KR20070111366A - Cold flow improvers for vegetable or animal fuel oils - Google Patents

Abstract

Additives for improving the cold flow behavior of fatty acid esters are provided to set CFPP values to -10 deg.C or -20 deg.C or lower such that the CFPP values remain constant even in the case that the oil is stored for a prolonged period in the temperature range of its cloud point and lower by comprising a copolymer of ethylene and at least one acrylic ester or vinyl ester having a melting viscosity(V140) of 80 m.Pas or less. A fuel oil additive comprises: (A) a copolymer of ethylene and 13 to 17 mol % of at least one acrylic ester or vinyl ester having a C1 to C18-alkyl radical and a melting viscosity(V140) of 80 m.Pas or less; and (B) a comb polymer including structural units formed from (B1) at least one olefin as a first monomer, which has at least one C8 to C18-alkyl radical on the olefinic double bond, and (B2) at least one ethylenically unsaturated dicarboxylic acid as a second monomer, which has at least one C8 to C16-alkyl radical bonded through an amide and/or imide group, wherein a parameter Q of a mathematical formula 1 has a value of 23 to 27: wherein w1 is the molar ratio of the respective chain lengths n1 in the alkyl radicals of the first monomer, w2 is the molar ratio of the respective chain lengths n2 in the alkyl radicals of the amide and/or imide groups of the second monomer, n1 are the respective chain lengths in the alkyl radicals of the first monomer, n2 are the respective chain lengths in the alkyl radicals of the amide and/or imide groups of the second monomer, i is the serial variable for the chain lengths in the alkyl radicals of the first monomer, and j is the serial variable for the chain lengths in the alkyl radicals of the amide and/or imide groups of the second monomer.

Description

Cold flow improvers for vegetable or animal fuel oils

The present invention relates to additives, their use as cold flow improvers for vegetable or animal fuel oils, and fuel oils to which the additives have been added.

There is a growing interest in alternative energy sources based on renewable raw materials in view of the reduction in global oil reserves and the destruction of the environment resulting from the use of fossil and mineral fuels. These include in particular natural oils and vegetable or animal fats. These are triglycerides of fatty acids having 10 to 24 carbon atoms which are generally considered to be less harmful to the environment, while their calorie values are comparable to conventional fuels. Biofuels, ie, fuels derived from animal or vegetable materials, are obtained from renewable sources, so when they are burned, they produce only CO ₂ as much as they were previously converted to biomass. It is reported that a smaller amount of carbon dioxide is produced during combustion and very small amounts of sulfur dioxide are produced compared to the same amount of crude distillate fuel, for example diesel fuel. In addition, they are biodegradable.

Oils obtained from animal or vegetable materials are mainly metabolites which generally comprise the triglycerides of the monocarboxylic acids of formula (I).

In Formula 1 above,

R is a saturated or unsaturated aliphatic radical having 10 to 25 carbon atoms.

In general, such oils include glycerides from a series of acids whose acid number and form of acid differ depending on the oil source, which may further comprise phosphoglycerides. Such oils can be obtained by processes known from the prior art.

Due to the often unsatisfactory properties of triglycerides, the industry has often converted natural triglycerides to fatty acid esters of lower alcohols such as methanol or ethanol.

Obstacles to using fatty acid esters of triglycerides and lower monohydric alcohols alone or as a mixture with diesel fuels as substitutes for diesel fuels have been found to be flow behavior at low temperatures. The reason for this is that these oils have a higher degree of heterogeneity than mineral oil middle distillate. For example, the cold filter plugging point (CFPP) of rapeseed oil methyl ester (RME) is -14 ° C. To date, the use of prior art additives has not been able to reliably obtain the CFPP values of -20 ° C. required for use as winter diesel in Central Europe, and CFPP values of -22 ° C. or lower for special applications. This problem is exacerbated when using oils comprising a relatively large amount of saturated fatty acid esters present in, for example, sunflower oil methyl ester, waste oil methyl ester or soybean oil methyl ester.

EP-A-665 873 discloses biofuels; Fuel oils based on crude oil; And a polymer (b) or a polar nitrogen compound (c) in the form of an oil soluble ethylene copolymer (a) or a comb or one or more substantially straight chain alkyl groups having 10 to 30 carbon atoms, providing a straight chain of one or more atoms, Compound (d), or components (a), (b), (c) and (d), in which the atoms are bonded to a nonpolymeric organic radical and comprise a carbon atom of the alkyl group and at least one non-terminal oxygen atom A fuel oil composition is disclosed which contains an additive comprising at least one of (e).

EP-A-O 629 231 describes relatively large amounts of oils consisting essentially of alkyl esters of fatty acids derived from vegetable oils, animal oils or both, and the following components (I) to ( A composition comprising a small amount of mineral oil cold flow improver comprising at least one of VII) is described, provided that the composition is acrylic acid and / or methacrylic derived from any mixture of polymeric esters or alcohols having 1 to 22 carbon atoms. It does not include copolymers of esters of acids.

