EP0530094B1 - Motor fuel additive formulation comprising ester products and a detergent-dispersant agent - Google Patents

Abstract

Additive formulation for engine fuels comprising at least one constituent (A) and at least one constituent (B), the said constituent (A) consisting of at least one composition containing the products resulting from the reaction of at least one dicarboxylic compound (D) in which the carboxylic functional groups are separated by not more than 6 carbon atoms, with at least one glycol or polyoxyalkylene glycol monoether (E) of general formula (I): R<1>-O-(R<2>-O)n-H in which R<1> denotes a hydrocarbon group containing from 1 to 30 carbon atoms, R<2> denotes a divalent hydrocarbon group containing from 2 to 6 carbon atoms and n is a number from 1 to 60; and the said constituent (B) consisting of at least one detergent-dispersant product. This formulation preferably additionally includes a constituent (C) chosen from the group made up of mineral or synthetic lubricating oils and polyglycols which are soluble in the fuel. Use as multifunctional additives for fuels employed in internal combustion engines, in particular for those employed in spark ignition engines.

Description

The present invention relates to additive formulations, in particular for fuels, comprising products with an ester function and a detergent-dispersant. These formulations can be used as multifunctional additives for fuels and in particular for fuels used in spark ignition engines.

The use of conventional fuels very often leads to the fouling of the various parts of the engine as a result of the incomplete vaporization and combustion of the fuel in the intake system and in the combustion chambers and also quite often as a result of the presence of traces of lubricants.

In particular, in the case of positive-ignition engines, the formation and accumulation of deposits in the combustion chambers disturb the normal operating conditions of the engine.

These deposits significantly modify the heat exchanges between the combustion chambers and the engine cooling system by forming an insulating layer.

This results in an increase in the temperature in the chambers to which the admitted gas mixture is subjected. The auto-ignition of these gases is then favored, which causes the well-known phenomenon of engine rattling to appear.

Furthermore, the accumulation of these deposits in the combustion chambers can lead to a reduction in the volume of the combustion zone, which then results in an increase in the compression ratio of the engine. This phenomenon also promotes the appearance of rattling. Furthermore, the deposits which form in the various parts of the engine in contact with the fuel can partially absorb a part of this fuel, thus contributing to a modification of the oxidizer-fuel mixture with a fuel depletion phase during absorption and an enrichment phase in the event of a desorption of this fuel. The modification of the richness of the fuel-air mixture no longer allows the engine to work in optimal conditions.

In order to remedy the fouling, it is possible to carry out periodic, particularly expensive, cleaning of the organs concerned, in particular of the valves.

The accumulation of deposits in the engines and in particular on the intake valves can also be reduced by the use of fuels containing certain additives, for example detergent-type additives possibly combined for example with anticorrosion or anti-deposit additives for rooms combustion.

Additives, well known in the trade, for example those of the polyisobuteneamine type, are usually associated with a mineral or synthetic oil and are capable of causing increased fouling of the combustion chambers and therefore an increase in the octane requirement of the engine with greater sensitivity to the rattling phenomenon.

Among the numerous additives described in the prior art, mention may be made of the condensation products of polyalkenylsuccinic anhydrides on polyamines, such as, for example, tetraethylenepentamine, which are in particular described in US-A-3172892. These additives give good results in terms of anti-corrosion properties, but are not effective as valve detergents.

Mention may also be made of the condensation products of polyalkenylsuccinic anhydrides on hydroxyimidazolines, and in particular on 1- (2-hydroxyethyl) imidazolines substituted in position 2 by an alkyl or alkenyl group, such as those described in the patent application EP-A-74724. The products described in this application are good additives for engine fuels and have a significant anti-corrosion action but are not very effective in terms of the detergency of the carburetor.

Contamination of the combustion chambers occurs gradually during engine operation. The latter is characterized by its octane requirement which corresponds to the minimum octane level of fuel necessary for the engine in order to operate without rattling. When the value of the engine octane requirement exceeds, in particular as a result of fouling of the combustion chambers, the value of the octane number of the fuel used to supply this engine, the rattling phenomenon is observed. The increase in engine octane requirements conventionally constitutes, for those skilled in the art, the ORI phenomenon according to the Anglo-Saxon abbreviation of "Octane Requirement Increase".

In order to limit the appearance of rattling and its harmful consequences on the engine such as increased fatigue and wear of the vital parts, it is possible to remedy an excessive octane requirement of the engine by using, subject to availability and at a cost. economical, a fuel with an octane number higher than that previously used. It is also possible to periodically clean the combustion chambers in order to eliminate the deposits formed and reduce the octane requirement of the engine. This operation is however long and very expensive.

Numerous patent documents describe additives which can be used in particular in motor fuels. Belgian patent BE 811678 describes fuel compositions containing a lubricant in the form of an ester and in particular of an ester of diacids and of alcohol or diols. Among the diols mentioned are polyoxyalkylene glycols. The preferred diacids which can be used according to this application include adipic acid, azelaic acid and sebacic acid. US-A-3429817 describes lubricating compositions containing synthetic esters resulting from the reaction of 2 moles of a glycol having 2 to 5 carbon atoms and a diacid whose carboxylic groups are separated from one other by at least 9 carbon atoms. US-A-3836470 describes lubricant compositions and fuel compositions containing a dispersing additive resulting in particular from the reaction of a succinic acid, comprising a hydrocarbon side chain and having at least 30 carbon atoms in its molecule, on at least one polyoxyalkylene glycol or one polyoxyalkylene glycol ether. Mention may also be made of the compositions such as those described for example in patent application EP-A-327097 which have good anti-ORI properties and good detergent properties at the intake valve level, but detergent properties at the level of the relatively limited single point injector. Furthermore, these compositions are not described as having good anticorrosion properties.

We have now surprisingly discovered formulations, as described below, which can be used in particular as multifunctional additives for engine fuels, in particular for fuels used in spark-ignition engines. The formulations of the present invention have excellent detergent properties at the intake valves and the carburetor, and have very good anticorrosion properties.

These formulations, used as multifunctional additives in engine fuels, and more particularly in fuels used for spark-ignition engines, largely inhibit, or reduce, the formation of deposits on the intake valves, as well as the fouling of carburetors. or injectors; moreover, they greatly reduce the corrosion of the various mechanical parts with which the fuel comes into contact.

• 1/ les mélanges de polyisobutènes et de polyisobutènes-amines;
• 2/ les produits, tels que décirts dans la demande EP-A-349369, résultant de la réaction, dans une première étape, d'au moins un dérivé succinique choisi dans le groupe formé par les anhydrides alcénylsucciniques et les anhydrides polyalcénylsucciniques de masse moléculaire moyenne en nombre de 200 à 3000 sur au moins une 1-(2-hydroxyéthyl)imidazoline substituée en position 2 par un radical alkyle ou alcényle, linéaire ou ramifié, ayant de 1 à 25 atomes de carbone, le rapport molaire imidazoline/dérivé succinique étant de 0,1:1 à 0,9:1, de préférence de 0,2 :1 à 0,8 :1 et le plus souvent de 0,3 : 1 à 0,7 : 1, ladite étape étant effectuée dans des conditions telles que l'on forme et que l'on élimine au moins 0,15 mole d'eau par mole d'imidazoline engagée ; et, dans une deuxième étape, de la réaction du produit issu de la première étape sur au moins une polyamine répondant à l'une des formules générales suivantes :
  
