BRPI0710303A2 - engine fuel composition comprising raw materials - Google Patents

Abstract

<B> ENGINE FUEL COMPOSITIONS UNDERSTANDING RAW MATERIALS. <D> The present invention relates to engine fuel compositions comprising at least one diesel fuel of mineral origin and at least one biodiesel fuel, characterized by the fact that the The composition contains at least 20% by weight of diesel fuel of mineral origin and 0.05% to 5% by weight of at least one polymer comprising ester groups and containing repeating units that are derived from ester monomers having 7 to 15 carbon atoms in the alcohol radical. The present invention further describes the use of polymers comprising ester groups as flow intensifiers, and also a process for operating an ardiesel engine.

Description

Report of the Invention Patent for "ENGINE FUEL COMPOSITIONS UNDERSTANDING RAW MATERIALS".

The present invention relates to fuel compositions comprising renewable raw materials for the use of polymers comprising ester in fuel compositions, and the processes for operating fuel composition machines of the present invention.

Today, fuels are usually obtained from fossil sources. However, these features are limited, so replacements are being sought. In this way, interest in renewable raw materials that can be used to produce fuels is emerging. A very interesting substitution is in particular biodiesel fuels.

The term biodiesel is in many cases understood to mean a mixture of fatty acid esters, usually methyl fatty acid esters (FAMEs), with fatty acid fraction chain lengths of 14 to 24 carbon atoms of 0 to 3 double bonds. The higher the number of carbons and the fewer double bonds are present, the higher the melting point of FAME. Typical raw materials are vegetable oils (ie glycerides) such as rapeseed oils, sunflower seeds, soybean oils, palm oils, coconut oils and, in isolated cases, even used vegetable oils. These are converted to the corresponding FAMEs by transesterification, usually with methanol under base catalysis.

Unlike rapeseed oil methyl ester (RME), which is often used in Europe and typically contains approximately 5% C16: 0 + C18: 0-FAME, palm oil methyl ester (PME) contains approximately 50% of C16: 0 + C18.0-FAME. A similar C16: 0 + C18: 0 content of FAME is also possessed by the analogous derivatives of animal tallow, for example beef tallow. Such ceraalt content can hardly be influenced by polymeric flow enhancers, which are typically added with an addition rate of up to 2%. Compared to rapeseed oil, palm oil can be obtained at more than three times the height of a crop yield per hectare. This gives rise to immense economic advantages. However, a disadvantage is the high pour point of PME1 which is about + 12 ° C.

The use of pure biodiesel is an important goal from an ecological point of view. However, these fuel oils differ from conventional diesel fuel in important properties. For example, many sealing materials have been found to be attacked by biodiesel. Failure of sealing materials inevitably leads to machine damage. In addition, in the case of direct injection diesel engines, fuel can penetrate engine oil, which, due to the low chemical stability of vegetable oil esters, can create deposits in the engine. In addition, biodiesel fuels exhibit different combustion due to differences in viscosity compared to mineral diesel fuels, which create different atomization behavior. In the case of modern diesel engines, whose electronic engines are specifically tuned for fossil diesel fuel, problems may therefore arise as a result of altered combustion characteristics. In particular, the development of high performance and economical diesel engines that are optimized for the use of fossil fuels has thus far hindered the use of pure biodiesel fuel.

In addition to the use of 100% biodiesel (usually RME) in Europe, fossil diesel blends, ie the average distillate from crude oil distillation, and biodiesel are therefore also of interest due to the improved low temperature properties and better combustion properties. . Still as a blend, the tax advantages for renewable raw materials can be passed on to the end user. In addition to these economic advantages, the advantageous ecological balance for renewable feedstock biodiesel should of course also be mentioned. For example, 5% of biodiesel blends (usually RME) with fossil diesel are being discussed in Europe and Asia (South Gorea, India, Indonesia, Malaysia, Thailand, Philippines) and Australia up to 20% or higher blends (usually SMEs). ). In the case of the 20% SME blend, moreover, significantly more wax-like chains are present with approximately 10% C16: 0 + C18: 0-FAME in the fuel mixture than in the RME (approximately 5%). There is also a broad review of this subject in H. Vogel, A. Bertola: Palmolmethylester - eine neue vorteilhafteBiokomoponente für Dieselkraftstoffe [Palm Oil Methyl Ester - A New Advan-tageous Biological Component for Diesel Fuels] Mineralõltechnik 50 (2005), I.

PA (M) As polyalkyl (meth) acrylates as flow point enhancers for mineral oils, without M (M) A (e.g. US 3,869,396 for Shell Oil Company) and with M (M) A (e.g. US 5 312884 for Rohm & Haas Company), or more as flow point enhancers for vegetable oils (US 5,696,066 for Rohm & Haas Com-pany), have been established and described for some time. The use of these polymers in fuel compositions comprising at least one mineral diesel fuel and at least one biodiesel fuel, however, is not described.

In addition, WO 01/40334 (RohMax AdditivesGmbH) describes polyalkyl (meth) acrylates that can be used in biodiesel fuels. This publication relates to the particular preparation which confers exceptional properties of such polymers. However, there is a lack of examples here that refer to biodiesel fuels. In addition, the advantage of polymers having a high content of certain ester comprising repeat units is not detailed. Furthermore, the low temperature properties achieved in the oil lubricant through the addition of additives are not necessarily applicable to mineral diesel fuels, since their boiling behavior, viscosity and consequently their hydrocarbon composition is different. Mixtures comprising mineral diesel fuel and biodiesel are not described in WO 01/40334. In addition, hydroxy-functional PAMAs are known as biodiesel flow enhancers in the literature (EP 1 032 620 for RohMax Additives GmbH). In the general publication of EP 1 032 620, blends of fossil fuels with biodiesel fuels are described, but no examples using such a mixture are cited. In this context, it can be concluded from the document that a biodiesel fuel, especially based on RME, which has particularly good low temperature properties should be provided. In the case of using mixtures with a high diesel fuel content of origin mineral, it has been found that the effectiveness of the polymers, detailed in EP 1 032 620, can be improved.

Oil soluble polymer based flux enhancers for diesel and fossil biodiesel blends are also known (WO94 / 10267, Exxon Chemical Patents Inc.). However, in the examples only ethylene vinyl acetate (EVA) polymers and copolymers, which contain C12 / C14 alkyl fumarate and vinyl acetate immunities, are described. There is no complete and doubtful description of particular polymers comprising ester in WO 94/10267.

In addition, a series of EVA copolymers for biodiesel-biodiesel blends has become known (EP 1 541 662 to 664). For example, EP 1 541 663 details the blends comprising 75% by volume of diesel fuel of mineral origin and 25% by volume of biodiesel, which comprise 150 ppm poly (dodecyl methacrylate) and from 100 to 200 ppm ethylene vinyl acetate (EVA) copolymer. However, the use of EVA is described here below as mandatory. EVA is, however, a somewhat expensive additive. Consequently, alternatives with which daring of EVA can be dispensed with are desirable. There is no indication in EP 1 541 663 regarding the advantages of the particular ester comprising polymers.