(I) a comb-form polymer, maleic anhydride or fumaric acid and another ethylenically unsaturated monomer (which may be esterified), or a polymer or copolymer of an α-olefin, or a fumarate or itaconate polymer or Copolymer,

(II) polyoxyalkylene esters, esters / ethers or mixtures thereof,

(III) ethylene / unsaturated ester copolymers,

(IV) polar organic nitrogen-containing paraffin crystal growth inhibitors,

(V) hydrocarbon polymers,

(VI) sulfur-carboxyl compounds and

(VII) aromatic pour point lowering agent modified with hydrocarbon radicals.

European Patent Application Publication No. O 543 356,

Adding (a) 0.001 to 10% by weight, based on the long chain fatty acid ester FAE, of the PPD additive (flow point reducing agent) known per se and used to improve the low temperature performance of mineral oils;

(B) cooling the unadded long chain fatty acid ester FAE below the cold filter occlusion point and

Recovering the resulting precipitate (FAN), starting from esters of natural long-chain fatty acids with monovalent C _1-6 alcohols (FAE) and having improved low temperature performance for use as fuel or lubricant The preparation method of is described.

German Patent Publication No. 40 40 317,

58 to 95% by weight of at least one ester (a) derived from a fatty acid having a iodine number of 50 to 150 and having 12 to 22 carbon atoms and a lower aliphatic alcohol having 1 to 4 carbon atoms,

4 to 40% by weight of one or more esters (b) of fatty acids having 6 to 14 carbon atoms and lower aliphatic alcohols having 1 to 4 carbon atoms, and

A mixture of fatty acid lower alkyl esters having improved low temperature stability is described, comprising from 0.1 to 2% by weight of one or more polymeric esters (c).

EP-A-O 153 176 discloses several crude distillation oil fuel oil an average alkyl chain length of 12 to 14-unsaturated dialkyl as a low temperature flow improver for the C _{4 - 8} dicarboxylate to the use of a polymer as basic substrate It is. As suitable comonomers, mention may be made of unsaturated esters, in particular vinyl acetate, also α-olefins.

In EP-A-0 153 177 Ho, monoethylenically unsaturated C _{4 - 8} monocarboxylic acid or monoethylenically unsaturated C _{4 - 8,} average carbon number of the dicarboxylic acids of the n- alkyl ester (Current n- alkyl ester is 12 to 14 An additive concentrate is disclosed which comprises a combination of copolymer (I) having at least 25% by weight and another unsaturated ester or olefin with another low temperature fluidity improver (II) for distillate fuel oil.

EP 1 491 614 describes vegetable or animal oils and blends of these oils with crude distillate fuel oils, the crude distillate fuel oils comprising at least 17 mole percent vinyl esters and 100 methylenes. Ethylene-vinyl ester copolymers having a branching degree of at least 5 alkyl branches per group are included to improve their low temperature properties.

Known additives include fatty acid esters, particularly fatty acid esters comprising at least 7% by weight of palmitic acid methyl esters and stearic acid methyl esters, at -10 ° C. CFPP and southern central, which are required for use as winter diesel in western central Europe. In Europe, CFPPs of -20 ° C, for special applications, have often been unable to reliably control to have CFPPs of -22 ° C or below. A further problem with existing additives is the lack of low temperature change stability of the added oil. That is, if the oil is stored for a long period of time where the temperature changes in the range below the cloud point, the set CFPP value of the oil gradually rises. In addition, especially oils having a high content of palmitic acid methyl ester and stearic acid methyl ester tend to settle during storage at low temperatures. It is known from practical experience that sedimentation of added fatty acid esters that occur in laboratory experiments under low temperature conditions causes filter clogging in the engine and makes the fuel unsuitable for use, even though CFPP is achieved.

Accordingly, an object of the present invention is, for example, the low temperature fluidity behavior of fatty acid esters derived from rapeseed oil, waste oil, sunflower oil and / or soybean oil and comprising at least 7% by weight of palmitic acid methyl ester and stearic acid methyl ester. It is to provide an additive for improving the CFPP value to be -10 ° C or -20 ° C or less, so that the CFPP value is kept constant even during the long term storage period of the oil in the range below the cloud point. Moreover, these additives should contribute to preventing the settling tendency of these oils so that even after storage of fatty acid esters for several days, the fatty acid esters remain homogeneous and free flowing and their CFPP does not change.

It has now been surprisingly found that additives comprising polymers in the form of ethylene copolymers and combs are significant flow enhancers for the fatty acid esters described above.

The present invention

Copolymer (A) of 13 to 17 mole% of at least one acrylic acid or vinyl ester having a C _1-18 alkyl radical and having a melt viscosity (V ₁₄₀ ) of 80 mPas or less; and

As monomer 1, one or more olefins (B1) having at least one C _8-18 alkyl radical in the olefin double bond, and as monomer 2, having at least one C _8-16 alkyl radical bonded via an amide and / or imide group An additive is provided which comprises a structural unit formed from at least one ethylenically unsaturated dicarboxylic acid (B2) and comprises a comb-form polymer (B) having a parameter Q in formula (1) of 23 to 27.

