can for example be chosen from methyl, ethyl, propyl, butyl, pentyl, benzyl groups 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 following formula (V):
(V)
in which R17 and R18 are identical or different and are independently chosen 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; methyl-, ethyl-, propyl-, butyl-, pentyl-, hexyl-, benzyl-, phenyl- or allyl esters of 2-hydroxy-2-ethylbutyric acid; 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. The preferred esters are C1 to C4 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 includes more than one acid group, we will refer to the first dissociation constant.

The compound of formula (IV) may 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-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 whose polyisobutylene group (PIB) has a number average molecular mass (Mn) of between 700 and 1000 and dimethyl-aminopropylamine.

In a second variant, the fuel composition comprises one or more detergent additives chosen from amido alkyl betaines. These are preferably chosen from those of formula (VI) below:
(VI)
in which
R₁is a C hydrocarbon chain₁to C₃₄, linear or branched,
R₂is a hydrogen atom or a C hydrocarbon chain₁to C₁₅,
R₃is a C hydrocarbon chain₁to C_15,And
R₄and R₅are identical or different and chosen independently of each other from a hydrogen atom and a C hydrocarbon chain₁to C_10,preferably in C₁to C_6,it being understood that the R groups₄and R₅may contain one or more nitrogen groups and/or may be linked together to form one or more rings.

Preferably, in formula (VI), R ₁ is a C ₈ to C ₃₀ hydrocarbon chain, linear or branched, preferably C ₁₂ to C ₂₄ , more preferably C ₁₆ to C ₂₀ .

Preferably, in formula (VI), R ₂ is a hydrogen atom or a C ₁ to C _{8 hydrocarbon chain,} preferably a hydrogen atom. Preferably, in formula (I), R ₃ is a C ₁ to C ₈ hydrocarbon chain, preferably C ₂ to C ₄ .

Preferably, in formula (VI), R ₄ and R ₅ are identical or different and chosen independently of each other from a hydrogen atom and a C ₁ to C _{6 hydrocarbon chain,} it being understood that the R ₄ and R ₅ groups may contain one or more nitrogen groups and/or may be linked together to form a ring; more preferably R ₄ and R ₅ are identical and represent a methyl group or an ethyl group and even more preferably a methyl group.

In a preferred embodiment, amido alkyl betaine is obtained by reacting:
(i) a tertiary amine of formula R ₄ R ₅ R' ₃ N:
- where R _4, R ₅ are as defined above for formula (VI), the preferred meanings of these groups for formula (VI) also being preferred for said tertiary amine;
- where R' ₃ designates a group of formula -R ₃ -N(R ₂ )-CO-R ₁ , where R ₁ , R ₂ and R ₃ are as defined above for formula (VI), the meanings preferred of these groups for formula (VI) being also preferred for said tertiary amine; with
(ii) acetic acid substituted by at least one halogen, or one of its salts, or one of its ester or amide derivatives.

Preferably, compound (ii) is acetic acid substituted with halogen, or a salt of such an acid.

The salts may include alkali or alkaline earth metals, or ammoniums, including but not limited to sodium, lithium, calcium, potassium, magnesium, triethyl ammonium or triethanol ammonium salts.

In a preferred embodiment, chloroacetic acid or sodium or potassium chloroacetate salts are used.

The molar ratio of the quantity of carboxylic acid/ester/amide or one of their salts (ii) to the quantity of tertiary amine (i) is advantageously included in the range going from 1:0.1 to 0.1:1.0.

In a particularly preferred embodiment, amido alkyl betaine is the reaction product:
(i) a tertiary amine substituted with a hydrocarbon group chosen from (C ₈ -C ₃₀ alkyl) amidopropyldi(C ₁ -C ₄ alkyl)amines and (C ₈ -C ₃₀ alkenyl) amidopropyldi(alkyl C ₁ -C ₄ )amines; preferably from (C ₈ -C ₃₀ alkyl) amidopropyldimethylamines and (C ₈ -C ₃₀ alkenyl) amidopropyldimethylamines; with
(ii) acetic acid substituted with a halogen, or one of its salts, or one of its ester or amide derivatives;
said reaction product preferably being free of non-covalent anionic species.