In view of the prior art, it is therefore an object of the present invention to provide combustible compositions which, with a property profile corresponding essentially to that of mineral diesel fuel, comprise a maximum proportion of renewable raw materials. At the same time, the fuel must in particular have very low low temperature properties. In addition, the combustion behavior, especially the fuel behavior with respect to engine control characteristics, should as far as possible correspond to the behavior of mineral diesel fuel. Furthermore, it was an object of the present invention to provide a fuel that has a high oxidation stability. In addition, the fuel must have a maximum cetane number. At the same time, new fuels should be simple and inexpensive to produce. In addition, it was an object of the present invention to provide processes for operating diesel engines that have high environmental compatibility.

This objective and other objectives that are not explicitly determined but are immediately derivable or discernible from the connections discussed hereinafter by way of introduction are achievable by a combustible composition having all the characteristics of claim 1. Appropriate modifications of the The fuel composition of the invention are protected in subclaims. With respect to the process for operating a diesel engine and the use of polymers comprising ester as Flow Enhancers, claims 24 and 25 constitute a solution to the problem.

By virtue of a fuel composition containing 20% by weight of diesel fuel of mineral origin and from 0.05 to 5% by weight of at least one ester-comprising polymer comprising repeating units which are derived from ester monomers must be 16 to 40 carbon atoms in the alcohol radical, and repeat units that are derived from ester monomers having 7 to 15 carbon atoms in the alcohol radical, it is surprisingly possible to provide a combustible composition comprising at least a mineral diesel fuel and at least one biodiesel fuel, which, with a property profile that is very similar to that of mineral diesel fuel, comprises a very high proportion of renewable raw materials.

At the same time, the combustible compositions of the invention can achieve a number of additional advantages. These include: The combustible compositions of the invention may be used in conventional diesel engines without the commonly used sealing materials being attacked.

In addition, modern diesel engines can be operated with the fuel of the present invention without engine control having to be changed.

Preferred fuel compositions of the present invention have a particularly high cetane number which can be particularly improved by the use of biodiesel fuels having a high proportion of long chain saturated fatty acids.

In addition, the present invention is directed to the use of very oxidation stable biodiesel fuels. This allows for reduced engine deformation deposits, which can lead to overall low engine performance.

In addition, very high fractions of calming oil alkyl esters may be used in fuels. For ecological and eco-nomic reasons, palm oil is preferred over commonly used rapeseed oil. For example, the yield of the crop in the production of calming oil is significantly higher than that of rapeseed oil. In addition, to obtain rapeseed, very large quantities of ecologically controversial chemicals, especially fertilizers and crop protection compositions, are used. At the same time, rapeseed is not self-compatible in production and must be grown in a rotary harvesting system, in which case rapeseed cultivation in the same field is only possible every 3 to 5 years. For this reason, an additional increase in rapeseed production is difficult.

However, palm oil alkyl esters have a significantly higher turbidity point (approx. + 13 ° C for demethyl ester) compared to rapeseed oil alkyl esters; The melting point of the rapeseed alkyl alkyl ester is significantly lower (at-approx. -7 ° C for methyl ester). In a particular aspect, the present invention thus allows the use of particularly high proportions of palm oil alkyl esters for the production of combustible compositions without the low temperature properties assuming non-permissible values.

The fuel composition of the present invention comprises diesel fuel of mineral origin, ie diesel, gasoline or die-sel oil. Diesel fuel is widely known per se and is commercially available. This means a mixture of different hydrocarbons that is suitable as a fuel for a diesel engine. Dieselp can be obtained as a medium distillate, in particular by distillation of a crude oil. The major constituents of diesel fuel preferably include alkanes, cycloalkanes and aromatic hydrocarbons having about 10 to 22 carbon atoms per molecule.

Preferred diesel fuels of mineral origin boil in the range of 120 to 450 ° C, more preferably 170 and 390 ° C. Preference is given to the use of those middle distillates containing 0.05 wt% sulfur and less, more preferably less than 350 ppm sulfur, in particular less than 200 ppm sulfur and in special cases less than 50 ppm sulfur. sulfur, for example less than 10 ppm sulfur. They are preferably those middle distillates that have been refined under hydrogenation conditions, and which therefore contain only small proportions of polar polyaromatic compounds. They are preferably those medium distillates having 95% distillation points below 370 ° C, in particular below 350 ° C and in special cases below 330 ° C. Synthetic fuels, when obtainable, for example, by the Fischer-Tropsch process, are also suitable as diesel fuels of mineral origin.

The kinematic viscosity of the diesel fuels of mineral origin to be used is preferably in the range 0.5 to 8 mm2 / s, more preferably 1 to 5 mm2 / s and preferably 1.5 to 3 mm2 / s, measured at 40 °. C for ASTM D 445.

The combustible compositions of the present invention comprise at least 20 wt%, in particular at least 30 wt%, preferably at least 50 wt%, more preferably at least 70 wt%, and more preferably at least 80 wt%. diesel fuels of mineral origin.

In addition, the present fuel composition comprises at least one biodiesel fuel component. Biododiesel fuel is a substance, especially an oil, which is obtained from plant or animal material or both, or a derivative thereof which can in principle be used as a replacement for mineral diesel fuel.

In a preferred embodiment, biodiesel fuel, which is often also referred to as "biodiesel" or "biofuel" comprises fatty acid alkyl esters formed from fatty acids preferably having from 6 to 30, more preferably 12. to 24 carbon atoms; and monohydric alcohols having from 1 to 4 carbon atoms. In many cases, some of the fatty acids may contain one, two or three double bonds. Monohydric alcohols include in particular methanol, ethanol, propanol and butanol, methanol being preferred.

Examples of oils derived from plant or animal material which may be used according to the invention are palm oil, rapeseed oil, coriander oil, soybean oil, cottonseed oil, sunflower oil, castor oil, oil. olive oil, ground almond oil, corn oil, almond oil, palm kernel oil, coconut oil, mustard seed oil, oils that are derived from animal tallow, especially beef tallow, bone oil, used fish and cooking oils. In addition, examples include oils derived from cereal, wheat, jute, sesame, dried rice husks, jatropha, arachis oil and flaxseed oil. The fatty acid alkyl esters to be used may preferably be obtained from these oils by the methods known in the prior art.

Preference is given according to the invention to oils containing high C16: 0 / C18: 0-glyceride content, such as palm oils and oils which are derived from animal tallow, and also derivatives thereof, especially esters. palm oil alkyl compounds which are monohydric dealcool derivatives. Palm oil (also: palm fat) is obtained from the fruit pulp of palm fruits. The fruits are sterilized and pressed. Due to their high carotene content, fruits and oils have a red-orange color that is removed in refinement. The oil may contain up to 80% C18: 0-glyceride.