  
  dans lesquelles R³ représente un atome d'hydrogène ou un groupe hydrocarboné ayant de 1 à 60 atomes de carbone, Z est choisi parmi les groupes -O-, et -NR⁵- dans lesquels R⁵ représente un atome d'hydrogène ou groupe hydrocarboné ayant de 1 à 60 atomes de carbone, R³ et R⁵ pouvant former ensemble avec l'atome d'azote auquel ils sont liés un hétérocycle, chacun des R⁴ indépendamment représente un atome d'hydrogène ou un groupe hydrocarboné ayant de 1 à 4 atomes de carbone, p est un nombre entier de 2 à 6, m est un nombre entier de 1 à 10 lorsque Z est -NR⁵ - et un nombre entier de 2 à 10 lorsque Z est -O-, D, E, F et G, identiques ou différents, représentent chacun un groupe hydrocarboné divalent ayant de 2 à 6 atomes de carbone, a est un nombre entier de 1 à 60, b et c, identiques ou différents, sont chacun zéro ou un nombre entier de 1 à 50 et la somme a + b + c est un nombre entier de 1 à 60, la quantité de polyamine mise en réaction étant d'au moins 0,1 mole par mole de dérivé succinique introduit dans la première étape.; la quantité totale d'imidazoline substituée et de polyamine étant de préférence de 0,8 à 1,2 mole par mole de dérivé succinique; et
• 3/ les produits, tels que décrits par la demanderesse dans le brevet US-A-4375974, résultant d'au moins une polyamine, ayant au moins un groupe amino primaire et répondant à la formule générale (III) ci-avant, sur au moins un dérivé succinique tels que ceux décrits ci-avant;

ladite formulation contenant en outre au moins un constituant (C) choisi dans le groupe formé par les huiles lubrifiantes minérales ou synthétiques et les polyglycols, solubles dans ledit carburant, de masse moléculaire moyenne en nombre de 480 à 2 100 et de formule générale (V):

        (V)    HO-R-(-O-R-)_x-O-R-OH

dans laquelle chacun des groupes R indépendamment représente un groupe hydrocarboné ayant de 2 à 6 atomes de carbone et x représente le degré moyen de polymérisation, ces polyglycols étant par exemple tels que ceux décrits par la demanderesse dans la demande de brevet européen EP-A-349369.The subject of the present invention is an additive formulation, usable in particular as a multifunctional fuel additive, which comprises at least one constituent (A) and at least one constituent (B), said constituent (A) consisting of at least one composition comprising the products resulting from the reaction of maleic anhydride with at least one glycol or polyoxyalkylene glycol monoether (E) having a molecular mass of 500 to 2,500 and corresponding to the general formula (I):

(I) R ¹ -O- (R ² -O) _n -H

in which R ¹ represents an alkyl, aryl, arylalkyl or alkylaryl group of 1 to 30 carbon atoms, preferably from 1 to 25 carbon atoms, R ² represents an alkylene group, having 2 to 5 carbon atoms, of formula general (II):

(II) CH ₂ -CR ³ H

wherein R ³ represents a hydrogen atom, a methyl group, an ethyl group or a propyl group; and n is a number from 1 to 60; said reaction being carried out at a temperature of about 100 ° C to about 210 ° C with a molar ratio of compound (E) to maleic anhydride of about 1.5: 1 to about 5: 1 and for a sufficient time so that the products obtained have a corrected acid number, as defined below, of approximately 3000 to 30,000; and said component (B) consisting of at least one detergent-dispersant product chosen from the group formed by

• 1 / mixtures of polyisobutenes and polyisobutenes-amines;
• 2 / the products, as described in application EP-A-349 369, resulting from the reaction, in a first step, of at least one succinic derivative chosen from the group formed by alkenyl succinic anhydrides and polyalkenyl succinic anhydrides of molecular mass number average from 200 to 3000 on at least one 1- (2-hydroxyethyl) imidazoline substituted in position 2 by an alkyl or alkenyl radical, linear or branched, having from 1 to 25 carbon atoms, the imidazoline / succinic derivative molar ratio being from 0.1: 1 to 0.9: 1, preferably from 0.2: 1 to 0.8: 1 and the more often from 0.3: 1 to 0.7: 1, said step being carried out under conditions such that one forms and eliminates at least 0.15 mole of water per mole of imidazoline used; and, in a second step, of the reaction of the product resulting from the first step on at least one polyamine corresponding to one of the following general formulas:
  
  
  in which R ³ represents a hydrogen atom or a hydrocarbon group having from 1 to 60 carbon atoms, Z is chosen from the groups -O-, and -NR ⁵ - in which R ⁵ represents a hydrogen atom or group hydrocarbon having from 1 to 60 carbon atoms, R ³ and R ^{5 being} able to form together with the nitrogen atom to which they are linked a heterocycle, each of R ⁴ independently represents a hydrogen atom or a hydrocarbon group having from 1 with 4 carbon atoms, p is an integer from 2 to 6, m is an integer from 1 to 10 when Z is -NR ⁵ - and an integer from 2 to 10 when Z is -O-, D, E , F and G, identical or different, each represent a divalent hydrocarbon group having from 2 to 6 carbon atoms, a is an integer from 1 to 60, b and c, identical or different, are each zero or an integer of 1 to 50 and the sum a + b + c is an integer from 1 to 60, the quantity of polyamine reacted being at least m less than 0.1 mole per mole of succinic derivative introduced in the first stage .; the total amount of substituted imidazoline and polyamine being preferably from 0.8 to 1.2 moles per mole of succinic derivative; and
• 3 / the products, as described by the applicant in US-A-4375974, resulting from at least one polyamine, having at least one primary amino group and corresponding to the general formula (III) above, on to at least one succinic derivative such as those described above;

said formulation also containing at least one constituent (C) chosen from the group formed by mineral or synthetic lubricating oils and polyglycols, soluble in said fuel, of number average molecular weight from 480 to 2,100 and of general formula (V ):

(V) HO-R - (- OR-) _x -OR-OH

in which each of the groups R independently represents a hydrocarbon group having from 2 to 6 carbon atoms and x represents the average degree of polymerization, these polyglycols being for example such as those described by the applicant in European patent application EP-A- 349369.

The corrected acid number mentioned to characterize the constituent (A) is an index calculated from the acid number evaluated according to AFNOR standard T-60-112 and the average molecular weight of the polyoxyalkylene glycol monoether considered as follows: corrected acid number (IAc) = acid number x Molecular weight monoether of polyoxyalkylene glycol.

The formulations according to the present invention can be used in particular as additives in the fuels used in spark-ignition engines in which they make it possible in particular to limit the increase in octane requirement (ORI) of these engines and therefore to limit, to delay or even to avoid, the appearance of the rattling phenomenon. These formulations also have an anti-corrosion action which can be observed both with the fuels used in spark ignition engines and in those used in auto ignition engines (Diesel engine).

As examples of fuels which may contain at least one formulation of additives according to the present invention, mention may be made of gasolines as well as those which are defined by standard ASTM D-439, diesel or diesel fuel such as those which are defined by ASTM D-975. These fuels can also contain other additives, such as for example, in particular in the case of fuels used for spark-ignition engines, anti-knock additives such as lead compounds (for example tetraethyl lead), ethers such as methyltertiobutylether or methyltertioamylether or a mixture of methanol and tert-butyl alcohol and anti-icing additives. It is also possible to add the formulations of the present invention to a non-hydrocarbon fuel such as for example an alcohol or a mixture of alcohols.

Preferably, the constituent (A) of the formulations of the invention may result from the reaction of maleic anhydride with at least one compound (E) under conventional conditions well known to those skilled in the art of product formation comprising ester functions. The preferred component (A) according to the present invention is obtained by carrying out the reaction at a temperature usually from about 120 ° C to about 200 ° C, and for a time sufficient for the products obtained to have an acid number preferred answer from about 4000 to about 25000.

