EP3728524A1

EP3728524A1 - Use of crosslinked polymers for lowering the cold filter plugging point of fuels

Info

Publication number: EP3728524A1
Application number: EP18815750.7A
Authority: EP
Inventors: Inigo Gonzales; Ana-Maria CENACCHI-PEREIRA
Original assignee: Total Marketing Services SA
Current assignee: TotalEnergies Onetech SAS
Priority date: 2017-12-21
Filing date: 2018-12-17
Publication date: 2020-10-28
Also published as: WO2019121485A1; US20210095217A1; FR3075813A1; FR3075813B1

Abstract

The present invention concerns the use, for lowering the cold filter plugging point of a fuel composition, of one or more crosslinked polymers comprising at least one unit of the following formula (I): in which R₁ represents a hydrogen atom or a methyl group; E represents -O-CO-, or -CO-O- or -NH-CO- or -CO-NH-; and G represents a C₁ to C₃₄ alkyl group; said copolymer having a crosslinking rate of between 0.5 mol% and 30 mol%. The invention also concerns additive compositions containing such a polymer, and fuel compositions with such polymers as additives, in combination with a cold flow improver (CFI) chosen from the copolymers and terpolymers of ethylene and vinyl and/or acrylic ester(s).

Description

Use of cross-linked polymers to lower the filterability limit temperature of fuels

The present invention relates to the use of particular cross-linked polymers for lowering the filterability limit temperature of fuels during storage and / or their use at low temperatures.

The present invention also relates to additive compositions (or "additive packages") containing these polymers, as well as fuel and fuel compositions supplemented with such polymers in combination with a cold-flow additive (CFI).

STATE OF THE PRIOR ART Fuels or fuels containing paraffinic compounds, especially compounds containing n-alkyl, isoalkyl or n-alkenyl groups, such as paraffin waxes, are known to have deteriorated flow properties at low temperatures. temperature, typically below 0 ° C. In particular, it is known that the middle distillates obtained by distillation from crude oils of petroleum origin such as diesel or heating oil, contain different amounts of n-alkanes or n-paraffins according to their origin. These compounds tend to crystallize at low temperatures, clogging pipes, pipes, pumps and filters, for example in motor vehicle fuel systems. In winter or under conditions of use of fuels or fuels below 0 ° C, the phenomenon of crystallization of these compounds can lead to the decrease of the flow properties of fuels and, consequently, cause difficulties during their transport, storage and / or use. Cold operability of fuels or fuels is a very important property, especially for starting cold engines. If paraffins are crystallized at the bottom of the tank, they can be driven to start in the fuel system and particularly clog filters and prefilters arranged upstream of the injection systems (pump and injectors). Similarly, for the storage of domestic fuel oils, if paraffins precipitate at the bottom of the tank, they can be driven and obstruct the pipes upstream of the pump and the boiler supply system (nozzle and filter).

These problems are well known in the field of fuels, and many additives or additive mixtures have been proposed and marketed to reduce the size of the paraffin crystals and / or change their shape and / or prevent them from forming. The smallest crystal size possible is preferred because it minimizes the risk of clogging or filter clogging.

The usual flow improvers known as cold flow improvers (CFI) are generally co- and ter-polymers of ethylene and vinyl ester (s) and / or or acrylic (s), used alone or as a mixture. These Cold Flow Conditioning Additives (CFI), intended to lower the Temperature Limit of Filtration (TLF), inhibit crystal growth at low temperatures by promoting the dispersion of paraffin crystals; these are, for example, polymers of ethylene and vinyl acetate and / or vinyl propionate (EVA or EVP), also commonly known as TLF additives. This type of additive, widely known by those skilled in the art, is systematically added to conventional middle distillates at the refinery outlet. These additive distillates are used as fuel for diesel engines or as heating fuel. Additional quantities of these additives can be added to the fuels sold at service stations, in particular to meet the so-called "Big Cold" specifications.

To improve the TLF of the distillates, it is known to add to these CFI additives additional additives or "boosters" having the function of acting in combination with the CFI additives so as to increase efficiency. The prior art extensively describes such combinations of additives.

By way of example, mention may be made of US Pat. No. 3,254,527, which describes a distillate distillation distillate of between 177 and 400 ° C. containing an additive consisting of from 90 to 10% by weight of an ethylene copolymer comprising from 10 to 30% of vinyl acetate units of molar mass by weight of between 1000 and 3000 g. mol ¹ and from 10 to 90% by weight of a lauryl polyacrylate and / or a lauryl polymethacrylate of molar mass by weight ranging from 760 to 100,000 g. mol ¹ .

EP0857776 proposes to use alkylphenol-aldehyde resins derived from the condensation of alkylphenol and aldehyde in combination with copolymers or terpolymers ethylene / vinyl ester, to improve the fluidity of mineral oils.

Patent application WO 2008/006965 describes the use of a combination of a homopolymer obtained from an olefinic carboxylic acid ester of 3 to 12 carbon atoms and a fatty alcohol comprising a chain of more of 16 carbon atoms and possibly an olefinic double bond and a cold-cooling additive (CFI) of the EVA or EVP type, to increase the effectiveness of the CFI additives by amplifying their effect on the TLF.

The patent application WO 2016/128379 describes the use, as cold-holding additive of a fuel or fuel, of a block copolymer comprising:

(i) a block A consisting of a chain of structural units derived from one or more α, β-unsaturated acrylate or alkyl methacrylate monomers,

(ii) a block B consisting of a chain of structural units derived from one or more α, β-unsaturated monomers containing at least one aromatic ring.

This additive is especially useful as a TLF booster in combination with a cold-flow additive (CFI).

Due to the diversification of fuel sources and For fuel, there is still a need to find new additives to lower the filterability limit temperature of fuels.

This need is particularly important for fuels comprising one or more paraffinic compounds, for example compounds containing n-alkyl, isoalkyl or n-alkenyl groups exhibiting a tendency to crystallize at low temperature.