Particularly suitable are fatty acid lower alkyl esters. Examples useful herein are the commercial mixtures of ethyl, propyl, butyl and especially methyl esters of fatty acids having from 6 to 30, preferably 12 to 24, more preferably 14 to 22 carbon atoms, for example caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, margaric acid, stearic acid, arachic acid, behenic acid, lignoceric acid, cerotic acid, palmitoleic acid, stearic acid, oleic acid, elastic acid, petroselic acid, ricinoleic acid, elasostearic acid, linoleic acid, linolenic acid, eicosanoic acid, acidic acid, docosanoic acid or eruric acid.

In a particular aspect of the present invention, a biodiesel fuel is used which preferably comprises at least 30 wt.%, More preferably at least 35 wt.% And more preferably at least 40 wt.% Of saturated fatty acid esters. have at least 16 carbon atoms in the fatty acid radial. These include in particular palmitic acid and stearic acid esters.

For cost reasons, these fatty acid esters are generally used with a mixture. Usable biodiesel fuels according to the invention preferably have an iodine number of at most 150, in particular at most 125, more preferably at most 70 and more preferably at most 60. The iodine number is a measure known per se for contains a fat or oil of unsaturated compounds which may be determined to DIN 53241-1. As a result of this, the fuel compositions of the present invention form a particularly low level of deposits in diese engines. Moreover, these combustible compositions have particularly high cetane numbers.

In general, the fuel compositions of the present invention may comprise at least 0.5 wt.%, In particular at least 3 wt.%, Preferably at least 5 wt.% And more preferably at least 15 wt.% Biodiesel fuel.

Furthermore, the fuel composition of the present invention comprises 0.05 to 5 wt.%, Preferably 0.08 to 3 wt.% And more preferably 0.1 to 1.0 wt.% Of at least one polymer comprising ester.

In the present context, the polymers comprising ester are understood to mean polymers which are obtainable by polymerization of the monomer compositions which comprise the ethylenically unsaturated compounds having at least one ester group, which is referred to hereafter as ester monomers. Consequently, these polymers contain ester groups as part of the side chain. These polymers include in particular alkyl poly (meth) acrylates (PAMAs), dealkyl polyfumarates and / or alkyl polymathides.

Ester monomers are known per se. These include in particular (meth) acrylates, maleates and fumarates which may have different alcohol radicals. The term (meth) acrylates includes methacrylates and acrylates, as well as mixtures of the two. These monomers are widely known. In this context, the alkyl radical may be linear, cyclic or branched. In addition, the alkyl radical may have known substituents.

Ester comprising polymers contain repeating units which are derived from ester monomers having 16 to 40 carbon atoms in the alcohol radical, and repeating units which are derived from ester monomers having 7 to 15 carbon atoms in the radical alcohol.

The term "repetition unit" is widely known in the technical field. The present ester-comprising polymers may preferably be obtained by monomer free radical polymerization, the processes ATRP, RAFT and NMP1 which will be detailed below, being included in the free radical processes in the context of the invention; without any intention of imposing a restriction. In polymerization, double bonds are opened to form covalent bonds. Consequently, the repeating unit is formed from the monomers used.

The polymer comprising ester may contain 5 to 99.9 wt%, in particular 20 to 98 wt%, preferably 30 to 95 wt% and more preferably 70 to 92 wt% of repeat units which are derived from ester monomers which have to be 7 to 15 carbon radical atoms alcohol.

In a particular aspect, the ester-comprising polymer may contain 0.1 to 80 wt%, preferably 0.5 to 60 wt%, more preferably 2 to 50 wt% and more preferably 5 to 20 wt% repeating units. which are derived from ester monomers having from 16 to 40 carbon atoms in the alcohol radical.

In addition, the ester-comprising polymer may contain from 0.1 to 30% by weight, preferably 0.5 to 20% by weight, of repeating units which are derived from ester monomers having from 1 to 6 carbon atoms. in the alcohol radical.

The ester comprising polymer preferably comprises at least 40 wt%, more preferably at least 60 wt%, especially and preferably at least 80 wt% and more preferably at least 95 wt% of repeat units which are derived from ester monomers.

Mixtures from which the polymers comprising ester of the invention are obtainable may contain from 0 to 40% by weight, preferably from 0.1 to 30% by weight, in particular from 0.5 to 20% by weight, of one or more compounds of the invention. ethylenically unsaturated ester of formula (I)

<formula> formula see original document page 12 </formula>

wherein R is hydrogen or methyl, R1 is a straight or branched alkyl radical having from 1 to 6 carbon atoms, R2 and R3 are each independently hydrogen or a group of the formula -COOR 'where R' is hydrogen or a alkyl group having from 1 to 6 carbon atoms. Examples of Component (I) include:

(meth) acrylates, fumarates and maleates which are derived from saturated alcohols such as methyl (meth) acrylate, demethyl (meth) acrylate, n-propyl methacrylate, (isopropyl methacrylate), (meth) den-butyl acrylate, tert-butyl (meth) acrylate and pentyl (meth) acrylate, hexyl (meth) acrylate;

cycloalkyl (meth) acrylates such as cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate;

(meth) aerylates which are derived from unsaturated alcohols, such as 2-propynyl (meth) acrylate, allyl (meth) acrylate and vinyl (meth) acrylate.

The compositions to be polymerized preferably contain from 10 to 98% by weight, in particular from 20 to 95% by weight, of one or more ethylenically unsaturated ester compounds of formula (II).

<formula> formula see original document page 13 </formula>

where R is hydrogen or methyl, R4 is a straight or branched alkyl radical having from 7 to 15 carbon atoms, R5 and R6 are each independently hydrogen or a group of the formula -COOR "where R" is hydrogen or a alkyl group having from 7 to 15 carbon atoms. Examples of Component (II) include:

(meth) acrylates, fumarates and maleates which are derived from saturated alcohols, such as 2-ethylhexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, methyl acrylate , 3-isopropylheptyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth) acrylate, 5-methylundecyl (meth) acrylate, (meth) acrylate 2-methyldodecyl, tridecyl (meth) acrylate, 5-methyltridecyl (meth) acrylate, tetradecyl (meth) acrylate, pen-tadecyl (meth) acrylate, which are derived from unsaturated alcohols, for example, oleyl (meth) acrylate;

cycloalkyl (meth) acrylates such as 3-vinylcyclohexyl (meth) acrylate, butyl (meth) acrylate; and the corresponding fumarates and maleates.

In addition, the preferred monomer compositions contain from 0.1 to 80% by weight, preferably from 0.5 to 60% by weight, more preferably from 2 to 50% by weight and more preferably from 5 to 20% by weight of one or more. more ethylenically unsaturated ester compounds of formula (III)

<formula> formula see original document page 14 </formula>

wherein R is hydrogen or methyl, R 7 is a straight or branched alkyl radical which has from 16 to 40, preferably from 16 to 30, carbon atoms R 8 and R 9 are each independently hydrogen or a group of the formula -COOR "'where R 1 "is hydrogen or an alkyl group having from 16 to 40, preferably from 16 to 30, carbon atoms.