In Equation 1 above,

w ₁ is the molar ratio of each chain length (n ₁ ) in the alkyl radicals of monomer 1,

w ₂ is the molar ratio of the respective chain length (n ₂ ) in the alkyl radicals of the amide and / or imide groups of monomer 2,

n ₁ is the length of each chain in the alkyl radicals of monomer 1,

n ₂ is the respective chain length in the alkyl radicals of the amide and / or imide groups of monomer 2,

i is the serial variable for each chain length in the alkyl radicals of monomer 1,

j is a serial variable for each chain length in the alkyl radicals of the amide and / or imide groups of monomer 2.

The invention further provides fuel oil compositions comprising animal or vegetable fuel oils and the additives defined above.

The present invention further provides for the use of the additives defined above to improve the low temperature fluidity characteristics of animal or vegetable fuel oils.

The present invention further provides a method for improving the low temperature fluidity characteristics of fuel oils of animal or plant origin by adding the above defined additives to animal or vegetable fuel oils.

In a preferred embodiment of the invention, the value of Q is 24 to 26.

As used herein, the chain length of an olefin means the length of the monomeric olefin minus the number of two olefin bonded carbons. For olefins with non-terminal double bonds, for example for olefins with vinylidene residues, the chain length corresponds to the total chain length of the olefin minus two olefin bonded carbons.

When considering polymers formed from olefins (B1) and dicarboxamide / imides (B2) in addition to monomeric olefins, the chain length is the length of the alkyl radicals introduced into the polymer by the olefins-excluding the polymer backbone.

Suitable ethylene copolymers (A) are preferably copolymers comprising from 13 to 17 mole percent of at least one vinyl ester and / or (meth) acrylic acid ester and from 83 to 87% by weight of ethylene. It is particularly preferred that the ethylene copolymer has 15 to 17 mole percent of one or more vinyl esters. Suitable vinyl esters are derived from fatty acids having straight or branched chain alkyl groups of 1 to 30 carbon atoms. The melt viscosity (V ₁₄₀ ) of the preferred ethylene copolymer is less than 5 mPas, preferably 10 to 80 mPas, in particular 20 to 60 mPas.

Examples of suitable vinyl esters are based on vinyl acetate, vinyl propionate, vinyl butyrate, vinyl hexanoate, vinyl heptanoate, vinyl octanoate, vinyl laurate and vinyl stearate, and branched fatty acids. Esters of vinyl alcohols such as vinyl isobutyrate, vinyl pivalate, vinyl 2-ethylhexanoate, vinyl isononanoate, vinyl neononanoate, vinyl neodecanoate and vinyl neodecanoate have. Esters of acrylic acid and methacrylic acid having 1 to 20 carbon atoms in the alkyl radical as comonomers, for example methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth ) Acrylate, isobutyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate , Tetradecyl (meth) acrylate, hexadecyl (meth) acrylate, octadecyl (meth) acrylate are similarly suitable. Mixtures of two, three, four or more of the comonomers are also suitable.

Further preferred copolymers are, in addition to ethylene, olefins having 13 to 17 mol% of vinyl esters and also 3 to 10 carbon atoms such as propene, butene, isobutylene, hexene, 4-methylpentene, octene and diiso Butylene and / or norbornene from 0.5 to 10 mole percent.

The weight-average molecular weight (Mw) of the copolymer (A) is preferably from 1,000 to 10,000 g / mol, in particular from 1,500 to 5,000 g /, as determined by gel permeation chromatography (GPC) on polystyrene standards in THF. mol. ¹ H NMR spectroscopy of its decomposition as measured by (a solvent CDCl _3, 400MHz) map is preferably less than 6, in particular 5 CH _3/100 CH ₂ group is less than. Methyl groups are derived from short and long chain branches and not from copolymerized comonomers.

Copolymer (A) can be prepared by conventional copolymerization methods such as suspension polymerization, solution polymerization, gas phase polymerization or high pressure bulk polymerization. It is preferable to carry out the high pressure bulk polymerization at a pressure of 50 to 400 mPas, preferably 100 to 300 mPas and at a temperature of 100 to 300 ° C, preferably 150 to 220 ° C. In a particularly preferred production variant, the polymerization is carried out in a multi-zone reactor in which the temperature difference between peroxide feeds along the tubular reactor is kept to a minimum, i.e., below 50 ° C, preferably below 30 ° C, in particular below 15 ° C. The maximum temperature of each reaction zone is preferably different below 30 ° C, more preferably below 20 ° C, in particular below 10 ° C.