Preferably, compound (i) is oleylamido propyl dimethylamine and compound (ii) is sodium chloroacetate.

The composition according to the invention may comprise the detergent additive(s) as described above in a preferential content ranging from 5 to 1000 ppm, preferably from 10 to 500 ppm, and more preferably from 50 to 200 ppm by weight, for example relative to the total weight of the composition.

Demulsifying additives (e)
According to a preferred embodiment, the fuel composition further comprises at least one demulsifying additive chosen from polyoxyalkylenated condensation resins of at least one alkyl-phenol with at least one aldehyde.

The demulsifying additive(s) are preferably chosen from polyoxyalkylenated copolymers of:
- at least one alkyl-phenol consisting of a phenol nucleus substituted by one or more alkyl groups having from 1 to 30 carbon atoms, preferably a monoalkyl-phenol whose alkyl group comprises from 6 to 14 carbon atoms, and
- at least one aldehyde having 1 to 4 carbon atoms.

The alkyl phenol(s) are preferably chosen from para-alkyl phenols. Nonylphenol is preferably used.

The aldehyde(s) are preferably chosen from formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, 2-ethylhexanal, benzaldehyde and mixtures thereof. Formaldehyde is preferably used.

The demulsifying additive(s) are more preferably chosen from polyoxyalkylenated copolymers of para-nonylphenol with formaldehyde, and more preferably from polyoxyethylenated and polyoxypropylenated copolymers of para-nonylphenol with formaldehyde (in particular the compound having CAS number 63428-92-2 .

The composition according to the invention may comprise the demulsifying additive(s) (e) as described above in a preferential content ranging from 5 to 100 ppm, preferably from 8 to 50 ppm, and more preferably from 10 to 20 ppm in mass, relative to the total mass of the composition.

The composition according to the invention advantageously comprises one or more polyoxyalkylenated copolymers of para-nonylphenol with formaldehyde at a preferential content ranging from 5 to 100 ppm, preferably from 8 to 50 ppm, and more preferably from 10 to 20 ppm by mass , relative to the total mass of the composition.

Other additives:
The composition according to the invention may also comprise one or more additional additives, different from methyl and ethyl esters of fatty acids (b) and polysiloxane additives (c) as described above.

The composition may further comprise one or more antioxidant agents which may in particular be chosen from phenolic antioxidants and amine antioxidants.

The phenolic antioxidants may in particular be chosen from alkyl phenols.

Preferably, the alkyl-phenol additive(s) are chosen from compounds comprising one or two phenolic core(s) substituted by one or more C ₁ to C ₄ alkyl groups, and more preferably from compounds comprising a phenolic ring substituted with one or more C ₁ to C ₄ alkyl groups. The C ₁ to C ₄ alkyl group(s) are more preferably chosen from methyl, ethyl and t-butyl (or tert-butyl) groups.

The alkyl-phenol additive(s) are more preferably chosen from methyl-t-butyl phenols, dimethyl-t-butyl phenols, ethyl-t-butyl phenols, t-butyl phenols, di-t-butyl phenols, tri-t-butyl phenols, di-t-butyl-methyl phenols, di-t-butyl-di-methyl phenols, trimethyl phenols and mixtures thereof.

Preferred compounds are chosen from 2,6-di-t-butyl-4-methylphenol (BHT), 4,6-di-tert-butyl-2-methylphenol, t-butyl hydroquinone (TBHQ), 2 .6 and 2,4 di-t-butyl phenol, 2,4-dimethyl-6-t-butyl phenol, 2,5-dimethyl-4-t-butyl phenol, 2,4,6-tri -t-butyl phenol, 2,3,6-trimethyl phenol, 2,4,6- trimethyl phenol, 4,4'- methylene bis (2,6-di-t-butyl phenol) (CAS No. 1 18-82-1), and their mixtures.

Particularly preferably, the composition according to the invention contains 2,6-di-t-butyl-4-methyl phenol (BHT).