Examples of Component (III) include (meth) acrylates which derive from saturated alcohols such as hexadecyl (meth) acrylate, 2-methylhexadecyl (meth) acrylate, heptadecyl (meth) acrylate, 5-isopropylheptadecyl (4-tert-butyloctadecyl (meth) acrylate, 5-ethyloctadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate, (meth) eicosyl acrylate, (meth) cetileicosyl acrylate, (meth) stearylethylsyl acrylate, (meth) acrylate of docosyl and / or (meth) eicosyl tetratriacontyle;

cycloalkyl (meth) acrylates such as 2,4,5-tri-t-butyl-3-vinylcyclohexyl (meth) acrylate; 2,3,4,5-tetra-t -butylcyclohexyl (meth) acrylate; and the corresponding fumarates and maleates.

Ester compounds which have a long chain alcohol radical, especially components (II) and (III), can be obtained, for example, by reaction of (meth) acrylates, fumarates, maleates and / or acids corresponding to long chain fatty alcohols, which generally gives a mixture of esters, for example (meth) acrylates with various long chain radicals. These fatty alcohols include Oxo Alcohol®7911 and Oxo Alcohol® 7900, Oxo Alcohol® 1100 types; Alfol® 610, Alfol® 810, Li-ai® 125 and Nafol® (Sasol); Alphanol® 79 (ICI); Epal® 610 and Epal® 810 (Af-ton); Linevol® 79, Linevol® 911 and Neodol® 25E (Shell AG); Dehidad®, Hidrenol® and Lorol® (Cognis) types; Acropol® 35 and Exxal® 10 (Exxon Chemicals); Kalcol 2465 (Kao Chemicals).

Of the ethylenically unsaturated ester compounds, particular preference is given to (meth) acrylates over maleates and fumarates, that is, R2, R3, R5, R6, R8 and R9 of formulas (I), (II) and ( III) are each hydrogen in particularly preferred embodiments.

The weight ratio of ester monomers of formula (II) to ester monomers of formula (III) may be within a broad range. The ratio of the ester compounds of formula (II) which contain from 7 to 15 carbon atoms in the alcohol radical to the ester compounds of formula (III) which contain from 16 to 40 carbon atoms in the alcohol radical is preferably in the range of 50: 1 to 1:30, more preferably in the range of 10: 1 to 1: 3, especially and preferably 5: 1 to 1: 1.

Component (IV) comprises in particular ethylenically unsaturated monomers which may be copolymerized with the ethylenically unsaturated ester compounds of formulas (I), (II) and / or (III).

However, comonomers particularly suitable for polymerization according to the present invention are those corresponding to the formula:

<formula> formula see original document page 15 </formula>

wherein R1 * and R2 * are each independently selected from the group consisting of hydrogen, halogens, CN, linear or branched alkyl groups having from 1 to 20, preferably from 1 to 6 and more preferably from 1 to 4, carbon atoms which may be substituted by 1a (2n + 1) halogen atoms, where η is the number of carbon atoms in the alkyl group (eg CF3), α, β-unsaturated linear or alkenyl groups which have from 2 to 10, preferably 2 to 6 and more preferably from 2 to 4, carbon atoms which may be substituted by 1 to (2n-1) halogen atoms, preferably chlorine, where η is the number of carbon atoms of alkyl group, for example CH2 = CCl-, cycloalkyl groups having from 3 to 8 carbon atoms which may be substituted by 1 to (2n-1) halogen atoms, preferably chlorine, whereη is the number of carbon atoms of the cycloalkyl group; C (= I *) R5 *, C (= I *) NR6 * R7 *, IC (= I *) R5 *, SOR5 *, SO2R5 *, OSO2R5 *, NR8 * SO2R5 *, PR5 * 2, P (= I *) R5 * 2,1 * PR5 * 2,1 * P (= r) R5 * 2, NR8 * 2 which may be quaternized with an additional R8 *, aryl or heterocyclyl group, where I * may be NR8 *, S or O, preferably O; R5 * is an alkyl group having from 1 to 20 carbon atoms, an alkylthio having from 1 to 20 carbon atoms, OR15 (R15 is hydrogen or an alkali metal), alkyloxy of 1 to 20 carbon atoms, aryl hydroxy or heterocyclyloxy; R 6 * and R 7 * are each independently hydrogen or an alkyl group having from 1 to 20 carbon atoms, or R 6 * and R 7 * together may form an alkylene group having from 2 to 7, preferably from 2 to 5 carbon atoms. carbon, in which case they form a 3- to 8-membered ring, preferably 3- to 6-membered ring, and R8 * is hydrogen, straight or branched alkyl or aryl groups having from 1 to 20 carbon atoms; R3 * and R4 * are independently selected from the group consisting of hydrogen, halogen (preferably fluorine or chlorine), alkyl groups having from 1 to 6 carbon atoms and COOR9 * wherein R9 * is hydrogen, an alkali metal or an alkyl group having from 1 to 40 carbon atoms, or R 3 * and R 4 * together may form a group of the formula (CH 2) n 'which may be substituted by 1 to 2 n' halogen atoms or C 1 to C 4 alkyl groups, or form the formula C (= 0) -C (= 0) where n 'is 2 to 6, preferably 3 or 4, and Γ is as defined above; and where at least 2 teeth the radicals R1 *, R2 *, R3 * and R4 * are hydrogen or halogen.

Preferred comonomers (IV) include hydroxyalkyl (meth) acrylates such as 3-hydroxypropyl methacrylate, 3,4-dihydroxybutyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 5-dimethyl-1,6-hexanediol, 1,10-decanediol (meth) acrylate; aminoalkyl (meth) acrylates such as N- (3-dimethylaminopropyl) methacrylamide, 3-diethylaminopentyl methacrylate, 3-dibutylaminohexadecyl (meth) acrylate; (meth) acrylic acid nitriles and other nitrogen-containing methacrylates, such as N- (methacryloyloxyethyl) diisobutyl ketimine, N- (methacryloyloxyethyl) dihexadecyl ketimine, methycryloylamidoacetonitrile, 2-methacryloyloxyethylmethylcyanamide, methacrylate; dearyl (meth) acrylates such as benzyl methacrylate or phenyl methacrylate wherein the aryl radicals may each be unsubstituted or even tetrasubstituted, carbonyl containing methacrylates such as 2-carboxyethyl methacrylate, carboxymethyl methacrylate, oxazolidinylethyl, N- (methacryloyloxy) formamide, acetonyl methacrylate, N-methacryloylmorpholine, N-methacryloyl-2-pyrrolidinone, N- (2-methacryloyloxyethyl) -2-pyrrolidinone, N- (3-methacryloyloxypropyl) -2-pyrrolidinone - (2-methacryloyloxypentadecyl) -2-pyrrolidinone, N- (3-methacryl-oiloxyheptadecyl) -2-pyrrolidinone; glycol dimethacrylates such as 1,4-butanediol methacrylate, 2-butoxyethyl methacrylate, 2-ethoxyethoxymethyl methacrylate, 2-ethoxyethyl methacrylate; ether alcohol methacrylates, such as tetrahydrofurfuryl methacrylate, vinyloxyethoxymethyl methacrylate, methoxyethoxyethyl methacrylate, 1-butoxypropyl methacrylate, 1-methyl- (2-vinyloxy) ethyl methacrylate, methoxymethyl methacrylate methacrylate methacrylate methacrylate benzyloxymethyl, furfuryl methacrylate, 2-butoxyethyl methacrylate, 2-ethoxyethoxymethyl methacrylate, 2-ethoxyethyl methacrylate, allyloxymethyl methacrylate, 1-ethoxybutyl methacrylate, methoxymethyl methacrylate methacrylate; halogenated alcohol methacrylates such as dibromopropyl 2,3-methacrylate, 4-bromophenyl methacrylate, 1,3-dichloro-2-propyl methacrylate, 2-bromoethyl methacrylate, 2-iodoethyl methacrylate chloromethyl methacrylate oxiranyl methacrylates such as 2,3-epoxybutyl methacrylate, 3,4-epoxybutyl methacrylate, 10,11-epoxyundecyl methacrylate, 10,11-epoxyhexadecyl methacrylate, 2,3-epoxycyclohexyl methacrylate; glycidyl methacrylate; phosphorus, boron and / or silicon containing methacrylates such as 2- (dimethylphosphate) propyl methacrylate, 2- (ethylene phosphite) propyl methacrylate, dimethylphosphinomethyl methacrylate, diethyl methacrylate diethyl methacrylate,