The reaction of the monomers is initiated by radical forming initiators (free radical chain initiators). This class of materials includes, for example, oxygen, hydroxide peroxides, peroxides and azo compounds such as cumene hydroperoxide, tert-butyl hydroperoxide, dilauroyl peroxide, dibenzoyl peroxide, bis (2- Ethylhexyl) peroxydicarbonate, tert-butyl perfivalate, tert-butyl permaliate, tert-butyl perbenzoate, dicumyl peroxide, tert-butyl cumyl peroxide, di (tert-butyl Peroxide, 2,2'-azobis (2-methylpropanenitrile), 2,2'-azobis (2-methylbutyronitrile) The initiator is used alone or as a mixture of two or more materials. It is used as 0.01 to 20% by weight, preferably 0.05 to 10% by weight, based on the monomer mixture.

High pressure bulk polymerization is carried out in known high pressure reactors, for example in batch or continuous autoclave or tubular reactors, and tubular reactors have been found to be particularly useful. Aliphatic and / or aromatic hydrocarbons or hydrocarbon mixtures, solvents such as benzene or toluene may be present in the reaction mixture. It is preferably carried out in a substantially solventless procedure. In a preferred embodiment of the polymerization, a mixture of monomers, initiator and modifier (if used) is fed to the tubular reactor through the reactor inlet and also through one or more side branches. Preferred modifiers are, for example, hydrogen, saturated and unsaturated hydrocarbons such as propane, aldehydes such as propionaldehyde, n-butyraldehyde or isobutyraldehyde, ketones such as acetone, methyl ethyl ketone, methyl iso Butyl ketone, cyclohexanone) and alcohols such as butanol. Comonomers and modifiers can also be metered into the reactor together with ethylene or separately metered as sidestream. The monomer stream may have a different composition (EP 2 2 738 and EP 922 716).

Examples of suitable copolymers or terpolymers include the following.

Ethylene-vinyl acetate copolymers having 10 to 40 wt% vinyl acetate and 60 to 90 wt% ethylene;

Ethylene-vinyl acetate-hexene terpolymers, known from German Patent Publication No. 34 43 475;

Ethylene-vinyl acetate-diisobutylene terpolymers, described in EP 0 203 554;

Mixtures of ethylene-vinyl acetate-diisobutylene terpolymers and ethylene / vinyl acetate copolymers, known from EP 0 254 284;

Mixtures of ethylene-vinyl acetate copolymers and ethylene-vinyl acetate-N-vinylpyrrolidone terpolymers described in EP 0 405 270;

Ethylene / vinyl acetate / isobutyl vinyl ether terpolymers described in EP 0 463 518;

Ethylene / vinyl acetate / neononanoate or vinyl neodecanoate containing from 10 to 35% by weight of vinyl acetate and from 1 to 25% by weight of certain neo compounds, in addition to ethylene, known from EP-A-493 769 Terpolymers;

A second vinyl derived from ethylene, a first vinyl ester of up to 4 carbon atoms, and a branched carboxylic acid of up to 7 carbon atoms or a branched, but not tertiary, carboxylic acid of 8 to 15 carbon atoms, described in EP 778 875. Terpolymers of esters;

Terpolymers of ethylene, vinyl esters of one or more aliphatic C _2-20 monocarboxylic acids, and 4-methylpentene-1, described in German Patent Publication No. 196 20 118;

Terpolymers of ethylene, at least one aliphatic C _2-20 monocarboxylic acid and bicyclo [2.2.1] hept-2-ene, described in German Patent Publication No. 196 20 119; And

Terpolymers of at least one olefinically unsaturated comonomer comprising ethylene and at least one hydroxyl group, as described in EP 0 926 168.

Preference is given to using mixtures of the same or different ethylene copolymers. It is more preferred that the polymers based on the mixture differ in one or more properties. For example, they can include different comonomers, different comonomer content, molecular weight and / or branching. The mixing ratio of the different ethylene copolymers is preferably in the range 20: 1 to 1:20, preferably 10: 1 to 1:10, in particular 5: 1 to 1: 5.

Copolymer (B) is preferably derived from amides and imides of ethylenically unsaturated dicarboxylic acids. Preferred dicarboxylic acids are maleic acid, fumaric acid and itaconic acid. Particularly suitable comonomers are monoolefins (B1) having 10 to 20 carbon atoms, in particular 12 to 18 carbon atoms. They are preferably straight-chain and preferably have double bonds at their ends, for example in dodecene, tridecene, tetradecene, pentadecene, hexadecene, heptadecene and octadecene. The ratio of dicarboxamide / imide to olefin (s) in the polymer is preferably in the range from 1: 1.5 to 1.5: 1, with particular equimolar amounts being preferred.

In addition, the copolymer (B) may be the above-mentioned ethylenically unsaturated dicarboxamide / imide and olefin, for example, an olefin having 2 to 50 carbon atoms, allyl polyglycol ether, C _1-30 alkyl (meth) acrylate, vinyl Additional comonomers copolymerizable with aromatic or C _1-20 alkyl vinyl ethers are present in minor amounts of up to 20 mol%, preferably less than 10 mol%, in particular less than 5 mol%. Poly (isobutylene) having a molecular weight of 5,000 g / mol is also used in small amounts, and a highly reactive variant having a high proportion of terminal vinylidene groups is preferred. These additional comonomers are not taken into account in the calculation of the factor parameter Q, which measures the efficiency.