In particular, distillates used in fuels are increasingly derived from more complex refining operations than those resulting from the direct distillation of petroleum, and can come in particular from cracking, hydrocracking and catalytic cracking processes. visbreaking processes. With the increasing demand for diesel fuels, the refiner tends to introduce into these fuels cuts more difficult to exploit, such as the heaviest cuts from cracking and visbreaking processes which are rich in long-chain paraffins.

In addition, synthetic distillates resulting from the transformation of gas such as those resulting from the Fischer Tropsch process, as well as distillates resulting from the treatment of biomasses of plant or animal origin, such as in particular NexBTL and distillates comprising oil esters. plants or animals have appeared on the market, and constitute a new range of products that can be used as a basis for formulating fuels and / or household fuels. These products also include long chain paraffinic hydrocarbons.

In addition, the arrival of new crude oils on the market, much richer in paraffins than those commonly refined and whose filterability temperature of distillates from direct distillation was hardly improved by the conventional filterability additives in the same way than those previously mentioned.

It has been found that the cold-holding properties of the distillates obtained by combining the old bases and these new The sources were hardly improved by the addition of conventional filterability additives, inter alia because of the large presence of long-chain paraffins and the complex distribution of paraffins in their composition. It has been noted in fact in these new combinations of distillates, discontinuous paraffin distributions, in the presence of which known filterability additives are not always sufficiently effective.

There is therefore a need to adapt the cold-holding additives to these new types of bases for fuels, considered particularly difficult to treat.

The present invention applies to fuels containing not only conventional distillates such as those derived from the direct distillation of crude oils, but also bases derived from other sources, such as those described above.

Thus, the object of the present invention is to propose novel additives and concentrates containing them which may advantageously be used as additives to improve the cold-holding properties of these fuels, when they are stored and / or when they are used low temperature, typically below 0 ° C.

The object of the present invention is to propose new additives for fuels and fuels, and concentrates containing such additives, acting on the Temperature Limit of Filtration (TLF).

Finally, another object of the invention is to provide a fuel or fuel composition having improved cold-holding properties, particularly at temperatures below 0 ° C, preferably below -5 ° C. OBJECT OF THE INVENTION

The applicant has now discovered that particular crosslinked homopolymers or copolymers, as described hereinafter, have unexpected properties for lowering the temperature. filterability limit for fuel and fuel compositions, including those that are particularly difficult to treat.

The present invention thus relates to the use, for lowering the filterability limit temperature of a fuel or fuel composition, of one or more crosslinked polymers comprising at least one unit of formula (I) below:

in which

R 1 represents a hydrogen atom or a methyl group,

E represents -O-CO-, or -CO-O- or -NH-CO- or -CO-NH-, and

G represents a C1-C34 alkyl group,

said copolymer having a degree of crosslinking, corresponding to the molar amount of crosslinking agent relative to the total molar amount of monomers in the polymer, crosslinking agent not included, in the range of 0.5% to 30% .

According to a preferred embodiment, the polymer defined above is used as a so-called "TLF booster" additive, that is to say in combination with a flow-enhancing additive or cold-flow additive (in English "cold"). flow improvers "or CFI), which improves performance.

The invention also relates to an additive composition comprising such a polymer in combination with a cold-cooling additive as described hereinafter, as well as an additive concentrate comprising such a composition. The cold-cooling additive chosen from copolymers and terpolymers of ethylene and of vinyl ester (s) and / or acrylic (s), alone or as a mixture.

The invention also relates to a composition of fuel or fuel, comprising:

(1) at least one hydrocarbon cut from one or more sources selected from the group consisting of mineral (preferably petroleum), animal, plant and synthetic sources,

(2) at least one crosslinked polymer as defined above, and

(3) at least one cold-cooling additive selected from copolymers and terpolymers of ethylene and of vinyl ester (s) and / or acrylic (s).

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

In what follows, and unless otherwise indicated, the boundaries of a domain of values are included in this field, especially in the expressions "between" and "from ... to ...".

In addition, the expressions "at least one" and "at least" used in the present description are respectively equivalent to the terms "one or more" and "greater than or equal to".

Finally, in a manner known per se, the term compound C _N denotes a compound containing in its chemical structure N carbon atoms. DETAILED DESCRIPTION

The crosslinked polymer:

The invention uses a crosslinked polymer, comprising at least one unit of formula (I) below:

in which

R 1 represents a hydrogen atom or a methyl group,

E represents -O-CO-, or -CO-O- or -NH-CO- or -CO-NH-,

G represents a C1-C34 alkyl group.

The group E of the formula (I) is chosen from:

- E = -O-CO-, it being understood that E is then connected to the vinyl carbon by the oxygen atom;

- E = -CO-O-, provided that E is then connected to the vinyl carbon by the carbon atom;

- E = -NH-CO-, it being understood that E is then connected to the vinyl carbon by the nitrogen atom; and

- E = -CO-NH-, provided that E is then connected to the vinyl carbon by the carbon atom.

According to a first embodiment, the group E of the formula (I) is chosen from: -O-CO- and -NH-CO-, it being understood that the group E = -O-CO- is connected to the vinyl carbon by the oxygen atom and that the group E = -NH-CO- is connected to the vinyl carbon by the nitrogen atom. In this embodiment, the group E of the formula (I) is preferably the group -O- CO-.

According to a second embodiment, the group E of the formula (I) is chosen from: -CO-O- and -CO-NH-, it being understood that the group E is connected to the vinyl carbon by the carbon atom. In this embodiment, the group E of the formula (I) is preferably the -CO-O- group.

According to a particularly preferred embodiment, the group E is a group -CO-O-, E being connected to the vinyl carbon by the carbon atom.