dipropyl methacryloyl phosphate, 2- (dibutylphosphono) ethyl methacrylate,

2,3-butylene methacrylethyl borate, methyl diethoxymethacryloyl ethoxysilane, diethylphosphateethyl methacrylate;

vinyl halides, for example vinyl chloride, vinyl fluoride, vinylidene chloride and vinylidene fluoride;

heterocyclic (meth) acrylates such as 2- (1-imidazolyl) ethyl (meth) acrylate, 2- (4-morpholinyl) ethyl (meth) acrylate and 1- (2-methacryloxyethyl) -

2-pyrrolidinone;

vinyl esters such as vinyl acetate; styrene, substituted styrene having a side chain alkyl substituent, for example α-methylstyrene and α-ethylstyrene, substituted styrene having an alkyl substituent on the ring, such as vinyl toluene and ep-methylstyrene, styrene halogenated, for example monochlorostyrenes, dichlorostyrenes, tribrostostenes and tetrabromostyrenes;

heterocyclic vinyl compounds such as 2-vinylpyridine,

3-vinylpyridine, 2-methyl-5-vinylpyridine, 3-ethyl-4-vinylpyridine, 2,3-dimethyl-5-vinylpyridine, vinylpyrimidine, vinylpiperidine, 9-vinylcarbazole, 3-vinylcarbazole,

4-Vinylcarbazole, 1-Vinylimidazole, 2-Methyl-1-Vinylimidazole, N-Vinylpyrrolidone, 2-Vinylpyrrolidone, N-Vinylpyrrolidine, 3-Vinylpyrrolidine, N-Vinylcaprolactam, N-Vinylbutyrolactam, Vinyloxuran, Vinylfuran, Vinylthioleyl, Vinylfuran hydrogenated thiazols and vinylthiazoles, vinyloxazoles and hydrogenated vinyloxazoles;

vinyl and isoprenyl ethers;

maleic acid and derivatives of maleic acid other than those mentioned under (I), (II) and (III), for example maleic anhydride, methylmaleic anhydride, maleimide, methylmaleimide;

fumaric acid and different fumaric acid derivatives from those mentioned under (I), (II) and (III).

The proportion of comonomers (IV) may vary depending on the use and the property profile of the polymer. In general, this ratio may be in the range from 0 to 60 wt%, preferably from 0.01 to 20 wt% and more preferably from 0.1 to 10 wt%. Due to combustion properties and for ecological reasons, the proportion of monomers comprising aromatic groups, heteroaromatic groups, nitrogen containing groups, phosphorus containing groups and sulfur containing groups should be minimized. The proportion of monomers may therefore be restricted to 1 wt.%, In particular 0.5 wt.% And preferably 0.01 wt.%.

Comonomers (IV) and ester monomers of formulas (I), (II) and (III) may each be used individually or as mixtures.

Surprisingly, ester-comprising polymers have better activity in mineral diesel fuel and biodiesel fuel mixtures which merely comprise a small proportion, sealguma, of units that are derived from hydroxyl-containing monomers. This is especially true of biodiesel fuels which have a high proportion of saturated fatty acids which have at least 16 carbon atoms in the acid radical. Accordingly, ester-comprising polymers to be preferably used in the fuel mixtures of the invention preferably contain at most 5 wt%, preferably at most 3 wt%, more preferably at most 1 wt% and most preferably at most 0.1 wt. % by weight of units which are derived from hydroxyl-containing monomers. These include hydroxyalkyl (meth) acrylates and vinyl alcohols. These monomers have been detailed above.

Similarly, ester-comprising polymers have better activity in mineral diesel fuel and biodiesel fuel mixtures which comprise only a small proportion, if any, of repeating units which are derived from oxygen-containing tendoradical alcohol monomers. of the formula (IV1

<formula> formula see original document page 20 </formula>

Where

R is hydrogen or methyl, R 10 is an alkyl radical which is substituted by an OH group and has 2 to 20 carbon atoms, or an alkoxy-side radical of formula (V)

<formula> formula see original document page 20 </formula>

wherein R13 and R14 are each independently hydrogen or methyl, R15 is hydrogen or an alkyl radical having 1 to 20 carbon atoms, and η is an integer from 1 to 30,

R 11 and R 12 are each independently hydrogen or a group of the formula -COOR "" where R "" is hydrogen or an alkyl radical which is substituted by an OH group and has 2 to 20 carbon atoms, or alkoxylated radical of the formula ( V)

<formula> formula see original document page 20 </formula>

wherein R13 and R14 are each independently hydrogen or methyl, R15 is hydrogen or an alkyl radical having 1 to 20 carbon atoms, and η is an integer from 1 to 30.

Ester comprising polymers to be preferably used have a TE100 thickening efficiency in the range of 4.0 to 50 mm2 / s, preferably 7.5 to 29 mm2 / s. Thickening efficiency (TE100) is determined at 100 ° C in a 150N reference oil (KV100 = 5.42mm2 / s, KV40 = 31.68 mm2 / s and Vl = 103) using 5% by weight of the polymer. Designations KV100 and KV40 describe the kinematic viscosity of the oil at 100 ° C and 40 ° C respectively for ASTM D445, the abbreviation viscosity index V1 determined for ASTM D 2270.

Ester-comprising polymers to be used according to the invention may generally have a molecular weight in the range of 1000 to 1,000,000 g / mol, preferably in the range of 25,000 to 700,000 g / mol and more preferably in the range of 40,000 to 600,000. g / mol and more preferably in the range of 60,000 to 300,000 g / mol without any intention to impose a restriction. These values are based on the weight average molecular weight Mw of the polydisperse polymers in the composition. This parameter can be determined by GPC.