Alkyl polyglycol ethers correspond to the formula

In Formula 2 above,

R ¹ is hydrogen or methyl,

R ² is hydrogen or C _1-4 alkyl,

m is a number from 1 to 100,

R ³ is C _1-24 alkyl, C _5-20 cycloalkyl, C _6-18 aryl or —C (O) —R ⁴ ,

R ⁴ is C _1-40 alkyl, C _5-10 cycloalkyl or C _6-18 aryl.

Copolymers (B) according to the invention are preferably prepared at 50 to 220 ° C, in particular at 100 to 190 ° C. Preferred methods of preparation are solventless bulk polymerization, but aprotic solvents such as benzene, toluene and xylenes or relatively high boiling aromatic, aliphatic or isoaliphatic solvents or solvent mixtures such as kerosene or solvent naphtha. It is also possible to carry out the polymerization in the presence of. Particular preference is given to polymerizing in small aliphatic or isoaliphatic solvents with little effect. The proportion of solvent in the polymerization mixture is generally 10 to 90% by weight, preferably 35 to 60% by weight. In the case of solvent polymerization, the reaction temperature can be adjusted particularly simply by operating through the boiling point of the solvent or under reduced pressure or elevated pressure.

The average molecular weight (Mw) of the copolymer (B) of the invention is generally 1,200 to 200,000 g / mol, in particular 2,000 to 100,000 g, as measured by gel permeation chromatography (GPC) on polystyrene standards in THF. / Mole. Copolymers (B) of the invention should be oil soluble at the relevant doses to be carried out. That is, the additive should be dissolved without residue at 50 ° C. in the oil to be added.

The reaction of the monomers is initiated by radical forming initiators (free radical chain initiators). This class of substances is, for example, oxygen, hydroxide peroxides, peroxides [e.g. cumene hydroperoxide, tert-butyl hydroperoxide, dilauroyl peroxide, dibenzoyl peroxide, bis (2-ethylhexyl) Peroxydicarbonate, tert-butyl perfivalate, tert-butyl permaliate, tert-butyl perbenzoate, dicumyl peroxide, tert-butyl cumyl peroxide, di (tert-butyl) peroxide ], And also azo compounds such as 2,2'-azobis (2-methylpropanonitrile) or 2,2'-azobis (2-methylbutyronitrile). The initiator is used alone or as a mixture of two or more materials, at 0.01 to 20% by weight, preferably 0.05 to 10% by weight, based on the monomer mixture.

The copolymer may react maleic acid, fumaric acid and / or itaconic acid or its anhydride with the corresponding amine and subsequently copolymerize or copolymerize the olefin (s) with one or more unsaturated dicarboxylic acids or derivatives thereof, such as itaconic acid. It can be prepared by copolymerizing with anhydride and / or maleic anhydride and subsequently reacting with an amine. It is preferred to carry out copolymerization with anhydrides and convert the obtained copolymers into amides and / or imides after preparation.

In both cases, the reaction with amines is carried out, for example, by reacting 0.8 to 2.5 moles of amine per mole of anhydride, preferably 1.0 to 2.0 moles at 50 to 300 ° C. When using approximately 1 mole of amine per mole of anhydride, monoamines which additionally contain one carboxyl group per amide group are preferentially formed at reaction temperatures of about 50 to 100 ° C. At higher reaction temperatures of about 100 to 250 ° C., the amide is preferably formed from primary amines while removing water. When using a large amount of amine, preferably when using 2 moles of amine per mole of anhydride, the amide salt-ammonium salt is formed at approximately 50 to 200 ° C. and the diamine is at a higher temperature, for example 100 to 300 ° C. It is preferably formed at 120 to 250 ℃. The reaction water may be distilled off by an inert gas stream or by azeotropic distillation in the presence of an organic solvent. For this purpose, 20 to 80% by weight, in particular 30 to 70% by weight, in particular 35 to 55% by weight, of at least one organic solvent is preferably used. Herein, copolymers having an acid value of 30 to 70 mg KOH / g, preferably 40 to 60 mg KOH / g (diluted by 50% in solvent) are considered monoamides. Corresponding copolymers having an acid value of less than 40 mg KOH / g, in particular less than 30 mg KOH / g, are considered as diamides or imides. Monoamides and imides are particularly preferred.

Suitable amines are primary and secondary amines having one or two C _8-16 alkyl radicals. These may be one, two or three amino groups bonded via an alkylene radical having 2 or 3 carbon atoms. Monoamines are preferred. In particular, they have straight chain alkyl radicals, but they may also comprise small amounts (eg 1 or 2 positions) of branched amines, for example up to 30% by weight, preferably up to 20% by weight, in particular up to 10% by weight. . Short or long chain amines can be used, but their proportion is preferably less than 20 mol%, in particular less than 10 mol%, for example 1 to 5 mol%, based on the total amount of amines used.