The group G of the formula (I) is a C 1 to C ₃₄ alkyl group, preferably a C ₄ to C ₃₄ alkyl radical, preferably a C ₄ to C ₃₀ alkyl radical, more preferably a C ₆ to C ₂₄ alkyl radical, more preferably in Cs to C ₂₂ . The alkyl radical is a linear or branched radical, cyclic or acyclic, preferably acyclic. This alkyl radical can comprise a linear or branched part and a cyclic part.

The group G of formula (I) is advantageously a linear or branched C 1 to C ₃₄ , preferably C ₄ to C ₃₄ , more preferably C ₄ to C ₃₀ , more preferably C ₆ to C _24, alkyl acyclic radical. more preferably Cs to C22, and more preferably C12 to C14 or C14 to C22. The embodiment in which the group G is a linear or branched C ₁₂ to C ₁₄ acyclic alkyl radical is particularly preferred.

Mention may be made, in a nonlimiting manner, of alkyl groups such as butyl, octyl, decyl, dodecyl, ethyl-2-hexyl, isooctyl, isodecyl and isododecyl, and alkyl groups. at C 14, C 1-6 alkyl groups and C _1-6 alkyl groups.

According to a particularly preferred embodiment, the group E is a group -CO-O-, E being connected to the vinyl carbon by the carbon atom, and the group G is a linear or branched acyclic alkyl radical C1 to _C34. , preferably C ₄ -C _30, more preferably C ₆ -C _24, more preferably Cs to C _22, more preferably C ₁₂ -C ₁₄ or -C s to C _22. The embodiment in which the group G is a linear or branched C ₁₂ to C ₁₄ acyclic alkyl radical is particularly preferred.

The units according to this embodiment correspond to those resulting from monomers chosen from acrylates and methacrylates of C 1 to C _34, preferably C ₄ to C ₃₀ , more preferably C ₆ to C ₂₄ , even more preferentially in Cs to C ₂₂ , and more preferably in C12 to C14 or in C s to C22. The crosslinked polymer may be a homopolymer or a copolymer.

In this case of a copolymer, the polymer according to the invention may comprise several (at least two) different units of formula (I) as described above and / or additional units, different from the units of formula (I) above.

Such additional units are preferably derived from polar monomers, such as in particular from one or more polar-substituted vinyl monomers.

Preferred polar monomers include:

2-phenoxyethylacrylate:

1 -vinylimidazole:

N-vinylpyrrolidone:

The copolymer according to the invention advantageously contains at least 50 mol% of units of formula (I), preferably at least 70 mol%. Preferably, the copolymer contains from 50 to 80 mol% of units of formula (I).

When the polymer according to the invention is a copolymer, it may be chosen from block copolymers and random copolymers, preferably random copolymers.

The polymer according to the invention has the particularity of being crosslinked. The degree of crosslinking, corresponding to the quantity in moles of crosslinking agent relative to the total amount by mole of monomers of the polymer, crosslinking agent not included, is from 0.5% to 30%, preferably from 1% to 20%, more preferably from 2% to 10%, and even better from 3% to 6%.

The crosslinking agent may be any compound capable of allowing the crosslinking of polymers comprising units of formula (I) as described above. Many crosslinking agents exist, and are well known to those skilled in the art.

According to a preferred embodiment, the crosslinking agent is chosen from di-vinyl compounds, and more preferentially from the diacrylates and dimethacrylates of formula (III) below:

with

R representing a hydrocarbon chain comprising from 2 to 16 and preferably from 3 to 12 carbon atoms, which may be interrupted by one or more heteroatoms chosen from N and O, and which may be substituted with one or more -OZ groups with Z representing a hydrogen atom or a C ₁ -C ₄ alkyl radical, and

R ₂ and R ₃ represent, independently of one another, a hydrogen atom or a methyl group.

Nonlimiting examples of particularly preferred crosslinking agents include:

1,6-hexanediol dimethacrylate, of formula:

di (ethylene glycol) dimethacrylate, of formula:

glycerol dimethacrylate, of formula:

1,6 hexanediol diacrylate, of formula:

di (ethylene glycol) diacrylate, of formula: the 1,6 hexanediol ethoxylate diacrylate of formula:

The polymer employed in the present invention may be obtained by homopolymerization or copolymerization of at least one monomer corresponding to the following formula (II):

in which

R 1, E and G are as defined above, the preferred variants of R 1, E and G according to formula (I) described above being also preferred variants of formula (II).

When the group E of the monomer of formula (II) is the group -O-CO-, it being understood that the group -O-CO- is connected to the vinyl carbon by the oxygen atom, the monomer of formula (II) is preferably selected from alkyl vinyl esters Ci-C34, preferably C ₄ to C 30, more preferably C ₆ to C 24, more preferably C ₈ to C22, more preferably C12-C14 or Ci ₈ at C22 and even more preferably at C12 to C14. The alkyl radical of the alkyl vinyl ester is linear or branched, cyclic or acyclic, preferably acyclic.

Among the alkyl vinyl ester monomers, mention may be made, for example, of vinyl octanoate, vinyl decanoate, vinyl dodecanoate, vinyl tetradecanoate, vinyl hexadecanoate, vinyl octodecanoate and docosanoate. vinyl, 2-ethylhexanoate vinyl.

When the group E of the monomer of formula (II) is the group -CO-O-, it being understood that the group -CO-O- is connected to the vinyl carbon by the carbon atom, the monomer of formula (II) is preferably selected from acrylates or methacrylates of alkyl to C34, preferably C ₄ to C 30, more preferably C ₆ to C 24, more preferably Cs to C22 and more preferably C12 to C14, or Cis at C22, and even more preferably at C12 to C14. The alkyl radical of the acrylate or methacrylate is linear or branched, cyclic or acyclic, preferably acyclic.