Preferred copolymers, which may be obtained by polymerizing unsaturated ester compounds, preferably have a Mw / Mn polydispersion in the range of 1 to 10, more preferably 1.05 to 6.0 and more preferably 1.2 to 5.0. This parameter can be determined by GPC.

The architecture of ester-comprising polymers is not critical to many applications and properties. Accordingly, the polymers comprising ester may be random copolymers, gradient copolymers, block copolymers or graft copolymers.

Block copolymers and gradient copolymers may be obtained, for example, by altering the monomer composition discontinuously during chain growth. The blocks derived from the ester compounds of the formulas (I), (II) and / or (III) preferably have at least 30 monomer units.

The preparation of polyalkyl esters from the compositions described above is known per se. Thus, these polymers can be obtained in particular by free radical polymerization and by related processes, for example, ATRP (= Atom Transfer Radical Polymerization) or RAFT (= Reversible Mortar Fragmentation Chain Transfer).

Usual free radical polymerization is described, inter alia, in UIImann1S Encyclopedia of Industrial Chemistry, sixth edition. In general, a polymerization initiator and a chain protractor are used for this purpose. Usable initiators include widely known azo initiators such as AIBN and 1,1-azobisciclohexane carbonitrile, and also peroxy compounds such as methyl ethyl ketone peroxide, acetylacetone peroxide, dilauryl peroxide, Tert-Butyl 2-ethylhexanoate, ketone peroxide, tert-butyl peroctoate, methylisobutyl ketone peroxide, cyclohexanone peroxide, dibenzoyl peroxide, tert-butyl peroxy isopropylcarbonate, 2,5-bis (2-ethylhexanoylperoxy) -2,5-dimethylhexane, tert-butyl peroxy-2-ethylhexanoate, tert-butyl peroxy-3,5,5-trimethylhexanoate, dicumyl peroxide, 1,1-bis (tert-butylperoxy) cyclohexane, 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane, cumyl hydroperoxide, tert-butyl hydroperoxide, bis (4-tert-butylcyclohexyl) peroxydicarbonate, mixtures of two or more of the above-mentioned compounds with each other, and mixtures of the above compounds with co compounds that have not been mentioned but which may likewise form free radicals. Suitable transporters in particular are oil-soluble mercaptans, for example, dodecyl mercaptan or 2-mercaptoethanol, or other chain transfer agents from the terpene class, for example terpinols.

The ATRP process is known per se. It is assumed to be a free "living" radical polymerization, without any intention that it be restricted to the description of the mechanism. In these processes, a transition metal compound is reacted with a compound having a transferable atom group. This transfers the transferable atom group to the transition metal oxidizing demetal compound. This reaction forms a radical that adds to ethylene groups. However, the transfer of the atom group to the transition metal compound is reversible, so that the atom group is transferred back to the developing polymer chain, which forms a system of controlled polymerization. The polymer structure, molecular weight and molecular weight distribution can be controlled accordingly. This reaction is described, for example, J. S. Wang, et al., J. Am. Chem. Soc., Vol. 117, p. 5614-5615 (1995), by Matijas-zewski, Macromolecules, vol. 28, p. 7901-7910 (1995). In addition, patent applications WO 96/30421, WO 97/47661, WO 97/18247, WO 98/40415 and WO 99/10387 describe variants of the ATRP explained above.

In addition, the polymers of the invention may be obtained, for example, also by the RAFT methods. This process is set forth in detail, for example, in WO 98/01478 and WO 2004/083169, which reference is made explicitly for the purposes of the description.

In addition, the polymers of the invention are also obtainable by NMP (nitroxide-mediated polymerization) processes, which is described, inter alia, in US 4581429.

These methods are understandably described, in particular with other references, inter alia, in K. Matijazewski, T.P. Davis, Handbook of Radical Polymerization, Wiley Interscience, Hoboken 2002, to which reference is made explicitly for the purposes of the description.

Polymerization can be carried out at standard pressure, reduced pressure or high pressure. The polymerization temperature is also not critical. However, it is generally in the range of -20 ° - 200 ° C, preferably 0 ° - 130 ° C and more preferably 60 ° - 120 ° C.

Polymerization may be carried out with or without solvent. The term solvent is to be understood here in a broad sense.

The polymerization is preferably carried out in a nonpolar solvent. These include hydrocarbon solvents, for example aromatic solvents such as toluene, benzene and xylene, saturated hydrocarbons, for example cyclohexane, heptane, octane, nonane, decane, dodecane, which may also be present in branched form. These solvents may be used individually and as a mixture. Particularly preferred solvents are mineral oils, diesel fuels of mineral origin, natural animal and vegetable oils, biodiesel and oleosynthetic fuels (e.g., ester oils such as dinonyl adipate), and mixtures thereof. Of these, very particular preference is given to mineral oils and mineral diesel fuels.

The fuel composition of the invention may further comprise additives in order to achieve specific solutions to problems. These additives include dispersants, for example wax dispersants and dispersants for polar, demulsifying, defoaming agents, lubricant additives, antioxidants, cetane number enhancers, detergents, dyes, corrosion inhibitors and / or odorants.

For example, the fuel composition of the invention may comprise ethylene copolymers which are described, for example, in EP-A-1,541,663. These ethylene copolymers may contain from 8 to 21% emmol of one or more vinyl esters. and / or (meth) acrylic and 79 to 92% by weight of ethylene. Particular preference is given to ethylene copolymers containing from 10 to 18 mole% and especially from 12 to 16 mole% of at least one vinyl ester. Suitable vinyl esters are derived from fatty acids having straight or branched alkyl groups having from 1 to 30 carbon atoms. Examples include vinyl acetate, vinyl propionate, vinyl butyrate, vinyl hexanoate, vinyl heptanoate, vinyl octanoate, vinyl laurate and vinyl stearate, and also vinyl alcohol esters based on branched fatty acids, such as such as vinyl isobutyrate, vinyl pivotal, vinyl 2-ethylhexanoate, vinyl isononate, vinyl neononate, vinyl neodecanoate and vinyl neoundecanoate. Comonomers which are similarly suitable are esters of methacrylic acid acrylic acid having 1 to 20 carbon atoms in the alkyl radical, such as methyl (meth) acrylate, ethyl (meth) acrylate, (meth) acrylate N-and isobutyl (meth) acrylate, hexyl (meth) acrylate, octi-la (meth) acrylate, 2-ethylhexyl (meth) acrylate, decyl (meth) acrylate, do-decyl, (meth) tetradecyl acrylate, (meth) hexadecyl acrylate, (meth) octadecyl acrylate, and also mixtures of two, three or four or more of these comonomers.

Particularly preferred terpolymers of 2-ethylhexanoate devinyl, vinyl neononanoate and vinyl neodecanoate contain, other than ethylene, preferably 3.5 to 20 mol%, in particular 8 to 15 mol%, vinyl acetate and 0.1 to 12 mol%, in particularly 0.2 to 5 mol%, of the particular long chain vinyl ester, the total comonomer content being between 8 and 21 mol%, preferably between 12 and 18 mol%. Preferred additional copolymers contain, in addition to ethylene and 8 to 18 mol% of vinyl esters, also 0.5 to 10 mol% of olefins such as propene, butene, isobutylene, hexene, 4-methylpentene, octene, diisobutylene and / or norbornene.