Particularly preferred primary amines are octylamine, 2-ethylhexylamine, decylamine, undecylamine, dodecylamine, n-tridecylamine, isotridecylamine, tetradecylamine, pentadecylamine, hexadecylamine and these Is a mixture of.

Preferred secondary amines are dioctylamine, dinonylamine, didecylamine, didodecylamine, ditetradecylamine, dihexadecylamine, and also amines having different alkyl chain lengths [e.g., N-octyl-N-decylamine , N-decyl-N-dodecylamine, N-decyl-N-tetradecylamine, N-decyl-N-hexadecylamine, N-dodecyl-N-tetradecylamine, N-dodecyl-N-hexa Decylamine, N-tetradecyl-N-hexadecylamine]. According to the invention, in addition to C _8-16 alkyl radicals, secondary amines with shorter side chains (eg methyl or ethyl groups) of 1 to 5 carbon atoms are also suitable. For secondary amines, what is considered as alkyl chain length (n) in the calculation of parameter Q is the average alkyl chain length of C _8-16 . If present, none of the short or long chain alkyl radicals are taken into account in the calculation of the parameter Q since they do not contribute to the efficiency of the additive.

Particularly preferred copolymers (B) are the monoamides and diamides of primary monoamines as monomer 2.

When a mixture of different olefins and a mixture of different amines is used in the amidation or imidization during the polymerization, the efficiency can be further adjusted for the particular fatty acid ester composition.

In a preferred embodiment, the additives may comprise, in addition to components (A) and (B), also polymers and copolymers based on C _10-24 alkyl acrylates or methacrylates (component C). These poly (alkyl acrylates) and methacrylates have a molecular weight (Mw) of 800 to 1,000,000 g / mol, preferably caprylic alcohol, caproic alcohol, undecyl alcohol, lauryl alcohol, myristyl alcohol, cetyl Alcohol, palmitoleyl alcohol, stearyl alcohol or mixtures thereof, such as coconut alcohol, palm alcohol, tallow fatty alcohol or behenyl alcohol.

In a preferred embodiment, mixtures of the above copolymers (B) are used, but the average of parameter Q of the mixture components is estimated to be a value of 23 to 27, preferably 24 to 26.

The mixing ratio (weight ratio) of the additive component (A) and the component (B) of the present invention is 20: 1 to 1:20, preferably 10: 1 to 1:10, especially 5: 1 to 1; 5. The proportion of component (C) in the formulation consisting of component (A), component (B) and component (C) is 40% by weight, based on the total weight of component (A), component (B) and component (C). Up to%, preferably less than 20% by weight, in particular 1 to 10% by weight.

The additive of the invention is added to the oil at 0.001 to 5% by weight, preferably 0.005 to 1% by weight, in particular 0.01 to 0.5% by weight. They are used as such or in solvents such as aliphatic and / or aromatic hydrocarbons or hydrocarbon mixtures such as toluene, xylene, ethylbenzene, decane, pentadecane, petroleum fractions, kerosene, naphtha, diesel, heating oil, iso paraffin or a commercially available mixture of solvents [for example, solvent naphtha, dihydro-sol ^® (Hydrosol) A 200 N, swelsol ^® (Shellsol) 150 ND, Caro Max ^® (Caromax) 20 LN, swelsol ^® AB, Solvesso small ^® (Solvesso) 150, bovine Solvesso ^® 150 ND, Solvesso ^® 200 cows, may be used by dissolving or dispersing the eksol ^® (Exxsol), isopropyl Parr ^® (Isobar) and swelsol ^® D type. They are preferably dissolved in animal or vegetable fuel oils based on fatty acid alkyl esters. The additives of the invention preferably comprise 1 to 80% of solvents, in particular 10 to 70%, in particular 25 to 60%.

In a preferred embodiment, the fuel oil, often also referred to as biodiesel or biofuel, comprises fatty acid alkyl esters consisting of fatty acids having 12 to 24 carbon atoms and alcohols having 1 to 4 carbon atoms. Typically, relatively high proportions of fatty acids contain one, two or three double bonds.

Examples of oils derived from animal or vegetable materials and which can use the additives of the present invention include rapeseed oil, coriander oil, soybean oil, cottonseed oil, sunflower oil, castor oil, olive oil, peanut oil, corn oil, almond oil, palm kernel oil, Coconut oil, mustard seed oil, tallow, bone oil, fish oil and waste cooking oil. Further examples include oils derived from wheat, jute, sesame, butternut fruit, peanut oil and linseed oil. Fatty acid alkyl esters, also referred to as biodiesel, can be derived from the aforementioned oils by processes known in the art. Rapeseed oil, which is a mixture of fatty acids partially esterified with glycerol, is preferred because it can be obtained in a simple manner by overcompression of rapeseed in large quantities. Similarly widely used waste oil, palm oil, sunflower oil and soybean oil, and also mixtures of these with rapeseed oil are preferred.