Among the compounds (E), it is preferred to use those in which R ¹ represents a linear or branched alkyl group, in which n is a number from 5 to 50.

As specific examples of polyxyalkylene glycols, mention may be made of alkyl monoethers of glycol or of polyxyalkylene glycols such as alkyl monoethers of polypropylene glycol, alkyl monoethers of polyethylene glycol and alkyl monoethers of polypropylene glycol and ethylene glycol. The alkyl group of these products most often contains at least 3 carbon atoms and is most often linear. As an example of an alkyl group, mention may be made of n-pentyl and n-heptyl groups. These oxyalkylated products are commercial products sold by the company SHELL under the generic name OXYLUBE or by the company ICI. These compounds usually have a molecular mass of approximately 500 to approximately 2500 and most often of approximately 600 to approximately 2000. By way of examples of these compounds, mention may be made of those sold by the company ICI having a block structure of the type R ⁵ -O- + q (propylene oxide) + p (ethylene oxide) in which R ⁵ represents an alkyl group having from 1 to 20 carbon atoms, q is the number of oxide units and p is the number of ethylene oxide units.

According to the invention, the mixtures (B1) of polyisobutenes and polyisobutene-amines can comprise a majority proportion of polyisobutene-ethylene diamine and a minority proportion of polyisobutene. These mixtures are most often used dissolved in a hydrocarbon solvent so as to facilitate their incorporation into the fuel. The proportion of amino polymer within these blends is usually from about 50% to 80% by weight and for example from about 60% by weight and the proportion of hydrocarbon polymer is usually from about 5% to about 30% by weight. weight and preferably from about 10% to about 25% by weight.

dans laquelle z est un nombre d'environ 10 à environ 40, de préférence d'environ 30 à environ 35 et par exemple d'environ 33.Polyisobutene ethylene diamine is a compound of general formula:

in which z is a number from approximately 10 to approximately 40, preferably from approximately 30 to approximately 35 and for example approximately 33.

dans laquelle t est un nombre d'environ 10 à environ 40, de préférence d'environ 30 à environ 35 et par exemple d'environ 33.Polyisobutene is a compound of general formula:

in which t is a number from approximately 10 to approximately 40, preferably from approximately 30 to approximately 35 and for example approximately 33.

The solvent used to dissolve the polymeric compounds and facilitate their incorporation into the fuel is most often a light aromatic distillate. Can be used as component (B) comprising, dissolved in a light aromatic distillate, a polyisobutene and a polyisobutene-ethylene diamine as described above, the product sold by the company CHEVRON CHEMICAL COMPANY under the trade name ORONITE OGA -472. ORONITE OGA-472 is a composition comprising approximately 60% by weight of polyisobutene-ethylene diamine, approximately 27% by weight of polyisobutene and approximately 13% by weight of light aromatic distillate comprising xylene and C ₉ alkylbenzenes.

In the preparation of the constituents (B2) of the formulations of the present invention, the succinic acid or anhydride used usually has a number average molecular weight of about 200 to 3000, preferably 500 to 2000 and most often 700 to 1500. These succinic derivatives are widely described in the prior art; they are for example obtained by the action of at least one alpha olefin or of a chlorinated hydrocarbon on maleic acid or anhydride. The alpha olefin or the chlorinated hydrocarbon used in this synthesis can be linear or branched, and usually contain from 10 to 150 carbon atoms, preferably from 15 to 80 carbon atoms and most often from 20 to 75 carbon atoms in their molecule. This olefin can also be an oligomer, for example a dimer, a trimer or a tetramer, or a polymer of a lower olefin, for example having 2 to 10 carbon atoms, such as ethylene, propylene, n-butene-I, isobutene , n-hexene-I, n-octene-I, methyl-2-heptene-1 or methyl-2-propyl-5-hexene-1. It is possible to use mixtures of olefins or mixtures of chlorinated hydrocarbons.

As examples of succinic anhydrides used to prepare component (B), there may be mentioned n-octadecenylsuccinic anhydride, dodecenylsuccinic anhydride and polyisobutenyl succinic anhydrides, often called PIBSA, having a number-average molecular mass such as defined above.

1- (2-hydroxyethyl-imidazolines substituted in position 2 by an alkyl or alkenyl radical having from 1 to 25 carbon atoms are usually commercial compounds or which can be synthesized for example by reaction of at least one organic acid with the N- (2-hydroxyethyl) -ethylenediamine The reaction proceeds by a first step of amidification followed by cyclization The organic acids used usually have from 2 to 26 carbon atoms, they are preferably aliphatic monocarboxylic acids.

Examples include acetic acid, propanoic acid, butanoic acid, caproic acid, capric acid, lauric acid, myristic acid, palmitic acid, l stearic acid, behenic acid, cerotic acid and the following unsaturated fatty acids: CH ₃ -CH ₂ -CH = CH - (- CH ₂ -) ₇ -COOH dodecylenic acid CH ₃ - (- CH ₂ -) ₅ -CH = CH - (- CH ₂ -) ₇ -COOH palmitoleic acid CH ₃ - (- CH ₂ -) ₇ -CH = CH - (- CH ₂ -) ₇ -COOH oleic acid CH ₃ - (- CH ₂ -) ₅ -CHOH-CH ₂ -CH = CH - (- CH ₂ -) ₇ -COOH ricinoleic acid CH ₃ - (- CH ₂ -) ₁₀ -CH = CH - (- CH ₂ -) ₄ -COOH petroselenic acid CH ₃ - (- CH ₂ -) ₅ -CH = CH - (- CH ₂ -) ₉ -COOH vaccenic acid CH ₃ - (- CH ₂ -) ₄ -CH = CH-CH ₂ -CH = CH - (- CH ₂ -) ₇ -COOH linoleic acid CH ₃ - (- CH ₂ -) ₉ -CH = CH - (- CH ₂ -) ₇ -COOH gadoleic acid CH ₃ - (- CH ₂ -) ₉ -CH = CH - (- CH ₂ -) ₉ -COOH ketoleic acid CH ₃ - (- CH ₂ -) ₇ -CH = CH - (- CH2-) ₁₁ -COOH erucic acid CH ₃ - (- CH ₂ -) ₇ -CH = CH - (- CH ₂ -) ₁₃ -COOH selacholeic acid

For example, use 1- (2-hydroxyethyl) -2-heptadecenyl imidazoline, prepared for example from oleic acid and N- (2-hydroxyethyl) -ethylenediamine. This preparation is for example described in patent US-A-2987515. Mention may also be made, by way of example, of 1- (2-hydroxyethyl) -2-methyl imidazoline, prepared for example from acetic acid and N- (2-hydroxyethyl-) ethylenediamine. 1- (2-hydroxyethyl) -2 heptadecenylimidazoline is marketed by the company CIBA-GEIGY under the name "Amine-O" and by the company PROTEX under the name "lmidazoline-O".

The first stage of preparation of component (B2) according to the invention is usually carried out by progressive addition of the imidazoline derivative to a solution of the succinic derivative in an organic solvent, at ordinary temperature, then heating to a temperature usually between 65 ° C and 250 ° C and preferably between 80 ° C and 200 ° C. The organic solvent used in this preparation has a boiling point between 65 ° C and 250 ° C and is usually chosen so as to be able to allow the elimination of the water formed during the condensation of imidazoline on the derivative succinic, preferably in the form of a water-organic solvent azeotrope. An organic solvent will usually be used such as for example benzene, toluene, xylenes, ethylbenzene or a hydrocarbon cut such as for example the commercial cut SOLVESSO 150 (190-209 ° C) containing 99% by weight of aromatic compounds. It is possible to use mixtures of solvents, for example a mixture of xylenes. The duration of heating after the end of the addition of imidazoline is usually 0.5 to 7 hours, preferably 1 to 5 hours. This first step will preferably be continued at the chosen temperature until the end of the evolution of the water formed during the reaction.