The ethylene copolymers preferably have molecular weights corresponding to viscosities at 140 ° C from 20 to 10,000 mPas, in particular 30 to 5000 mPas and especially 50 to 1000 mPas. The degrees of branch determined by spectroscopy 1HNMR are preferably from 1 to 9 CH3 / 100 CH2 groups, in particular from 2 to 6 CH3 / 100 CH2 groups, for example 2.5 to 5 CH3 / 100CH2 groups, which do not originate from the comonomers.

Such ethylene copolymers are described in detail, inter alia, in DE-A-34 43 475, EP-BO 203 554, EP-BO 254 284, EP-BO 405 270, EP-BO 463 518, EP-BO 493 769. , EP-O 778 875, DE-A-196 20 118, DE-A-19620 119 and EP-AO 926 168.

Preference is given in this context to ethylene-vinyl acetate copolymers and terpolymers which in addition to ethylene and vinyl acetate repeat units also have (meth) acrylic ester repeat units. These polymers may be structured, for example, as random copolymers, as block copolymers or as graft copolymers.

In a preferred embodiment, the fuel composition of the invention may comprise from 0.0005 to 2 wt.%, Preferably from 0.01 to 0.5 wt.%, Of ethylene copolymers.

For cost reasons, however, a proportion of the ethylene copolymers described above may be dispersed within an additional embodiment, in which case these combustible compositions without a significant proportion of ethylene copolymers have surprising properties. The proportion of ethylene copolymers may preferably be at most 0.05 wt%, more preferably at most 0.001 wt% and more preferably at most 0.0001 wt%.

Preferred fuel compositions consist of 20.0 to 97.95 wt.%, In particular 70 to 94.95 wt.% Of mineral diesel fuel, 2.0 to 79.95 wt.%, In particular 5.0 to 29.95 wt.% Biodiesel fuel, 0.05 to 5% by weight, in particular 0.1 to 1% by weight, of polymer comprising ester and 0 to 60% by weight, in particular 0.1 to 10% by weight, of additives.

The combustible compositions of the invention preferably have an iodine number of at most 30, more preferably at most 20 and more preferably at most 10.

In addition, the combustible compositions of the invention have surprising low temperature properties. In particular, the pour point (PP) for ASTM D97 preferably has values of less than or equal to 0 ° C, preferably less than or equal to -5 ° C and more preferably less than or equal to -10 °. Ç. The filterability limit (cold filter closure point, CFPP) measured for DIN EN 116 is preferably a maximum of 0 ° C, more preferably a maximum of -5 ° C and more preferably a maximum of -10 ° C. . In addition, the turbidity point (CP) forASTM D2500 of preferred fuel compositions may assume values of less than or equal to 0 ° C, preferably less than or equal to -5 ° C and more preferably less than or equal to -10 ° C.

The cetane number for DIN 51773 of combustible compositions of the invention is preferably at least 50, more preferably at least 53, in particular at least 55 and more preferably at least 58.

The viscosity of the present combustible compositions may be within a wide range, and may be adjusted for intended use. This adjustment can be made, for example, by selecting biodiesel fuels or mineral diesel fuels. In addition, the hazardousness may be varied by the amount and molecular weight of the ester-comprising polymers used. The kinematic viscosity of the preferred fuel compositions of the present invention is in the range of 1 to 10 mm2 / s, more preferably 2 to 5 mm2 / s and especially preferably 2.5 to 4 mm2 / s, measured at 40 ° C at ASTM D445.

The use of ester-comprising polymers comprising repeating units derived from unsaturated esters having from 7 to 15 carbon atoms in the alcohol radical and repeating units derived from unsaturated esters having from 16 to 40 carbon atoms in the alcohol radical at a concentration of 0.05 to 5% by weight as a flow enhancer in fuel compositions comprising at least one diesel fuel of mineral origin and at least one diesel fuel, therefore, provides fuel compositions with exceptional properties as a result of what diesel engines have known. - Dos can be operated in a simple and inexpensive manner.

The invention will be illustrated in detail hereinafter with reference to examples and a comparative example, without any intention of which it may impose a restriction.

Examples and Comparative Examples

General Method for Preparing Polymers

600 g of the monomer composition according to the composition detailed in each case in Table 1 and 7-dodecyl mercaptan (20 g to 2 g depending on the desired molecular weight) are mixed. 44.4 g of this monomer / regulator mixture is charged together with 400 g carrier oil (eg 100N mineral oil, synthetic dinonyl adipate or vegetable oil) in the 2 I reaction flask of a stirrer apparatus. saber, condenser, thermometer, power pump and N2 power line. The apparatus is inertia and heated to 100 ° C with the aid of an oil bath. The remaining 555.6 g of the demonomer / regulator mixture is mixed with 1.4 g of tert-butyl peroctoate. When the mixture in the reaction vial reached a temperature of 100 ° C, 0.25 g of tert-butyl peroctoate is added, and Feeding of the monomer / regulator / initiator mixture via a pump is started simultaneously. The addition is carried out uniformly over a period of 210 min at 100 ° C. 2 h after the end of the feed another 1.2 g of tert-butyl peroctoate is added and the mixture is stirred at 100 ° C for another 2 h. A clear 60% concentration is obtained.

The weight average molecular weight Mw and the polydispersion index PDI of the polymers were determined by GPC. Measurements were made on tetrahydrofuran at 35Â ° C against a polymethyl methacrylate calibration curve composed of a set of 25 standards (Polymer Stan- dards Service or Polymer Laboratories), whose Mpeak was distributed in a uniformly uniform manner. over a range of 5x106 to 2x102 g / mol. A combination of six columns (Polimer Standards SDV 100Á / 2xSDVLXL / 2xSDV 100Á / Shodex KF-800D) was used. To record the signal, an Rl detector (Agilent 1100 Series) was used.

Table 1: Properties of Polymers Used

<table> table see original document page 28 </column> </row> <table>

DPMA: alkyl methacrylate which has 12 to 15 noradical alkyl carbon atoms

SMA: alkyl methacrylate which has 16 to 18 noradical carbon atoms alkylMMA: methyl methacrylate

Subsequently, the polymers thus obtained were investigated in a mixture of 80/20 diesel / mineral biodiesel. The amount of polymer used is shown in Table 2. The mineral diesel used was Australian summer diesel with a pour point of -9 ° C. Palm oil methyl ester (PME) (source of crude oil material from Malaysia:) having a pour point of + 12 ° C was used as the biodiesel. An 80/20 mixture of diesel / mineral biodiesel exhibited a flow point of 0 ° C.