Lower alkyl esters of fatty acids are particularly suitable as biofuels. These are, for example, fatty acids having 14 to 22 carbon atoms, for example, lauric acid, myristic acid, palmitic acid, palmitoleic acid, each preferably having an iodine value of 50 to 150, in particular 90 to 125, Of ethyl, propyl, butyl, in particular methyl esters of stearic acid, oleic acid, ellide acid, petroleum acid, ricinolic acid, eliostearic acid, linoleic acid, riolenic acid, eicosane acid, gadoleic acid, docosanoic acid or erucic acid Commercially available mixtures. Mixtures having particularly advantageous properties are mixtures containing 16 to 22 carbon atoms, mainly methyl esters of fatty acids having one, two or three double bonds, ie at least 50% by weight. Preferred lower alkyl esters of fatty acids are the methyl esters of oleic acid, linoleic acid, linolenic acid and erucic acid.

Commercial mixtures of this mentioned form are obtained, for example, by hydrolyzing and esterifying animal and vegetable fats and oils with lower aliphatic alcohols or by transesterification. Similarly, waste cooking oil is suitable as a starting material. To prepare lower alkyl esters of fatty acids, it is advantageous to start with fats and oils high in iodine value, for example sunflower oil, rapeseed oil, coriander oil, castor oil, soybean oil, cottonseed oil, peanut oil or tallow. . Lower alkyl esters of fatty acids based on a novel form of rapeseed oil are preferred, and at least 80% of the fatty acid components are derived from unsaturated fatty acids having 18 carbon atoms.

Thus, biofuels are oils obtained from vegetable or animal substances or both or derivatives thereof which may be useful as fuels and in particular as diesel or heating oils. Although many of these oils can be used as biofuels, vegetable oil derivatives are preferred first, particularly preferred biofuels are alkyl ester derivatives of rapeseed oil, cottonseed oil, soybean oil, sunflower oil, olive oil or palm oil, and rapeseed oil Very particular preference is given to methyl esters, sunflower oil methyl esters, palm oil methyl esters and soybean oil methyl esters. Due to the high demand for biofuels, more manufacturers are moving from fatty acid methyl esters to other highly available raw material sources. Particular mention may be made of waste oils which are used in the form of waste oil methyl esters as a blend with biodiesel alone or with other fatty acid methyl esters such as rapeseed oil methyl ester, sunflower oil methyl ester, palm oil methyl ester and soybean oil methyl ester. Mention may also be made of rapeseed oil methyl esters and soybean oil methyl esters or mixtures of rapeseed oil methyl esters or mixtures of soybean oil methyl esters and palm oil methyl esters.

The additives are introduced and added to the oil according to processes known in the prior art. If more than one additive component or coadditive component is used, the components can be introduced separately or together in any combination with the oil.

The additives of the present invention adjust the CFPP values of biodiesel to CFPP values of -10 ° C and -20 ° C, in some cases up to -25 ° C, as required by market requirements for use in winter, in particular. Likewise, the pour point of biodiesel is lowered by the addition of the additives of the present invention. The additives of the present invention are in oils in question containing a high proportion of at least 7% of esters of saturated fatty acid palmitic acid and stearic acid, for example, in fatty acid methyl esters obtained from regenerated sunflower oil and soybean oil. Particularly advantageous. Thus, using the additives of the present invention, the CFPP value of a mixture of rapeseed oil methyl ester and / or waste oil methyl ester and / or sunflower oil methyl ester and / or soybean oil methyl ester is adjusted to -10 ° C, or -20 ° C. It may be. In addition, the oil to which the additive is added in this way has excellent low temperature change stability. That is, even when the CFPP value is stored under winter conditions, it remains constant and does not tend to precipitate at a constant low temperature (eg -10 ° C or -22 ° C).

In order to produce additive packages for particular solutions in question, the additives of the present invention may be used with one or more oil soluble coadditives only to improve the cold flow properties of crude oil, lubricant oil or fuel oil. Examples of such coadditives are polar compounds (paraffin dispersants) that disperse paraffins and oil soluble amphoterics.

The additives of the present invention can be used in mixtures with paraffin dispersants. Paraffin dispersants have the effect of reducing the size of the paraffin crystals and dispersing them in colloidal form, while apparently reducing the precipitation tendency of the particles, rather than sedimenting the paraffin particles. Useful paraffinic dispersants have been found as both low molecular weight and polymeric oil soluble compounds with ionic or polar groups, for example as amine salts and / or amides. Particularly preferred paraffinic dispersants include the reaction products of secondary fatty amines having 20 to 44 carbon atoms, in particular dicocoamines, diuji fatty amines, distearylamines and dibehenylamines with carboxylic acids and their derivatives. Particularly useful paraffinic dispersants are paraffinic dispersants obtained by reacting aliphatic or aromatic amines, preferably long chain aliphatic amines with aliphatic or aromatic monocarboxylic acids, dicarboxylic acids, tricarboxylic acids or tetracarboxylic acids or their anhydrides. See US Patent No. 4,211,534. Ho]. As paraffin dispersants, amide salts and ammonium salts of aminoalkylene polycarboxylic acids and secondary amines, such as nitrilotriacetic acid or ethylenediaminetetraacetic acid, are likewise suitable (see EP 0 398 101). Other paraffin dispersants are copolymers of α, β-unsaturated compounds with maleic anhydride which can optionally react with primary monoalkylamines and / or aliphatic alcohols (see EP 0 154 177) and alkenyl A reaction product of spiro-bislactone with an amine [European Patent Publication No. 0 413 279 B1] and European Patent Publication No. 0 606 055 A2, α, β-unsaturated dicarboxylic anhydride, α, reaction products of terpolymers based on? -unsaturated compounds and polyoxyalkylene ethers of lower unsaturated alcohols.