Among the alkyl (meth) acrylates that can be used as monomers in the manufacture of the polymer of the invention, mention may be made, by way of non-limiting examples: n-octyl acrylate, n-octyl methacrylate, n-decyl acrylate, methacrylate, n-decyl, n-dodecyl acrylate, n-dodecyl methacrylate, ethyl-2-hexyl acrylate, ethyl-2-hexyl methacrylate, isooctyl acrylate, methacrylate, isooctyl, isodecyl acrylate, isodecyl methacrylate, alkyl acrylates, C _{1 2} to ₄ or a 1 is C to C22 alkyl methacrylates of C 12 to C i ₄ or i C 8 -C _22. It is particularly preferred to employ alkyl acrylate, C 12 to C i ₄ alkyl methacrylates and C 12 to C i ₄ alkyl acrylates, C is -C ₂₂ alkyl methacrylates, C is at C22.

It is understood that it would not go beyond the invention if the polymer according to the invention was obtained from monomers different from those of formula (II) above, insofar as the final polymer corresponds to a crosslinked polymer as defined above. For example, it would not go beyond the invention, if one obtained the polymer by polymerization of different monomers, followed by post-functionalization. For example, the units of formula (I) can be obtained from acrylic acid, by transesterification reaction.

The polymer according to the invention can be prepared according to any known method of polymerization. The various techniques and conditions of polymerization and crosslinking are widely described in the literature and fall within the general knowledge of those skilled in the art.

The polymerization is, advantageously, a controlled radical polymerization; for example, by atom transfer radical polymerization (ATRP in English "Atom Transfer Radical Polymerization"); the radical polymerization by nitroxide (NMP in English "Nitroxide-mediated polymerization"); degenerative transfer processes (degenerative transfer processes) such as degenerative iodine transfer polymerization (ITRP-iodine polymerization ") or radical polymerization by reversible addition-fragmentation chain transfer (RAFT) (Reversible Addition-Fragmentation Chain Transfer); polymerizations derived from ATRP such as polymerizations using initiators for the continuous regeneration of the activator (ICAR -Initiators for continuous activator regeneration) or using electron-regenerated activators regenerated by electron (ARGET) transfer ").

The reversible Addition-Fragmentation Chain Transfer (RAFT) radical polymerization is a living radical polymerization technique. The RALT technique was discovered in 1988 by the Australian scientific research organization CSIRO (J. Chiefari et al., Macromolecules, 1998, 31, 5559). The RALT technique has very rapidly been the subject of intensive research by the scientific community as it allows the synthesis of macromolecules with complex architectures, including structures in blocks, grafts, combs or even stars. by controlling the molecular weight of the macromolecules obtained (G. Moad et al., Aust J. Chem, 2005, 58, 379). RALT polymerization can be applied to a very broad range of vinyl monomers and under various experimental conditions, including for the preparation of water-soluble materials (McCormick, C. et al., Acc., Chem Res., 2004, 37, 3, 12). ). The RALT method includes the conventional radical polymerization of a substituted monomer in the presence of a suitable chain transfer agent (RALT agent or CTA in English "Chain Transfer Agent"). Commonly used RALT agents include thiocarbonylthio compounds such as dithioesters (J. Chiefari et al., Macromolecules, 1998, 1, 5559), dithiocarbamates (R. T. A. Mayadunne et al.,

Macromolecules, 1999, 32, 6977; M. Destarac et al. , Macromol. Rapid. Common. , 2000, 21, 1035), trithiocarbonates (RTA Mayadunne et al., Macromolecules, 2000, 33, 243) and xanthates (R. Lrancis et al., Macromolecules, 2000, 33, 4699), which operate polymerization by a reversible chain transfer method. The use of a suitable RAFT agent allows the synthesis of polymers having a high degree of functionality and having a narrow distribution of molecular weights, that is to say a low polydispersity index (PDI in English "Polydispersity index") .

Examples of radical radicalization description RAFT include the following documents WO 1998/01478, W01999 / 114 144, WO2001 / 77198, WO2005 / 003 19,

W02005 / 000924.

The crosslinked polymer according to the invention advantageously has a weight average molecular weight (Mw) of between 10 000 and 100 000 g. mol ¹ , preferably between 10,000 and 50,000 g. mol ¹ , and more preferably between 1 000 and 35 000 g. mol ¹ .

The crosslinked polymer according to the invention advantageously has a number-average molecular weight (Mn) of between 2,000 and 16,000 g. mol ¹ .

The average molar masses by number and by weight are measured by Size Exclusion Chromatography (SEC).

Use:

The crosslinked polymer described above is used to lower the temperature limit of filterability of a fuel composition or fuel, in particular, of a composition selected from gas oils, biodiesel, type B _x gas oils and fuel oils preferably, domestic fuel oils (FOD).

The filterability limit temperature, or TLF, is measured according to standard NF EN 1 16.

The fuel or fuel composition is as described below and advantageously comprises at least one hydrocarbon fraction from one or more sources selected from the group consisting of mineral sources, preferably petroleum, animal, vegetable and synthetic. According to a preferred embodiment, the crosslinked polymer according to the invention is used as a TLF booster additive, that is to say in combination with at least one flow-enhancing additive or cold-flow additive (in English "cold"). flow improvers "or CFI).

The cold-flow additive (CFI) is chosen from copolymers and terpolymers of ethylene and of vinyl ester (s) and / or acrylic (s), alone or as a mixture.

In this embodiment, the crosslinked polymer according to the invention is used to amplify the fluidifying effect of the cold-flow additive, by lowering the filterability limit temperature (TLF).

This effect is usually called the "TLF booster" effect insofar as the presence of the crosslinked polymer improves the fluidifying nature of the CFI additive. This improvement is reflected, in particular, by a significant decrease in the TLF of the fuel composition or fuel additive with this combination compared to the same fuel composition or fuel additive only with the CFI additive, at the same rate of treatment. Generally, a significant decrease in the TLF results in a reduction of at least 3 ° C of the TLF according to standard NF EN 1 16.

According to a particularly preferred embodiment, the crosslinked polymer is used to amplify the fluidizing (flow) effect of the cold-flow-making additive (CFI) by improving the temperature limit of filterability (TLF) of the fuel or fuel, the TLF being measured according to standard NF EN 1 16.