The amine antioxidants may in particular be chosen from aliphatic, cycloaliphatic and aromatic amines. Dicyclohexylamine is particularly preferred.

The antioxidant agent(s) may be present in a content ranging from 1 to 500 ppm, preferably from 5 to 200 ppm, and more preferably from 10 to 100 ppm by mass, relative to the total mass of the composition.

The composition may further comprise one or more metal passivating agents, chosen from triazole derivatives, alone or in mixture.

The term “triazole derivatives” means all compounds comprising a triazole unit, that is to say a 5-membered aromatic cyclic unit, comprising two double bonds and 3 nitrogen atoms. Depending on the position of the nitrogen atoms, we distinguish between 1,2,3-triazole units (called V-triazoles) and 1,2,4-triazole units (called S-triazoles). As an example of triazole units, mention may be made of benzotriazole or tolyltriazole.

The metal passivating agent(s) are preferably chosen from amines substituted with triazole groups, alone or in mixture. The term “triazole group” means any substituent containing a triazole unit as defined above.

The metal passivating agent(s) are more preferably chosen from N,N-bis(2-ethylhexyl)-[(1,2,4-triazol-1-yl)methyl]amine (CAS 91273-04-0) and N,N'-bis-(2 ethylhexyl)-4-methyl-1H-benzotriazole amine (CAS 80584-90-3), alone or in a mixture.

We can also cite and the passivating agents described on page 5 of application US2006/0272597.

The metal passivating agent(s) may be present in a content ranging from 0.2 to 50 ppm, preferably from 0.5 to 25 ppm, and more preferably from 1 to 15 ppm by mass, relative to the total mass of the composition.

The composition may further comprise one or more chelating agents (or metal sequestering agents), which may in particular be chosen from amines substituted by Ν,Ν'-disalicylidene groups, such as Ν,Ν'-disalicylidene 1,2 -diaminopropane (DMD).

The chelating agent(s) may be present in a content ranging from 0.1 to 100 ppm, preferably from 0.2 to 50 ppm, and more preferably from 0.5 to 20 ppm by weight, even more preferably from 0.5 at 10 ppm by mass, relative to the total mass of the composition.

The composition according to the invention may also comprise one or more other additives commonly used in fuels, different from the additives described above.

The composition may, typically, comprise one or more other additives chosen from anti-corrosion agents, dispersants, tracers, biocides, reodorants, friction modifiers, lubricating additives or lubricity additives, anti-corrosion agents. -wear and/or agents modifying conductivity.

Uses:
The present invention also relates to the use of a fuel composition as described above to power an engine of a vehicle or a stationary machine.

Preferably, the composition according to the invention is used to power a compression ignition engine or Diesel engine, and more preferably a Diesel engine of a vehicle. The composition according to the invention can be used in particular in the following different vehicles: light vehicles, heavy goods vehicles (trucks of different loads called “medium duty” and “heavy duty”, household waste skips, buses, coaches, etc.) and non-road vehicles (construction and/or works vehicles, agricultural vehicles such as tractors, railway vehicles such as trains, boats such as ships, barges, etc.).

According to a preferred embodiment, the composition according to the invention is used to power a compression ignition engine (or Diesel engine) of a vehicle chosen from motor vehicles and non-motor vehicles, preferably a hybrid Diesel engine or a direct injection Diesel engine, more preferably a direct injection Diesel engine and in particular a Diesel engine with a Common-Rail injection system (CRDI in English “Common Rail Direct Injection”).

In this embodiment, the engine is preferably present in a non-motor vehicle, including road vehicles such as for example trucks, garbage trucks, buses, and non-road vehicles such as for example construction vehicles. and/or works, agricultural vehicles, boats.