The amount of water removed during this first step is usually about 0.15 to 0.6 moles and most often about 0.5 moles per mole of imidazoline involved in the reaction. At least one polyamine, preferably diluted in an organic solvent, is gradually added to the product or mixture resulting from this first step, after optional cooling, and then usually heated to a temperature between 65 ° C. and 250 ° C. and preferably between 80 ° C and 200 ° C. The solvent used in the second step is preferably the same as that in the first step and the temperature is also the same during these two steps. The reactions are usually carried out at a temperature corresponding to the reflux temperature. The duration of this heating during this second step is usually 0.1 to 7 hours and preferably 0.2 to 5 hours. The amount of polyamine used is at least 0.1 mole per mole of succinic anhydride introduced during the first step and it is preferably such that the total amount of imidazoline substituted and of polyamine used in the preparation is 0.8 to 1.2 moles, preferably 0.9 to 1.1 moles per mole of succinic derivative. The substituted imidazoline to polyamine molar ratio is preferably from 1: 1 to 7: 1 and most preferably from 1: 1 to 3: 1.

The amount of water removed during this second step is usually such that the amount of total water removed during the two successive reactions represents from 0.2 to 0.7 mole per mole of succinic derivative.

The polyamines of formula (III) are preferably those in which R ³ is a hydrogen atom or a hydrocarbon group having from 1 to 30 carbon atoms, Z is preferably a group -NR ⁵ - in which R ⁵ represents preferably a hydrogen atom or a hydrocarbon group having from 1 to 30 carbon atoms, each of R ⁴ independently represents preferably a hydrogen atom or a methyl group, p is an integer from 2 to 4 and when Z is a group -NR ⁵ - m is preferably an integer from 1 to 5.

Among the compounds of formulas (III) above, advantageously those in which Z is -NR ⁵ -, R ³ , R ⁴ and R ⁵ each represent a hydrogen atom, p is equal to 2 and m is a number integer from 1 to 5 or those in which R ³ represents a hydrocarbon group preferably having from 5 to 24 carbon atoms, Z represents a group -NR ⁵ - in which R ⁵ is a hydrogen atom, R ⁴ represents an atom of hydrogen, p is an integer from 2 to 4, preferably 3, and m is an integer from 1 to 5, preferably 1.

The hydrocarbon groups R ³ and R ⁵ are usually alkyl, alkenyl, linear or branched, aryl, aryl-alkyl (aralkyl), alkyl-aryl (alkaryl) or cycloaliphatic groups. The groups R ³ and R ⁵ are preferably alkyl groups or alkenyls, linear or branched. The hydrocarbon group R ⁴ is usually a preferably linear alkyl group, for example methyl, ethyl, n-propyl or n-butyl.

As specific compounds, mention may be made of: ethylenediamine, propylenediamine, triethylenetetramine, tripropylenetetramine, tetraethylenepentamine, trimethylenediamine, hexamethylene diamine, 2,2,4 and 2,4,4 hexamethylene diamine, di (trimethylene) triamine, N-1,3-alkyl diamino-propane, for example N-dodecyldiamino-1,3 propane, N-tetradecyldiamino-1,3 propane, N-hexadecyldiamino-1,3 propane, N -octadécyldiamino-1,3 propane, N-éicosyldiamino-1,3 propane and N-docosyldiamino-1,3 propane; mention may also be made of N-alkyldipropylene triamines, for example N-hexadecyldipropylene triamine, N-octadecyldipropylene triamine, N-eicosyldipropylene triamine and N-docosyldipropylene triamine; mention may also be made of N-alkenyldiamino-1,3 propane and N-alkenyldipropylene triamines, for example N-octadecenyldiamino-1,3 propane, N-hexadecenyldiamino-1,3 propane, N-dodecylenyldiamino-1,3 propane , N-octadecadienyldiamino-1,3 propane and N-docosényldiamino-1,3 propane. As examples of disubstituted diamines N, N, there may be mentioned N, N-diethyl-1,2-diamino ethane, N, N-diisopropyl-1,2-diamino ethane, N, N-dibutyl diamino-1, 2 ethane, N, N-1,4-diethyl diamino-butane, N, N-dimethyl-1,3-diamino propane, N, N-diethyl-1,3-diamino propane, N, N-dioctyl diamino- 1,3 propane, N, N-didécyl diamino-1,3 propane, N, N-didodécyl diamino-1,3 propane, N, N-ditétradécyl diamino-1,3 propane, N, N-dihexadécyl 1,3-diamino propane, N, N-dioctadecyl 1,3-diamino propane, N, N-didodecyldipropylene triamine, N, N-ditetradecyldipropylene triamine, N, N-dihexadecyldipropylene triamine, N, N-dioctadecyldipropylene triamine, N-methyl, N-butyl diamino-1,2 ethane, N-methyl N-octyl diamino-1,2 ethane, N-ethyl, N-octyl diamino-1,2 ethane, N-methyl , N-decyl diamino-1,2 ethane, N-methyl N-dodecyl diamino 1,3 propane, N-methyl, N-hexadecyl diamino-1,3 propane and N-ethyl N-octadecyl diamino-1, 3 prop donkey.

Examples of etheramines that may be mentioned are N- (3-octyloxy-propyl) 1,3-diamino propane, N- (3-decyloxy-propyl) 1,3-diamino propane, N- [(trimethyl- 2,4,6 decyl) 3-oxy propyl] diamino-1,3 propane.

It should be understood that it is possible to bring into play as polyamine compound one or more compounds corresponding to formula (III) and / or (IV). As specific examples of a mixture of compounds corresponding to formula (III), mention may be made of:
cuts of fatty diamines corresponding to the formula R ³ -NH - (- CH ₂ -) ₃ -NH _{2 in} which the R ³ groups are C ₈ , C ₁₀ , C ₁₂ , C ₁₄ , C ₁₆ aliphatic hydrocarbon radicals, C ₁₈ , C ₂₀ and C ₂₂ , in approximate molar proportions given in Table I below.

The polyamines of formulas (IV) are preferably those in which R ³ and R ⁵ each represent a hydrogen atom, D, E, F and G, identical or different, each represent an alkylene group having from 2 to 4 atoms carbon for example ethylene, trimethylene, methylethylene, tetramethylene, methyltrimethylene, 1-methyltrimethylene and 2-methyltrimethylene, a is an integer from 1 to 60 and b and c are equal to zero or a is an integer from 1 to 59 , c is zero or an integer such that the sum a + c is from 1 to 59 and b is an integer from 1 to 50, with in each case the sum a + b + c equal to an integer from 1 to 60.

dans lesquelles a est 2, 3, 5, 6 ou environ 33

dans laquelle b est environ égal à 8, 9, 15, 16 ou 40 et a + c est environ 2 ou 3.As specific compounds of formula (IV), mention may be made of those corresponding to the formulas:

(IV ₁ ) NH ₂ -CH ₂ -CH ₂ - (- O-CH ₂ -CH ₂ -) _a -NH ₂

where a is 2, 3, 5, 6 or about 33

where b is approximately equal to 8, 9, 15, 16 or 40 and a + c is approximately 2 or 3.