The crosslinked polymer may be added to the fuels within the refinery, and / or be incorporated downstream of the refinery, optionally mixed with other additives, in the form of an additive concentrate, also called according to the use "additive package".

The crosslinked polymer is advantageously used in the fuel or fuel at a content of at least 2 ppm by weight, preferably at least 3 ppm by weight, and more preferably at least 5 ppm by weight. ppm by weight, more preferably at a content ranging from 2 to 100 ppm by weight, still more preferably from 3 to 50 ppm by weight and more preferably from 3 to 10 ppm by weight, relative to the total weight of the fuel composition or of fuel. The units mentioned in ppm in the present application correspond to ppm by weight unless otherwise indicated.

The additive composition: The invention also relates to an additive composition comprising a crosslinked polymer as described above, and one or more additive (s) fluidifying (s) cold.

The cold-flow additive (CFI) is chosen from copolymers and terpolymers of ethylene and of vinyl ester (s) and / or acrylic (s), alone or as a mixture. By way of example, mention may be made of copolymers of ethylene and of unsaturated ester, such as ethylene / vinyl acetate (EVA), ethylene / vinylpropionate (EVP), ethylene / vinyl ethanoate (EVE) copolymers ethylene / methyl methacrylate (EMMA), and ethylene / alkyl fumarate described, for example, in US3048479,

US3627838, US3790359, US3961961 and EP261957.

According to a preferred embodiment, the cold-flow-making additive (CFI) is chosen from copolymers of ethylene and of vinyl ester (s), alone or as a mixture, in particular ethylene / vinyl acetate copolymers. (EVA) and ethylene / vinyl propionate (EVP), more preferably ethylene / vinyl acetate copolymers (EVA).

The additive composition may also comprise one or more other additives commonly used in fuels or fuels, different from the cross-linked polymer and cold-flow-reducing additives described above.

The additive composition may typically comprise one or more other additives selected from detergents, anti-corrosion agents, dispersants, demulsifiers, anti-foam agents, biocides, deodorants, procetane additives, friction modifiers, lubricity additives or lubricity additives, combustion assistants (catalytic combustion promoters and soot), anti-sedimentation agents, anti-wear agents and / or conductivity modifiers.

Among these additives, mention may be made in particular of:

a) procetane additives, in particular (but not limited to) selected from alkyl nitrates, preferably 2-ethyl hexyl nitrate, aryl peroxides, preferably benzyl peroxide, and alkyl peroxides, preferably ter-butyl peroxide;

b) anti-foam additives, in particular (but not limited to) selected from polysiloxanes, oxyalkylated polysiloxanes, and fatty acid amides from vegetable or animal oils. Examples of such additives are given in EP 861 882, EP663000, EP736590;

c) detergent and / or anti-corrosion additives, in particular (but not limited to) selected from the group consisting of amines, succinimides, alkenylsuccinimides, polyalkylamines, polyalkylamines, polyetheramines, quaternary ammonium salts and triazole derivatives; examples of such additives are given in the following documents: EP0938535,

US2012 / 00101 12 and WO2012 / 004300.

d) lubricity additives or anti-wear agents, in particular (but not limited to) selected from the group consisting of fatty acids and their ester or amide derivatives, in particular glycerol monooleate, and monocarboxylic acid derivatives and polycyclic. Examples of such additives are given in the following documents: EP680506, EP860494, WO98 / 04656, EP915944, FR2772783, FR2772784.

e) anti-sedimentation additives and / or paraffin dispersants, in particular (but not exclusively) chosen from the group consisting of polyamine-amidated (meth) acrylic acid / alkyl (meth) acrylate copolymers, alkenylsuccinimides of polyamine, phthalamic acid derivatives and double fatty amine chain; alkylphenol resins. Examples of such additives are given in the following documents: EP261959, EP59333 1, EP674689, EP327423, EP512889, EP832172; US2005 / 022363 1;

US5998530; W093 / 14178.

The additive composition may advantageously comprise from 0.3 to 30% by weight of crosslinked polymer as described above, relative to the total weight of the additive composition.

The present invention also relates to an additive concentrate comprising an additive composition as described above, in admixture with an organic liquid. The organic liquid is advantageously inert with respect to the constituents of the additive composition, and miscible with fuels, especially those from one or more sources selected from the group consisting of mineral sources, preferably the petroleum, animal, vegetable and synthetic.

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

The fuel or fuel composition:

The invention also relates to a fuel or fuel composition, comprising:

(1) at least one hydrocarbon cut from one or more sources selected from the group consisting of mineral, animal, plant and synthetic sources,

(2) at least one crosslinked polymer as defined above, and

Mineral springs are preferably oil. The fuel composition according to the invention advantageously comprises the crosslinked polymer (s) in a content of at least 2 ppm by weight, preferably at least 3 ppm, and more preferably at least 5 ppm. ppm, more preferably at a content ranging from 2 to 100 ppm, still more preferably from 3 to 50 ppm, and more preferably from 3 to 10 ppm by weight.

According to a preferred embodiment, the cold-reducing additive (s) is (are) chosen from ethylene / vinyl acetate (EVA), ethylene / vinylpropionate (EVP), ethylene copolymers. vinyl ethanoate (EVE), ethylene / methyl methacrylate (EMMA); and more preferably from ethylene / vinyl acetate (EVA) and ethylene / vinyl propionate (EVP) copolymers; more preferably still among the ethylene / vinyl acetate copolymers (EVA).

The composition advantageously contains at least 20 ppm by weight, preferably at least 50 ppm, advantageously between 20 and 5000 ppm, more preferably between 50 and 1000 ppm by weight of cold-flow additive (s).