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

EXAMPLES
The examples below were produced from a cut of paraffinic hydrocarbons (hereinafter cut A) consisting of a hydrotreated vegetable oil (HVO) whose characteristics are detailed in Table I below:

Characteristic Method Value Density at 15°C ISO 12185 779.9 kg/m ³ Viscosity at 40°C ISO 3104 2.9mm ² /s Cloud point (PTR)° ASTM D7346 -36°C Filterability limit temperature (TLF) EN 116 -39°C Distillation profile ISO 3405 Initial point 216.0°C Point 5% vol. 252.4°C Point 10% vol. 262.1°C Item 20% vol. 269.8°C Point 30% vol. 273.4°C Point 40% vol. 275.7°C Point 50% vol. 277.8°C Point 60% vol. 279.7°C Item 70% vol. 282.1°C Item 80% vol. 285.0°C Point 90% vol. 289.2°C Item 95% vol. 293.0°C Period 304.3°C Distilled volume 98.6ml Residue 1.3ml Losses 0.1ml Aromatic compound content EN12916 0% by mass

This cut of hydrocarbons consists of 99.9% by mass of paraffins, including 92.6% of iso-paraffins (hereinafter i-paraffins) and 7.3% by mass of n-paraffins.

Its exact composition is detailed in Table II below:

Number of C atoms n-paraffins i-paraffins naphthenes i-naphthenes 7 2.35 0.39 8 0.09 0.20 0.01 9 0.16 0.43 0.01 10 0.17 0.80 0.01 11 0.14 0.84 12 0.13 0.99 13 0.15 1.02 14 0.86 1.54 0.01 0.01 15 9.55 0.01 0.05 16 2.43 31.15 0.01 17 14.22 18 0.80 30.71 0.02 19 0.23 0.01 20 0.01 0.31 21 0.03 22 0.06 23 0.02 24 0.01 27 0.08 Total 7.29 92.56 0.03 0.12

Fuel compositions C0, C1 and C2 were prepared, by adding to cut A the following ingredients:
- Cyclomethicone = decamethylcyclopentasiloxane; And
- FAME: mixture of methyl esters of rapeseed oil fatty acids, the characteristics of which appear in Table III below (the fatty acid contents being expressed as a percentage by mass relative to the total mass of fatty acids ):

[Table III C16:0 C18:0 C18:1 C18:2 C18:3 Iodine index Rapeseed methyl ester
5
2.5
59
21
9
111

The contents of the ingredients of each composition are detailed in Table IV below:

Compositions C0 C1 C2 HVO content (Cut A)
(% by mass) 100 93 93 FAME content
(% by mass) - 7 7 Cyclomethicone content
(ppm by mass) - - 15

Compositions C0 and C1 are comparative and composition C2 conforms to the invention.

Foaming tests:
The foaming level of each of the compositions was determined using the method described in standard NF M 07-075.

The test consists of injecting a defined quantity (100 mL) of composition at a constant pressure of 400 millibars into a 250 mL glass measuring cylinder.

The foaming of each composition is thus determined, in terms of volume of foam formed and time for the foam to disappear.

The results obtained are detailed in Table V below:

Composition C0 C1 C2 Foam volume (mL) 50 80 40 Foam disappearance time (s) 2 18 1.8

These results show that the addition of fatty acid methyl esters to cut A consisting of HVO generates a significant increase in foaming, in terms of foam volume and especially stability of the foam formed (the time for the disappearance of the foam is multiplied by 9).

The addition of the polysiloxane type additive in a very low content (15 ppm by mass) makes it possible to very effectively reduce the foaming of the mixture, to a level which is surprisingly lower than that of cut A.

Claims (15)