These products are in particular marketed by the company TEXACO Chemical under the name Jeffamine EDR 148 for the product of formula (IV1) in which a = 2, Jeffamine D-230 for a product of formula (IV2) of average molecular mass in number of 230, Jeffamine D-400 for a product of formula (IV2) of number average molecular mass of 400, Jeffamine D-2000 for a product of formula (IV2) of number average molecular mass of 2000, Jeffamine ED-600 for a product of formula (IV3) of number average molecular mass of 600, Jeffamine ED-900 for a product of formula (IV3) of number average molecular mass of 900 and Jeffamine ED-2001 for a product of formula (IV3) of mass number average molecular of 2000.

With regard to the preparation of the products (B3) used as detergent-dispersants in the formulations of the invention, the reaction carried out under conditions of formation and elimination of the reaction water is most often carried out at a temperature of approximately 120 ° C. to approximately 200 ° C. with an amine to succinic derivative molar ratio of approximately 0.9: 1 to approximately 1.2: 1. This reaction can be carried out in the absence of solvent or in the presence of a solvent such as for example an aromatic hydrocarbon or a cut of hydrocarbons having a boiling point of approximately 70 ° C to approximately 250 ° C.

Furthermore, in an advantageous embodiment of the formulations of the invention, the constituent (C) is a polyglycol, having a polydispersity index of approximately 1 to approximately 1.25 and preferably from about 1 to 1.15, of general formula (V) in which each of the groups R independently represents an alkylene group, linear or branched, having from 2 to 4 carbon atoms, preferably a group ethylene or propylene.

Among the particularly preferred polyglycols of general formula (V), mention may be made of those in which each of the groups R represents a propylene group of formula:

CH ₃ -CH-CH ₂ -

The polyglycol used is preferably a polyglycol of average molecular mass in numbers from 600 to 1800 and most often from 650 to 1250.

Among the mineral or synthetic lubricating oils which can be used as constituent (C), there may be mentioned by way of nonlimiting example for mineral oils the oil 600 NS, the main characteristics of which will be given below, and for the synthetic lubricating oils ethers and polyol esters and in particular polyoxyalkylene glycol ethers.

The formulations according to the invention are in particular usable as an additive having good anti-corrosion activity for a fuel based on hydrocarbons or on a mixture of hydrocarbons and at least one oxygenated compound chosen from the group formed by alcohols and ethers. These formulations can also be used as a multifunctional additive having in particular good anti-ORI and detergent-dispersant properties for an engine fuel, for a spark-ignition engine, based on hydrocarbons or a mixture of hydrocarbons and at least minus an oxygenated compound chosen from the group formed by alcohols and ethers. Usually these formulations are added to the fuel so as to obtain a mass concentration, of the additive composition in the engine fuel, of 10 to 10,000 ppm and most often of 100 to 2000 ppm.

In the formulations according to the present invention the weight ratio of component (A) to component (B) [(A) / (B)] is usually from about 0.05: 1 to about 2: 1 and preferably from about 0.1: 1 to about 1: 1. When the formulation also includes a constituent (C) the weight ratio of constituent (B) to constituent (C) [(B) / (C)] is usually from about 0.1: 1 to about 5: 1 and preferably from about 0.2: 1 to about 2: 1.

EXAMPLE 1

715 g (0.5 mole) of polypropylene glycol mono-alkyl ether of number-average molecular weight is charged into a 2-liter reactor equipped with mechanical stirring, a condenser and a temperature control system Mn from 1430, sold by the company ICI under the trade name VG 95. The reactor is brought to 186 ° C. with stirring, for 30 minutes (min), in order to dehydrate the medium. 54 g (0.55 mole) of maleic anhydride are then added slowly, then the medium is maintained at 186 ° C. for 18 hours. The reactor temperature is reduced to 50 ° C, then 715 g of VG 95 reagent are added slowly as well as 0.65 g of concentrated sulfuric acid. The mixture is brought to 180 ° C for 10 hours. The final composition obtained is clear.

The infrared spectrum shows two absorption bands (1740 cm ^-1 and 1650 cm ^-1 ) characteristic of the ester function on the one hand and of the residual unsaturation of the final product. Analysis by gel permeation chromatography (refractive index detection, polyethylene glycol (PEG) calibration) shows that the product has a weight-average molecular weight of approximately 4,000. The acid number evaluated according to AFNOR T 60112 standard and corrected for molecular weight (IAc) is 18,000.

EXAMPLE 2

629 g (0.44 mole) of polyoxyalkylene glycol VG 95 monoether and 0.57 g of concentrated sulfuric acid are charged into a 2 liter reactor equipped with mechanical stirring, a condenser and a temperature control system. . The reactor is brought to 185 ° C. with stirring for 30 minutes and then 23.7 g (0.24 mole) of maleic anhydride are added slowly. The mixture is maintained at 185 ° C for 28 hours. A composition is obtained whose acid number evaluated according to AFNOR standard T 60112 and corrected for molecular weight (IAc) is 15,300.

EXAMPLE 3 (Detergent composition)

1018 g of polyisobutenyl succinic anhydride (PIBSA), resulting from the condensation of polyisobutene (polyisobutene of average molecular mass number 920), on maleic anhydride (the assay of the anhydride functions of this product shows that one has 0, 7 anhydride function per theoretical mole of PIBSA) and 1018 g of xylene are loaded into a 2-liter reactor equipped with mechanical stirring, a Dean-Stark separator and a temperature regulation system.

Then proceeded, at room temperature and with stirring, to the dropwise addition of 148 g (0.423 mole) of 1- (2-hydroxy-ethyl) -2-heptadecenyl imidazoline diluted in 148 g of xylene. The addition is carried out in 30 minutes and accompanied by a rapid increase in temperature of the reaction mixture of approximately 5 ° C. The mixture is then brought to reflux for 3 hours with elimination of reaction water by azeotropic distillation. The amount of water collected is 2.3 ml (milliliter) The progress of the reaction can also be followed by infrared spectrometry at the absorption band of the imine function at 1660 cm ^-1 which disappears gradually during the reaction.

The reactor temperature is lowered to 50 ° C. and then maintained at this value during the time of the gradual addition (dropwise) of 56 g (0.297 mole) of tetraethylenepentamine diluted in 49 g of xylene. At the end of this addition the mixture is again brought to reflux for 15 minutes. Water elimination again occurs. The total amount of water collected during these two reaction stages is 7.2 ml. The infrared spectrum shows two absorption bands (1710 cm ^-1 and 1770 cm ^-1 ) characteristic of the succinimide function with a shoulder ( 1740 cm ^-1 ) characteristic of the ester function.

This gives a solution, at 50% by weight of active material, in xylene, of a composition whose elemental analysis reveals a nitrogen content of 2.55% by weight.

EXAMPLE 4

Solutions are prepared, in xylene, of formulations F1 to F5 comprising various weight quantities of the constituents (A), (B) and (C) defined below.
Component (A) is formed by one of the compositions obtained in Examples 1 and 2.

The constituent (B) is formed by the composition obtained in Example 3 or by a composition of the polymeric type and, preferably, that of the polyisobutene-ethylene-diamine and polyisobutene type such as one of those described in the documents. EP-A-327097, US-A-4141693, US-A-4028065 and US-A-3966429. In this case, constituent (B) will be designated below by the initials PBA; this constituent is then the composition sold by the company CHEVRON CHEMICAL under the name ORONITE OGA -472 comprising approximately 60 parts by weight of polyisobutene-ethylene diamine, 13 parts by weight of polyisobutene and 27 parts by weight of a light aromatic distillate comprising xylene and alkylbenzenes having 9 carbon atoms in their molecule.

dont la masse moléculaire moyenne en nombre est de 922 (x = 13,6) et dont la polydispersité est de 1,1, soit encore, une huile lubrifiante minérale ou synthétique. De préférence, on considère l'huile minérale de base 600 NS bien connue de l'homme du métier et caractérisée par les spécifications intersyndicales françaises suivantes :

• viscosité cinématique à 40 °C comprise entre 109 et 124 centiStokes (cSt)
• indice de viscosité minimum de 95
• point d'écoulement maximum de - 9 °C
• indice d'acide maximum de 0,05.