The fuels or fuels may be chosen from liquid hydrocarbon fuels or liquid fuels alone or as a mixture. The liquid hydrocarbon fuels or fuels comprise, in particular, middle distillates having a boiling point of between 100 and 500 ° C. These distillates may for example be chosen from distillates obtained by direct distillation of crude hydrocarbons, vacuum distillates, hydrotreated distillates, distillates obtained from catalytic cracking and / or hydrocracking of distillates under vacuum, distillates resulting from ARDS (by atmospheric residue desulphurisation) and / or visbreduction type conversion processes, the distillates resulting from the recovery of Fischer Tropsch cuts, the distillates resulting from the BTL (biomass to liquid) conversion of plant and / or animal biomass, taken alone or in combination, and / or biodiesels of animal and / or vegetable origin and / or oils and / or esters of vegetable and / or animal oils. The sulfur content of the fuels or fuels is preferably less than 5000 ppm by weight, preferably less than 500 ppm, and more preferably less than 50 ppm, or even less than 10 ppm and advantageously without sulfur.

The fuel or fuel is preferably selected from gas oils, biodiesels, gasolines type B _x and fuel oils, preferably domestic fuel oils (FOD).

Diesel fuel of type B _x for a diesel engine (compression engine) means a diesel fuel which contains x% (v / v) of vegetable or animal oil esters (including used cooking oils) converted by a process chemical called transesterification reacting this oil with an alcohol to obtain fatty acid esters (EAG). With methanol and ethanol, fatty acid methyl esters (EMAG) and fatty acid ethyl esters (EEAG) are obtained respectively. The letter "B" followed by a number x ranging from 0 to 100 indicates the percentage of EAG contained in the diesel fuel. Thus, a B99 contains 99% of EAG and 1% of middle distillates of fossil origin, the B20, 20% of EAG and 80% of middle distillates of fossil origin, etc. Thus, the diesel fuels of Bo type are distinguished. which do not contain oxygenated compounds, type Bx gasolines which contain x% (v / v) of vegetable oil esters or fatty acids, most often methyl esters (EMHV or EMAG). When the EAG is used alone in the engines, the fuel is designated by the term B 100.

The fuel or fuel may also contain hydrogenated vegetable oils known to those skilled in the art as HVO (hydrogenated vegetable oil) or HDRD (hydrogenation-derived renewable diesel). .

According to a particular development, the fuel or fuel is selected from gas oils, biodiesels and gas oils type B _x , hydrogenated vegetable oils (HVO), and mixtures thereof.

The fuel or fuel composition may also contain one or more additional additives, different from the cross-linked polymers and cold-flow-reducing additives described above. Such additives may be chosen from detergents, anti-corrosion agents, dispersants, demulsifiers, anti-foam agents, biocides, re-deodorants, procetane additives, friction modifiers, lubricant additives or additives. lubricity, combustion assistants (catalytic combustion promoters and soot), anti-settling agents, anti-wear agents and / or conductivity modifiers.

These additional additives may generally be present in an amount ranging from 50 to 1000 ppm by weight (each).

According to another embodiment of the invention, a method for lowering the filterability limit temperature of a fuel or fuel composition comprises a step of treating said composition with at least one crosslinked polymer as described above, and with one or more cold-flow additive (s) chosen from copolymers and terpolymers of ethylene and of vinyl ester (s) and / or acrylic (s).

According to a preferred embodiment, such a method comprises the successive steps of:

a) determination of an additive composition (s) most suitable for the fuel composition or fuel to be treated and the treatment rate necessary to achieve a maximum value of filterability limit temperature for the specific fuel or fuel composition said additive composition (s) comprising at least cross-linked polymer according to the invention and at least one cold-flow-forming additive (CFI);

b) treating the fuel or fuel composition with the amount determined in step a) of said additive composition (s).

The process according to the invention is typically intended for a fuel or fuel composition as described above.

Step a) is carried out according to any known process and is common practice in the field of fuel additives. This step involves defining a target value and then to determine the improvement that is required to achieve the specification.

In particular, the specification is a maximum TLF according to standard NF EN 1 16. The determination of the amount of additive composition (s) to be added to the fuel or fuel composition in order to reach the specification will be carried out typically by comparison with the composition. fuel or fuel without said additive composition (s).

The cross-linked polymer amount needed to process the fuel or fuel composition may vary depending on the nature and origin of the fuel or fuel, particularly depending on the rate and nature of the paraffinic compounds it contains. The nature and origin of the fuel or fuel may therefore also be a factor to be taken into account for step a).

The above method may also include an additional step after step b) of checking the target reached and / or adjusting the treatment rate with the additive composition (s).

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

EXAMPLES

Example 1 Synthesis of Crosslinked and Noncrosslinked Polymers Containing Reasons of Formula (I)

C 12 / C 14 alkyl methacrylate homopolymer, uncrosslinked

(comparative):

7.0 g (0.0262 mol) of C1 2 / C1 4 alkyl methacrylate monomer are introduced into a 50 ml monocolumn flask followed by 0.299 g (0.00135 mol) of RAFT (2-cyano) 2-propyl benzodithioate) and 4.12 g (4.0 mL) of 1,4-dioxane are added. The monomer concentration is set at 2.0 mol L ¹ . The flask is then degassed for 30 minutes under nitrogen and with magnetic stirring, then sealed. In parallel, 0,0286g (1, 74. 10 ⁴ mol) of AIBN (azobis isobutyronotrile) are introduced into a second flask of 25 ml, and 1, 03 g (l, 0ml) of l, 4-dioxane as the solvent of dissolution. The second flask is in turn degassed for 30 minutes under nitrogen. The AIBN solution is then transferred using a nitrogen purged syringe into the 50 mL flask, preheated to 80 ° C, to initiate polymerization. The reaction is left 24h. After the polymerization is complete, the solvent is evaporated under reduced pressure (55mbar) at 60 ° C to recover the polymer.