Fuel composition comprising:
a) at least 50% by mass, relative to the total mass of the composition, of one or more cuts of paraffinic hydrocarbons consisting of fatty acids and/or hydrogenated fatty acid esters ( HEFA);
b) at least 2% by mass, relative to the total mass of the composition, of one or more esters chosen from methyl esters and ethyl esters of fatty acids; And
c) one or more additives chosen from polysiloxanes and oxyalkylenated polysiloxanes. Composition according to the preceding claim, characterized in that the paraffinic hydrocarbon cut(s) (a) consist of hydrotreated vegetable oils (HVO). Composition according to any one of the preceding claims, characterized in that the paraffinic hydrocarbon cut(s) (a) have a paraffin content greater than or equal to 90% by mass, preferably greater than or equal to 95% by mass, and better still greater than or equal to 96% by mass, relative to the total mass of the cut(s) (a). Composition according to any one of the preceding claims, characterized in that the paraffinic hydrocarbon cut(s) (a) consist of at least 60% by mass, preferably at least 80% by mass, more preferably at least 85% by mass of paraffins comprising from 12 to 18 carbon atoms, preferably from 14 to 18 carbon atoms, and even more preferably from 15 to 18 carbon atoms. Composition according to any one of the preceding claims, characterized in that the ester(s) (b) are chosen from methyl esters of fatty acids. Composition according to the preceding claim, characterized in that it comprises, as esters (b), a mixture of fatty acid methyl esters (FAME). Composition according to any one of the preceding claims, characterized in that it comprises the ester(s) (b) in a content ranging from 2 to 12% by mass, preferably from 4 to 10% by mass, more preferably from 6 at 8% by mass, and better still 7% by mass, relative to the total mass of the composition. Composition according to any one of the preceding claims, characterized in that the additive(s) (c) are chosen from polydialkylsiloxanes, preferably from polydimethylsiloxanes, more preferably from cyclic polydimethylsiloxanes containing from 4 to 8 silicon atoms, and better still still the composition contains decamethylcyclopentasiloxane. Composition according to any one of the preceding claims, characterized in that it comprises the additive(s) chosen from polysiloxanes and oxyalkylenated polysiloxanes (c) in a content ranging from 5 to 100 ppm, preferably from 8 to 50 ppm, and more preferably from 10 to 20 ppm by mass, relative to the total mass of the composition. Composition according to any one of the preceding claims, characterized in that it further comprises one or more detergent additives chosen from quaternary ammonium salts, amido alkyl betaines and mixtures thereof. Composition according to the preceding claim, characterized in that it comprises one or more detergent additives chosen from quaternary ammonium salts, preferably chosen from:
(d1) quaternized polyisobutylene amines (PIBA);
(d2) quaternized polyether amines; And
(d3) the quaternary ammonium salts obtained by reaction with a quaternization agent of a nitrogen compound comprising a tertiary amine function, this nitrogen compound being the product of the reaction of an acylating agent substituted by a hydrocarbon group and a compound comprising at least one tertiary amine group and at least one group chosen from primary amines, secondary amines and alcohols;
and preferably among quaternary ammonium salts (d3). Composition according to any one of claims 10 and 11, characterized in that it comprises one or more detergent additives chosen from amido alkyl betaines, preferably chosen from those of formula (VI) following:
(VI)
in which
R₁is a C hydrocarbon chain₁to C₃₄, linear or branched,
R₂is a hydrogen atom or a C hydrocarbon chain₁to C₁₅,
R₃is a C hydrocarbon chain₁to C_15,And
R₄and R₅are identical or different and chosen independently of each other from a hydrogen atom and a C hydrocarbon chain₁to C_10,preferably in C₁to C_6,it being understood that the R groups₄and R₅may contain one or more nitrogen groups and/or may be linked together to form one or more rings Composition according to any one of the preceding claims, characterized in that it further comprises at least one demulsifying additive chosen from resins for condensing at least one alkyl-phenol with at least one aldehyde, polyoxyalkylenated, and preferably from polyoxyalkylenated copolymers of:
- at least one alkyl-phenol consisting of a phenol nucleus substituted by one or more alkyl groups having from 1 to 30 carbon atoms, preferably a monoalkyl-phenol whose alkyl group comprises from 6 to 14 carbon atoms, and
- at least one aldehyde having 1 to 4 carbon atoms. Use of the composition as defined in any one of the preceding claims to power an engine of a vehicle or a stationary machine, preferably a Diesel engine, and more preferably a Diesel engine of a vehicle chosen from vehicles automobiles and non-motor vehicles including road vehicles such as trucks, garbage trucks, buses; and non-road vehicles such as construction and/or works vehicles, agricultural vehicles, boats. Use according to the preceding claim, to power a Diesel engine of a vehicle, preferably a hybrid Diesel engine or a direct injection Diesel engine, more preferably a direct injection Diesel engine.