Component (C) is either a polypropylene glycol of formula:

whose number average molecular mass is 922 (x = 13.6) and whose polydispersity is 1.1, or again, a mineral or synthetic lubricating oil. Preferably, the base mineral oil 600 NS is well known to those skilled in the art and characterized by the following French inter-union specifications:

• kinematic viscosity at 40 ° C between 109 and 124 centiStokes (cSt)
• minimum viscosity index of 95
• maximum pour point of - 9 ° C
• maximum acid number of 0.05.

The formulation F1 according to the present invention contains the constituent (A) formed by the composition obtained in Example 1, the constituent (B) formed by the composition obtained in Example 3 and the constituent (C) formed by the polypropylene glycol described above. These constituents are used in a weight ratio, in terms of active material, A: B: C of 1: 5: 5.

The formulation F2 (comparison formulation) contains the constituent (B) formed by the composition obtained in Example 3 as well as the constituent (C) formed by the polypropylene glycol described above, but no constituent (A). The active matter B: C weight ratio is 1: 1.

The formulation F3 (comparison formulation) contains the constituent (B) designated by the initials PBA as well as the constituent (C) formed by the mineral oil 600 NS in a weight ratio of active material B: C of 1: 3.

The formulation F4 according to the present invention contains the constituent (A) formed by the composition obtained in Example 1, the constituent (B) designated by the initials PBA and the constituent (C) formed by the mineral oil 600 NS, in a weight ratio of active ingredient A: B: C of 1: 2: 6.

The formulation F5 according to the present invention contains the constituent (A) formed by the composition obtained in Example 2, the constituent (B) formed by the composition obtained in Example 3 and the constituent (C) formed by the polypropylene glycol, in a weight ratio of active ingredient A: B: C of 1: 5: 5.

EXAMPLE 5

• 552 secondes (s) de ralenti sous une charge nulle
• 5 s de régime transitoire
• 2762 s à 3500 tr/min (tours par minute) sous une charge de 58 Newton-mètre (N.m)
• 276 s à 3500 tr/min sous une charge de 86 N.m
• 5 s de régime transitoire.

A series of tests is carried out in order to evaluate the control properties of the increase in octane requirement of the various additive formulations described in Example 4 in a lead-free fuel. The tests were carried out on test bench Renault F 3 N having a displacement of 1721 ^cm3 and a compression ratio of 9.5. This engine is equipped with a multi-point injection system, which allows a measure of the octane requirement of each cylinder. The test procedure is a cyclic procedure; each cycle comprising 5 successive operating periods:

• 552 seconds idling under zero load
• 5 s transient
• 2762 s at 3500 rpm (revolutions per minute) under a load of 58 Newton meters (Nm)
• 276 s at 3500 rpm under a load of 86 Nm
• 5 s transient regime.

The duration of each test is 200 hours. At the start of each test, the engine is conditioned with new valves and the combustion chambers are free of any deposits. The octane requirements of each cylinder are then determined at the start of the test as follows: the richness of the air-fuel mixture admitted is adjusted to the manufacturer's reference value for the measurement regime considered (2,000 rpm) / min and 3,500 rpm). The octane requirement of each cylinder is successively determined by supplying them with reference fuels made up of mixtures of isooctane and n-heptane. The value of the octane requirement of a cylinder corresponds to the octane number of the reference fuel which shows the knock phenomenon. The cyclic procedure described above is then applied by supplying the engine with test fuel containing or not containing additive. At the end of the test, a new measurement of the octane requirements of each cylinder is carried out as above. The average of the differences calculated between the octane requirement at the end of the test and the octane requirement at the start of the test for each cylinder constitutes, for the measurement regime considered, the value of the increase in octane requirement (ORI).

The results below are expressed in the form of average ORI at the end of the test at the two measurement regimes considered and the effectiveness of the additives is evaluated in terms of difference between the average ORI at the end of the test without additive (fuel alone) and the average ORI at the end of the test with additive. This difference is called ORD and is all the greater as the additive tested limits the increase in octane requirement of the engine.

• 29 % aromatiques
• 13 % d'oléfines
• 58 % de composés saturés (paraffines + naphténiques).

The fuel used in these assessments is an unleaded premium fuel, an engine octane rating of 87 and a research octane rating of 99. This premium fuel has a point initial distillation of 32 ° C and a final distillation point of 217 ° C; it includes in volume:

• 29% aromatic
• 13% olefins
• 58% of saturated compounds (paraffins + naphthenics).

The additives are added to the fuel so as to obtain a concentration, by weight of active material in the additive fuel, specified for each example in Table II below which gives the results obtained. TABLE II ADDITIVE FUEL ADDITIVE QUANTITY ORI AT THE END OF THE TEST ORD IN RELATION TO FUEL ONLY 2000 rpm 3500 rpm 2000 rpm 3500 rpm * Fuel only 0 ppm 5.6 4.7 Fuel + Formula F1 660 ppm 2.5 2.0 3.1 2.7 * Fuel + Formula F2 600 ppm 4.1 4.0 1.5 0.7 660 ppm 4.0 3.9 1.6 0.8 * Fuel + Formula F3 800 ppm 7.2 4.9 - 1.6 - 0.9 Fuel + Formulation F4 900 ppm 5.2 4.5 0.4 0.2 800 ppm 5.0 4.3 0.6 0.4 * Comparison

EXAMPLE 6

• 27 % d'aromatiques
• 14 % d'oléfines
• 59 % de composés saturés (paraffines + naphténiques).

A new series of tests is carried out in order to evaluate the control properties of the increase in octane requirement of the additive formulations prepared in Example 4. The tests were carried out by following the procedure described in Example 5. In these examples, the duration of the tests was set at 100 hours and the fuel used is a fuel with lead alkyl additive to 0.15 g of lead per liter, comprising by volume:

• 27% aromatics
• 14% olefins
• 59% of saturated compounds (paraffins + naphthenics).

This fuel, with an engine octane rating of 86 and a research octane rating of 99, has an initial distillation point of 34 ° C and a final distillation point of 185 ° C.

The compositions are added to the fuel so as to obtain a concentration, by weight of the active material in the additive fuel specified for each example in Table III below which gives the results obtained: TABLE III ADDITIVE FUEL ADDITIVE QUANTITY ORI AT THE END OF THE TEST ORD IN RELATION TO FUEL ONLY 2000 rpm 3500 rpm 2000 rpm 3500 rpm * Fuel only 0 ppm 3.8 5.0 Fuel + Formula F1 660 ppm 1.6 3.5 2.2 1.5 Fuel + Formula F5 660 ppm 3.1 2.0 0.7 3.0 * Fuel + Formula F2 660 ppm 3.7 4.3 0.1 0.7 * Comparison

EXAMPLE 7

The “carburetor” detergency properties of the formulations F1 and F2 prepared in Example 4 are evaluated. The engine test procedure is carried out according to European standard R5-CEC-F03-T-81. The results are expressed in terms of merit from zero to ten. A merit 10 corresponds to a clean carburetor and a merit 0 to a very dirty carburetor. The formulations are added to the fuel so as to obtain a concentration by weight of active material in the additive fuel specified for each example in Table IV below which gives the results obtained: TABLE IV ADDITIVE FUEL ADDITIVE QUANTITY DESERVED * Fuel only 0 ppm 4.1 Fuel + Formula F1 660 ppm 9.7 * Fuel + Formula F2 660 ppm 9.6 * Comparison

The fuel used in these assessments is an unleaded premium fuel with an engine octane rating of 85.3 and a research octane rating of 96.7. This premium fuel has an initial distillation point of 36 ° C and a final distillation point of 203 ° C.