Crosslinked C 12 / C 14 alkyl methacrylate homopolymer (in accordance with the invention):

7.0 g (0.0262 mol) of C1 2 / C1 4 alkyl methacrylate monomer are introduced into a 50 ml monocolumn flask followed by 0.285 g (0.00129 mol) of RAFT agent (2-cyano- 2-propyl benzodithioate), 0.340 g (0.0013 1 mol) of 1,6-hexanediol dimethacrylate crosslinking agent and 16.3 g (15.8 ml) of 1,4-dioxane are added. The monomer concentration is set at 1.0 mol L ¹ . The flask is then degassed for 30 minutes under nitrogen and with magnetic stirring, then sealed. In parallel, 0.0270g (1, 61. 10 ⁴ mol) of AIBN are introduced into a second flask of 25mL and 2.0g (l, 94mL) of l, 4-dioxane as solvent dissolution. The second balloon is at his turn degassing 30 minutes under nitrogen. The AIBN solution is then transferred using a nitrogen purged syringe into the 50 mL flask, preheated to 80 ° C, to initiate polymerization. The reaction is left 24h. After the polymerization is complete, the solvent is evaporated under reduced pressure (55mbar) at 60 ° C to recover the crosslinked polymer.

Crosslinked C 1 2 / C 1 4 - 1 -vinylimidazole alkyl acrylate copolymer

(according to the invention):

10.9 g (0.044 mol) of C1 2 / C1 4 alkyl acrylate monomer and 1.03 g

(0.0109 mol) of a second A-vinylimidazole monomer are introduced into a 50 mL single-neck flask, then 0.548 g (0.00263 mol) of RAFT (2-cyano-2-propyl dodecyltrithiocarbonate) agent, 0.589 g

(0.00275 mol) of crosslinking agent and 19.8 g (19.2 ml) of 1,4-dioxane are added. The total concentration of two monomers is set at 1.5 mol L ¹ . The flask is then degassed for 30 minutes under nitrogen and with magnetic stirring, then sealed. In parallel, 0.05 g (3, 1. 10 ⁴ mol) of AIBN are introduced into a second flask of 25mL and 2.0g (l, 94mL) of l, 4-dioxane as solvent dissolution. The second flask is in turn degassed for 30 minutes under nitrogen. The AIBN solution is then transferred using a nitrogen purged syringe into the 50 mL flask, preheated to 80 ° C, to initiate polymerization. The reaction is left 24h. After polymerization is complete, the solvent is evaporated under reduced pressure (55mbar) at 60 ° C to recover the crosslinked copolymer.

A non crosslinked (comparative) C1 2 / C1 4 alkyl acrylate homopolymer, as well as additional crosslinked C1 2 / C1 4 alkyl acrylate homopolymers (in accordance with the invention) and C1 alkyl acrylate copolymers Additional 2 / C1 4 - 1 -vinylimidazole crosslinked (in accordance with the invention) were synthesized following synthetic protocols analogous to those described above. The characteristics of all the synthesized polymers are summarized in the table below:

Example 2: Evaluation of cold-holding performance

The polymers described in Example 1 were tested as cold-holding additives in a composition G diesel fuel type particularly difficult to treat, and whose characteristics are detailed in the table below:

The gas oil composition G was added with a package containing the following two commercial cold flow-forming additives (CFI additives) in solvent Solvesso 150:

- 0.5% by weight of additive CP7956C marketed by the company Total Additives Special Fuels, and which is an ethylene-vinyl acetate copolymer (EVA);

- 0.5% by weight of additive Dodiflow D4134 marketed by Clariant, and which is an ethylene-vinyl acetate-vinyl neodecanoate terpolymer.

This package was incorporated into the composition of diesel G at a content of 300 ppm by weight of active ingredient (ie 150 ppm by weight of each additive) relative to the total weight of the gas oil composition.

There was thus obtained the additive gas oil composition G l.

The performance as cold endurance additives of each of the polymers of Example 1 were tested, by evaluating their ability to lower the filterability limit temperature (TFL) of the additive gasol composition G l.

Each polymer was added at a content of 3 ppm by weight to the composition G 1, to give the G 2 gas oil, which was then measured TLF, according to the standard EN 1 16.

The results obtained are shown in the table below: The above results show that the use of the crosslinked polymers according to the invention leads to a substantial lowering of the TLF, ranging from 3 to 5 points. Surprisingly, cross-linked polymers give better results than non-crosslinked polymers.

Claims

1. Use, for lowering the filterability limit temperature, measured according to standard NF EN 1 16, of a fuel or fuel composition, of one or more crosslinked polymers comprising at least one unit of formula (I) below:

in which

R 1 represents a hydrogen atom or a methyl group,

E represents -O-CO-, or -CO-O- or -NH-CO- or -CO-NH-,

G represents a C1-C34 alkyl group,

2. Use according to claim 1, characterized in that the group E of the formula (I) is chosen from: -O-CO- and -NH-CO-, it being understood that the group E = -O-CO- is connected to the vinyl carbon by the oxygen atom and that the group E = -NH-CO- is connected to the vinyl carbon by the nitrogen atom, and preferably the group E of the formula (I) is the group -O-CO-.

3. Use according to claim 1, characterized in that the group E of the formula (I) is chosen from: -CO-O- and -CO-NH-, it being understood that the group E is connected to the vinyl carbon by the carbon atom, and preferably the group E of the formula (I) is the group -CO-O-.

4. Use according to any one of the preceding claims, characterized in that the group G of formula (I) is an acyclic straight or branched alkyl to C _34, preferably C ₄ -C _34, more preferably C ₄ to C ₃₀ , more preferably C ₆ to C ₂₄ , still more preferably C ₈ to C ₂₂ , more preferably C ₁₂ to C _{14 or} C ₁ to C ₂₂ , and more preferably still C ₁₂ to C ₁₄ .