To investigate the low temperature properties, the pour point (PP) for ASTM D97 of the mixtures and the diesel fuel was determined. The results obtained are shown in table 2.Table 2: Properties of mineral diesel fuels and mixtures comprising approx. 80% by weight of mineral diesel and approx. 20% by weight of biodiesel, each of which contains polymers comprising ester.

<table> table see original document page 29 </column> </row> <table>

The detailed examples above show that the ester-comprising polymers containing repeating units which are derived from ester monomers having 16 to 40 carbon atoms in the alcohol radical lead to significantly lower low temperature properties of mixtures comprising biodiesel, especially palm oil esters, and mineral diesel.

Particularly surprising preferred mixtures which comprise certain ester-comprising polymers have an improved flow point compared to the unaddressed pure mineral diesel fuel, this improved pour point also being retained in the case of the addition of biodiesel.

Claims (25)

1. Fuel composition comprising at least one diesel fuel of mineral origin and at least one biodiesel fuel, characterized in that the fuel composition contains at least 20% by weight of diesel fuel from 0.05 to 5% by weight. of at least one polymer comprising ester comprising repeating units which are derived from ester monomers having 16 to 40 carbon atoms in the alcohol radical, and repeating units that are derived from ester monomers having 7 to 15 carbon atoms in the radical alcohol. Fuel composition according to Claim 1, characterized in that the ester-comprising polymer is selected from polyalkyl (meth) acrylates (PAMAs), polyalkyl fumarates and / or polyalkyl maleates. Fuel composition according to Claim 1 or -2, characterized in that the ester-comprising polymer contains -0.5 to 60% by weight of units which are derived from ester monomers having 16 to 40 carbon atoms in the radical. alcohol. Fuel composition according to at least one of the preceding claims, characterized in that the polymer comprising ester contains 0.1 to 30% by weight of units which are derived from ester monomers having 1 to 6 carbon atoms in the radical. alcohol. Combustible composition according to at least one of the preceding claims, characterized in that the polymer comprising ester is obtainable by polymerizing a mixture of monomers comprising from 0 to 40% by weight of one or more compounds of ethylenically unsaturated esters of formula (I) wherein R is hydrogen or methyl, R1 is a linear or branched alkyl radical having 1 to 6 carbon atoms, R2 and R3 are each independently hydrogen or a group of the formula -COOR1 wherein R1 is hydrogen or alkyl group having 1 to 6 carbon atoms, - 10 to 98% by weight of one or more ethylenically unsaturated ester compounds of formula (II). ) where R is hydrogen or methyl, R4 is a linear or branched alkyl radical having 7 to 15 carbon atoms, R5 and R6 are each independently hydrogen or a group. of the formula -C OOR "wherein R" is hydrogen or an alkyl group having 7 to 15 carbon atoms, and 0.1 to 80% by weight of one or more ethylenically unsaturated ester compounds of formula (III) <formula> formula see original document where R is hydrogen or methyl, R7 is linear or branched alkyl radical having 16 to 40 carbon atoms, R8 and R9 are each independently hydrogen or a group of the formula -COOR1 "where R ' "is hydrogen or an alkyl group having 16 to 40 carbon atoms. A fuel composition according to at least one of the preceding claims, characterized in that the polymer comprising ester comprises at most 3% by weight of units which are derived from hydroxyl-containing monomers. Combustible composition according to at least one of the preceding claims, characterized in that the polymer comprising ester comprises at most 3% by weight of repeating units which are derived from monomers comprising ester with alcohol radicals. where R is hydrogen or methyl, R10 is an alkyl radical which is substituted by an OH group and has 2 to 20 carbon atoms, or one or more of the acid-containing formula of formula (IV1). wherein R13 and R14 are each independently hydrogen or methyl, R15 is hydrogen or an alkyl radical having 1 to 20 carbon atoms, and η is a number integer from 1 to 30, R 11 and R 12 are each independently hydrogen or a group of the formula -COOR "where -R" is hydrogen or an alkyl radical which is substituted by an OH group having 2 to 20 carbon atoms One, or alkoxylated radical of formula (V) is shown above. A fuel composition according to at least one of the preceding claims, characterized in that the polymer comprising ester has a molecular weight in the range of 40,000 to 600,000 g / mol. Fuel composition according to at least one of the preceding claims, characterized in that the polymer comprising ester has a polydispersion index in the range of 1.0 to 10.0. Fuel composition according to at least one of the preceding claims, characterized in that the ester-comprising polymer has a thickening efficiency of TE100 measured at -100 ° C in the range of 7.5 to 29 mm2 / s. Fuel composition according to at least one of the preceding claims, characterized in that the diesel fuel of mineral origin has a boiling point in the range of 120 ° C to-450 ° C. Fuel composition according to at least one of the preceding claims, characterized in that the diesel fuel of mineral origin has a kinematic viscosity measured at 40 ° C and ASTM D445 in the range of 1 to 5 mm2 / s. Fuel composition according to at least one of the preceding claims, characterized in that the biodiesel fuel comprises fatty acid esters which are derived from monohydric alcohols having 1 to 4 carbon atoms. Fuel composition according to Claim 13, characterized in that the monoester is a methyl ester. Fuel composition according to at least one of the preceding claims, characterized in that the biodiesel fuel comprises at least 35% by weight of saturated acid-fatty esters having at least 16 carbon atoms in the fatty acid radical. Fuel composition according to at least one of the preceding claims, characterized in that the biodiesel fuel is derived from palm oil or animal tallow. Fuel composition according to at least one of the preceding claims, characterized in that the fuel composition comprises at least one additive. Fuel composition according to claim 17, characterized in that at least one additive is selected from the group of dispersants, demulsifiers, defoamers, uri-briciness additives, antioxidants, cetane number enhancers, detergents, dyes, corrosion inhibitors and / or odorants. Fuel composition according to at least one of the preceding claims, characterized in that the fuel composition comprises at least 80% by weight of the die-fuel of mineral origin. Fuel composition according to at least one of the preceding claims, characterized in that the fuel composition contains 0.1 to 1% by weight of at least one polymer comprising ester. Fuel composition according to at least one of the preceding claims, characterized in that the fuel composition consists of -20.0 to 97.95% by weight of diesel fuel of mineral origin, -20 to 79.95% by weight of biodiesel fuel. 0.05 to 5% by weight of polymer comprising ester and 0 to 60% by weight of additives. Fuel composition according to at least one of the preceding claims, characterized in that the fuel composition comprises 0.01 to 0.5% by weight of the ethylene copolymer. Fuel composition according to at least one of the preceding claims, characterized in that the fuel composition comprises at most 0.05% by weight of the ethylene copolymer. 24. Use of ester-comprising polymers comprising repeating units derived from unsaturated esters having 7 to 15 carbon atoms in the alcohol radical, and repeating units derived from unsaturated esters having 16 to 40 noradical alcohol carbon atoms, in a concentration of 0.05 to 5% by weight as flow enhancers in combustible compositions which comprise at least one diesel fuel of mineral origin and at least one biodiesel fuel. Process for the operation of a diesel engine, characterized in that the combustible composition as defined in at least one of claims 1 to 23 is used.