• 48,5 % de composés saturés (paraffines + naphténiques)
• 9,8 % d'oléfines
• 28,7 % d'aromatiques
• 13 % de méthyltertiobutyléther.

This premium fuel includes in volume:

• 48.5% saturated compounds (paraffins + naphthenics)
• 9.8% olefins
• 28.7% aromatics
• 13% methyltertiobutylether.

EXAMPLE 8

A new series of tests is carried out so as to evaluate the "carburetor" detergency properties of the formulations F1 and F2 prepared in Example 4.

• 32 % d'aromatiques
• 12 % d'oléfines
• 56 % de composés saturés (paraffines + naphténiques).

The tests were carried out by following the procedure indicated in Example 7. The fuel used in these tests is a premium fuel additive in lead alkyls at 0.15 g of lead per liter, comprising by volume:

• 32% aromatics
• 12% olefins
• 56% saturated compounds (paraffins + naphthenics).

This engine octane fuel of 86 and research octane fuel of 96, has an initial distillation point of 31 ° C and a final distillation point of 202 ° C.

The formulations are added to the fuel so as to obtain a concentration, by weight of active material in the additive fuel, specified for each example in Table V below which gives the results obtained: TABLE V ADDITIVE FUEL ADDITIVE QUANTITY DESERVED * Fuel only 0 ppm 4.2 Fuel + Formula F1 660 ppm 9.7 * Fuel + Formula F2 660 ppm 9.7 * Comparison

EXAMPLE 9

The “injector” detergency properties of the formulations F1 and F2 prepared in Example 4 are evaluated.

The engine test procedure is carried out by following the IFP-TAE I 87 method established by the French Petroleum Institute as described below.

• 15 minutes de fonctionnement à 3000 tr/min sous une charge de 18 kiloWatt (kW)
• 45 minutes d'arrêt moteur.

The tests are carried out on a Peugeot XU5JA engine bench following a cyclic procedure with a total duration of 150 hours corresponding to the repetition of the following cycle:

• 15 minutes of operation at 3000 rpm under a load of 18 kiloWatt (kW)
• 45 minutes of engine shutdown.

The flow rate of each injector is measured at the start and end of the test in order to assess the percentage of flow restriction induced by fouling of the injectors.

• 31,5 % d'aromatiques
• 18,8 % d'oléfines
• 49,7 % de composés saturés (paraffines + naphténiques).

The fuel used in these tests is a super fuel additive in lead alkyls to 0.4 g of lead per liter, comprising by volume:

• 31.5% aromatics
• 18.8% olefins
• 49.7% of saturated compounds (paraffins + naphthenics).

This engine octane fuel of 85.7 and research octane of 97.5 has an initial distillation point of 33 ° C and a final distillation point of 197 ° C.

The formulations are added to the fuel so as to obtain a concentration, by weight of active material in the additive fuel, specified for each example in Table VI below which gives the results obtained: TABLE VI ADDITIVE FUEL ADDITIVE QUANTITY PERCENTAGE OF RESTRICTION INJECTOR FLOW AT 150 HOURS (MEASUREMENT AT 6000 rpm) * Fuel only 0 ppm 18.6% Fuel + Formula F1 660 ppm 0.2% * Fuel + Formula F2 660 ppm 0.3% * Comparison

EXAMPLE 10

A series of tests is carried out so as to evaluate the detergency properties "intake valves" of the formulations F1, F2, F3 and F4 prepared in Example 4.

The following engine test procedure is that described in the literature published by S.A.E. (English initials of Society of Automotive Engineers) under the reference SAE 892121 (1989).

The tests are carried out on a Honda generator equipped with a generator (240 Volt, 5500 Watt) driven by a twin-cylinder engine of 359 cm ³ with 4 times and tumbled valves.

• 1 heure de fonctionnement avec un débit génératrice de 1 500 W (quart de charge)
• 1 heure de fonctionnement avec un débit génératrice de 2 500 W (demi-charge).

Each test is carried out for a period of 80 hours according to the following cyclic procedure:

• 1 hour of operation with a generating flow of 1,500 W (quarter load)
• 1 hour of operation with a generating flow of 2,500 W (half load).

At the start of each test, the engine is conditioned with new valves that are weighed. At the end of the test, the valves are dismantled, washed with hexane, dried, then weighed after physical removal (by scraping) of the deposits formed on the valve on the combustion chamber side. The results presented below give the average of the deposits by weight relative to a valve, calculated from the weight of deposits measured, on the tulip of each intake valve, by difference between the weight of said new valve and the weight of said valve at the end of each test after removal of deposits on the combustion chamber side.

The fuel used in these assessments is an unleaded premium fuel identical to that described in Example 5.

The formulations are added to the fuel so as to obtain a concentration, by weight of active material in the additive fuel, specified for each example in Table VII below giving the results obtained. TABLE VII ADDITIVE FUEL ADDITIVE QUANTITY AVERAGE DEPOSITS IN mg PERCENTAGE REDUCTION OF DEPOSITS / FUEL ONLY * Fuel only 0 ppm 82 - Fuel + Formula F1 660 ppm 4 95% * Fuel + Formula F2 660 ppm 5 94% * Fuel + Formula F3 800 ppm 4 95% Fuel + Formulation F4 800 ppm 4 95% * Comparison

EXAMPLE 11

The anti-corrosion properties of Formulations F1 to F4 prepared in Example 4 are evaluated. The tests consist in determining the extent of the corrosion produced on samples of polished ordinary steel, in the presence of water, following the modified ASTM D 665 standard (temperature 32.2 ° C, duration 20 hours).

The results are expressed as a percentage (%) of the surface of the corroded test piece after 20 hours. The fuel is the same as that used in Example 5.

The amount of composition is added to the fuel so as to obtain a concentration, by weight of active material in the additive fuel, specified for each example in Table VIII below giving the results obtained: TABLE VIII ADDITIVE FUEL ADDITIVE QUANTITY % OF CORROSIVE AREA * Fuel only 0 ppm 100 Fuel + Formula F1 660 ppm 0 * Fuel + Formula F2 660 ppm 0 * Fuel + Formula F3 800 ppm 5 Fuel + Formulation F4 800 ppm 0 * Comparison

EXAMPLE 12

• . Température limite de filtrabilité    : - 3 °C
• . Point initial de distillation    : 162 °C
• . Point 95 % de distillation    : 366 °C
• . Masse volumique à 15 °C    : 0,8331
• . Indice de cétane calculé    : 50,4

Tests are carried out so as to evaluate the anti-corrosion properties of the formulations according to the invention prepared in Example 4. The tests are carried out in a similar manner to that described in Example 11 (temperature 60 ° C, duration 20 hours) in a Diesel fuel. The main characteristics of the diesel fuel used are:

• . Filterability limit temperature: - 3 ° C
• . Initial distillation point: 162 ° C
• . 95% distillation point: 366 ° C
• . Density at 15 ° C: 0.8331
• . Calculated cetane number: 50.4

The quantity of composition is added to the fuel so as to obtain a concentration, by weight of active material in the additive fuel, specified for each example in Table IX below summarizing the results obtained: TABLE IX ADDITIVE FUEL ADDITIVE QUANTITY % OF CORROSIVE AREA * Fuel only 0 ppm 100 Fuel + Formula F1 660 ppm 0 * Fuel + Formulation F4 900 ppm 0 * Comparison

Analysis of the results obtained in the previous examples shows that the formulations according to the present invention make it possible to very significantly limit the increase in octane requirement of spark-ignition engines and has qualities of detergent additives for the intake system as well than anti-corrosion.