5. Use according to the preceding claim, characterized in that the group E is a group -CO-O-, E being connected to the vinyl carbon by the carbon atom, and the group G is a linear or branched acyclic alkyl radical. Ci -C _34, preferably C ₄ -C _30, more preferably C ₆ -C _24, more preferably Cs to C _22, more preferably C ₁₂ to C ₁₄ or below s to C ₂₂ and more preferably still C ₁₂ to C _14.

6. Use according to any one of the preceding claims, characterized in that the crosslinked polymer is a homopolymer.

7. Use according to any one of claims 1 to 5, characterized in that the crosslinked polymer is a copolymer selected from block copolymers and random copolymers, preferably from random copolymers.

8. Use according to the preceding claim, characterized in that the polymer comprises at least two different units of formula (I) and / or additional units different from the units of formula (I).

9. Use according to the preceding claim, characterized in that the polymer comprises additional units different from the units of formula (I), preferably units derived from one or more vinyl monomers bearing a polar substituent.

10. Use according to the preceding claim, characterized in that the polymer comprises units derived from one or more vinyl monomers chosen from:

2-phenoxyethylacrylate:

1 -vinylimidazole: N-vinylpyrrolidone:

1 1. Use according to any one of claims 7 to 10, characterized in that the copolymer contains at least 50 mol% of units of formula (I), preferably at least 70 mol%.

12. Use according to any one of the preceding claims, characterized in that the polymer has a degree of crosslinking in the range of 1% to 20%, more preferably 2% to 10%, and more preferably 3% at 6%.

13. Use according to any one of the preceding claims, characterized in that the crosslinking agent of the polymer is chosen from di-vinyl compounds, and preferably from diacrylates and dimethacrylates of formula (III) below:

with

R representing a hydrocarbon chain comprising from 2 to 16 and preferably from 3 to 12 carbon atoms, which can be interrupted by one or more heteroatoms selected from N and O, and which may be substituted with one or more -OZ groups with Z representing a hydrogen atom or a C ₁ -C ₄ alkyl radical, and

- R ₂ and R ₃ representing, independently of one another, a hydrogen atom or a methyl group.

14. Use according to the preceding claim, characterized in that the crosslinking agent is chosen from

- 1,6 hexanediol dimethacrylate;

di (ethylene glycol) dimethacrylate;

glycerol dimethacrylate;

- 1,6 hexanediol diacrylate;

di (ethylene glycol) diacrylate, and

- 1,6 hexanediol ethoxylate diacrylate.

15. Use according to any one of the preceding claims, characterized in that the fuel or fuel composition is selected from gas oils, biodiesel, gasolines type B _s and fuel oils such as domestic fuel oils (FOD).

16. Use according to any one of the preceding claims, characterized in that said crosslinked polymer is used in combination with at least one cold-cooling additive selected from copolymers and terpolymers of ethylene and vinyl ester (s) (s). and / or acrylic (s), alone or in admixture, preferably from ethylene / vinyl acetate copolymers (EVA), ethylene / vinyl propionate (EVP), ethylene / vinyl ethanoate (EVE), ethylene / methacrylate methyl (EMMA); and more preferably from ethylene / vinyl acetate (EVA) and ethylene / vinyl propionate (EVP) copolymers; more preferably still among the ethylene / vinyl acetate copolymers (EVA).

17. Use according to any one of the preceding claims, characterized in that said crosslinked polymer is employed in a content ranging from 2 to 100 ppm by weight, still more preferably from 3 to 50 ppm by weight, and more preferably from 3 to 10 ppm by weight, based on the total weight of the composition of fuel or fuel.

18. Additive composition comprising a crosslinked polymer as defined in any one of Claims 1 to 14, and one or more cold-cooling additive (s) chosen from ethylene copolymers and terpolymers. and vinyl ester (s) and / or acrylic (s); preferably from ethylene / vinyl acetate copolymers (EVA), ethylene / vinyl propionate (EVP), ethylene / vinyl ethanoate (EVE), ethylene / methyl methacrylate (EMMA); and more preferably from ethylene / vinyl acetate (EVA) and ethylene / vinyl propionate (EVP) copolymers; more preferably still among the ethylene / vinyl acetate copolymers (EVA).

19. Additive composition according to claim 18, characterized in that it comprises from 0.3 to 30% by weight of crosslinked polymer, relative to the total weight of the additive composition.

20. Additive concentrate comprising an additive composition as defined in one of claims 18 and 19, in admixture with an organic liquid.

21. Fuel or fuel composition, comprising:

(2) at least one crosslinked polymer as defined in any one of claims 1 to 14, and

22. Composition according to the preceding claim, characterized in that it contains the crosslinked polymer (s) in a content of at least 2 ppm by weight, preferably at least 3 ppm by weight, and more preferably at least 5 ppm by weight.

23. Composition according to one of claims 21 and 22, characterized in that it contains the crosslinked polymer (s) in a content ranging from 2 to 100 ppm by weight, still more preferably from 3 to 50 ppm by weight, and more preferably from 3 to 10 ppm by weight. weight.

24. Composition according to one of claims 21 to 23, characterized in that the additive (s) fluidifying (s) cold (s) is (are) selected from ethylene / vinyl acetate copolymers (EVA), ethylene / vinyl propionate (EVP), ethylene / vinyl ethanoate (EVE), ethylene / methyl methacrylate (EMMA); and more preferably from ethylene / vinyl acetate (EVA) and ethylene / vinyl propionate (EVP) copolymers; more preferably still among the ethylene / vinyl acetate copolymers (EVA).

25. Composition according to one of claims 21 to 24, characterized in that it contains at least 20 ppm by weight, preferably at least 50 ppm by weight, preferably between 20 and 5000 ppm by weight, more preferably between 50 and 1000 ppm by weight of cold-flow additive (s).

A process for lowering the filterability limit temperature of a fuel or fuel composition comprising a step of treating said composition with at least one crosslinked polymer as defined in any one of claims 1 to 14, and with one or a plurality of coolant additive (s) chosen from copolymers and terpolymers of ethylene and of vinyl ester (s) and / or acrylic (s).