These compositions used in a diesel fuel also have anti-corrosion properties.

Claims (9)

1. Additive formulation, particularly for fuels, characterized in that it comprises at least one constituent (A) and at least one constituent (B), said constituent (A) consisting of at least one composition incorporating products resulting from the reaction of maleic anhydride on at least one polyoxyalkylene glycol or glycol monoether (E) having a molecular weight from 500 to 2500 and complying with the general formula (I) :
   
           (I)    R¹-O-(R²-O)_n-H
   
   in which R¹ represents an alkyl, aryl, arylalkyl or alkylaryl group having 1 to 30 carbon atoms and R² is an alkylene group having 2 to 5 carbon atoms of general formula (II) :
   
           (II)    -CH₂-CR³H-
   
   in which R³ represents a hydrogen atom, a methyl group, an ethyl group or a propyl group and n is a number from 1 to 60, said reaction being performed at a temperature of approximately 100°C to approximately 210°C with a molar ratio of compound (E) to maleic anhydride of appproximately 1.5 : 1 to approximately 5 : 1 and for a time sufficient to ensure that the products obtained have a corrected acid number of approximately 3000 to approximately 30,000, and said constituent (B) consists of at least one detergent-dispersnat product chosen from within the group formed by

   1)mixtures of polybutenes and polyisobutylene-amines,

   2) the products resulting from the reaction in a first stage of at least one succinic derivative chosen from within the group formed by alkenyl succinic anhydrides and polyalkenyl succinic anhydrides a number average molecular weight from 200 to 3000 on at least one 1-(2-hydroxyethyl)-imidazoline sustituted in the 2-position by a straight or branched alkyl or alkenyl radical having 1 to 25 carbon atoms, the imidazoline/succinic derivative molar ratio being 0.1:1 to 0.9:1, said stage being performed under conditions such that formation and elimination takes place of at least 0.15 mole of water per mole of imidazoline used; and in a second stage the reaction of the product from the first stage on at least one polyamine complying with one of the following general formulas:

   

   

   in which R³ represents a hydrogen atom or a hydrocarbon group having 1 to 60 carbon atoms, Z is chosen from among the groups -O- and -NR⁵-, in which R⁵ represents a hydrogen atom or a hydrocarbon group having 1 to 60 carbon atoms, R³ and R⁵ can form together with the nitrogen atom to which they are bonded a heterocycle, each of the R⁴ independently represents a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms, p is an integer from 2 to 6, m is an integer from to 10 when Z is -NR⁵- and an integer from 2 to 10 when Z is -O-, D,E,F and G, which can be the same or different, each represent a divalent hydrocarbon group having 2 to 6 carbon atoms, a is an integer from 1 to 60, b and c, which can be the same or different, are each zero or an integer from 1 to 50 and the sum a + b + c is an integer from 1 to 60, the polyamine quantity reacted being at least 0.1 mole per mole of succinic derivative introduced in the first stage and

   3) the products resulting from the reaction, under reaction water formation and elimination conditions, of at least one succinic derivative chosen within the group formed by alkenyl succinic acids and anhydrides and polyalkenyl succinic acids and anhydrides on at least one amine of general formula (III)

   said formulation further containing at least one constituent (C) chosen from within the group formed by mineral or synthetic lubricating oils and polyglycols, soluble in said fuel, of number average molecular weight 480 to 2100 and of general formula (V) :
   
           (V)    HO-R-(-O-R-)_x-O-R-OH
   
   in which each of the R groups independently represents a hydrocarbon group having 2 to 6 carbon atoms and x represents the average degree of polymerization.
2. Formulation according to claim 1, wherein the constituent (B) is chosen from within the group formed by the products resulting from the reaction in a first stage of at least one succinic derivative chosen from within the group formed by alkenyl succinic or polyalkenyl succinic anhydrides having a number average molecular weight of 200 to 3000 on at least one 1-(2-hydroxyethyl)-imidazoline substituted in the 2-position and chosen from within the group formed by 1-(2-hydroxyethyl)-2-heptadecenyl imidazoline and 1-(2-hydroxyethyl)-2-methyl imidazoline; and in a second stage the reaction of the product resulting from the first stage on at least one polyamine complying with the general formula (III):

   

   in which R³ and R⁴ in each case represent a hydrogen atom, Z represents a -NR⁵- group, in which R⁵ represents a hydrogen atom, p is equal to 2 and m is an integer from 1 to 5.
3. Formulation according to claim 1 wherein the constituent (B) is chosen from within the group formed by the products resulting from the reaction in a first stage of at least one succinic derivative chosen from within the group formed by alkenyl succinic or polyalkenyl succinic anhydrides of number average molecular weight 200 to 3000 on at least one 1-(2-hydroxyethyl)-imidazoline substituted in the 2-position and chosen from within the group formed by 1-(2-hydroxyethyl)-2-heptadecenyl imidazoline and l-(2-hydroxyethyl)-2-methyl imidazoline; and in a second stage the reaction of the product from the first stage on at least one polyamine complying with the general formula (IV):

   

   in which R³ and R⁵ in each case represents a hydrogen atom, D,E,F and G, which can be the same or different, in each case represents a divalent hydrocarbon group having 2 to 4 carbon atoms, a is an integer from 1 to 60 and b and c are equal to zero or a is an integer from 1 to 59, c is zero or an integer such that the sum a + c is 1 to 59 and b is a integer from 1 to 50, the sum a + b + c being in all cases an integer from 1 to 60.
4. Formulation according to claim 1, wherein the constituent (B) is chosen from within the group formed by the products resulting from the reaction of at least one succinic derivative chosen from within the group formed by alkenyl succinic or polyalkenyl succinic anhydrides of number average molecular weight 200 to 3000 on at least one amine of general formula (III), in which R³ and R⁴ in each case represents a hydrogen atom, Z represents a -NR⁵- group, in which R⁵ represents a hydrogen atom, p is equal to 2 and m is an integer from 1 to 5, said reaction being performed at a temperature of approximately 120°C to approximately 200°C with an amine to succinic derivative molar ratio of approximately 0.9:1 to approximately 1.2:1.
5. Formulation according to anyone of the claims 1 to 4, wherein the constituent (C) is a polyglycol having a polydispersity index of approximately 1 to approximately 1.25 and of general formula (V), in which each of the groups R independently represents a straight or branched alkylene group having 2 to 4 carbon atoms and preferably an ethylene or propylene group.
6. Use of an additive formulation according to any one of the claims 1 to 5 as an additive for a fuel based on hydrocarbons or a mixture of hydrocarbons and at least one oxygen compound chosen from within the group formed by alcohols and ethers.
7. Use of an additive formulation according to any one of the claims 1 to 5 as an additive for a fuel used in controled ignition engines.
8. Use according to claims 6 or 7, wherein 10 to 10,000 ppm by weight of the additive formulation is added to the fuel.
9. Use according to anyone of the claims 6 to 8, wherein the formulation comprises the constituents (A) and (B) in a (A)/(B) weight ratio of approximately 0.05:1 to approximately 2:1. the constituent (C) in a weight quantity such that the (B)/(C) weight ratio is approximately 0.1:1 to approximately 5:1.