The mixing ratio (based on the weight part) of the additive of the present invention and the paraffin dispersant is 1:10 to 20: 1, preferably 1: 1 to 10: 1.

The oil treated with the additive of the present invention can be added to heavy oils obtained from crude oil. The mixture of heavy oil and biofuel thus obtained can be mixed with low temperature additives such as flow enhancers or wax dispersants and also performance packages.

The mixing ratio between biofuel and heavy oil may be 1:99 to 99: 1. It is particularly preferable that the mixing ratio of biofuel: heavy oil is 3:97 to 30:70.

Heavy oil means in particular mineral oils such as kerosene, jet fuels, diesel and heating oils obtained by distilling crude oil and heating at 120 to 450 ° C. Preference is given to using such heavy oils containing up to 0.05% by weight of sulfur, more preferably less than 350 ppm, in particular less than 200 ppm, in particular cases less than 50 ppm. They are generally heavy oils containing only minor amounts of polyaromatic and polar compounds since they are purified under hydrogenation conditions. These are preferably heavy oils having a 95% distillation point below 370 ° C., in particular 350 ° C., in particular cases below 330 ° C. Suitable heavy oils are also synthetic fuels made available by the Fischer-Tropsch process.

These additives may be used alone or in addition to other additives, for example, other pour point lowering or dewaxing aids, antioxidants, cetane number improvers, haze removers, demulsifiers, detergents, dispersants, antifoams, dyes, corrosion inhibitors, conductivity enhancers, sludge inhibitors. , Deodorant and / or additives for cloud point reduction.

Example

Properties of Ethylene Copolymers Used Example Comonomer (s) V ₁₄₀ CH _3/100 CH2 Vinyl ester content A1 (C) Ethylene / VAC / Vinyl Neodecanoate 110 mPas 4.2 13.3 mol% A2 Ethylene / VAC 35 mPas 3.9 16.6mol% A3 (C) Ethylene / VAC 154 mPas 3.0 16.7 mol% A4 (C) Ethylene / VAC 125 mPas 3.0 13.8mol%

VAC = vinyl acetate

Vinyl ester content is determined by pyrolysis and subsequent titration.

Viscosity (V ₁₄₀ ) is measured with a Haake Reostress 600 viscometer. Branching (CH _3/100 CH ₂₎ is calculated by measurement in ¹ H NMR in CDCl ₃ units in 40OMHz, integrate each signal.

Characteristics of the polymer in the form of the comb used Example Comonomer Amine Q Acid value [mg KOH / g] B1 MSA-Co-C ₁₄ / _16- α-olefins (1: 0.5: 0.5) C ₁₂ amine 25 2 B2 MSA-Co-C ₁₄ / _16- α-olefins (1: 0.5: 0.5) C ₁₄ amine 25.0 57

Acrylate C1  Poly (octadecyl acrylate), K value 32 C2  Poly (vehenyl acrylate), K value 18

Characteristics of the test oil Oil number CFPP [℃] Furtherance E1 -8 SoyaME / RME 30:70 E2 -7 RME / PME 85:15 E3 -11 RME / AME 60:40 E4 -10 RME / AME 50:50 E5 -8 RME / AME 40:60 E6 -8 RME / AME 45:55

SoyaME = Soybean Methyl Ester

RME = rapeseed oil methyl ester

PME = palm oil methyl ester

AME = waste oil methyl ester

Methyl Ester Distribution of Test Oil E1 E2 E3 E4 E5 E6 C16: 0 6.53 6.21 6.74 7.33 8.13 7.76 C18: 0 1.19 2.36 2.71 2.97 3.32 3.16 C18: 1 45.19 48.73 52.56 50.84 45.36 46.77 C18: 2 36.33 28.77 26.45 28.17 32.27 31.00 C18: 3 8.37 9.18 6.36 5.49 5.45 5.89 C20: 1/2/3 0.79 1.25 1.14 1.04 0.97 1.03 C20: 0 0.39 0.57 0.58 0.56 0.53 0.57 C22: 0 0.15 0.39 0.48 0.51 0.50 0.49

In the table below, the mixing ratio depending on the weight of additive A, additive B and additive C is A: B = 4: 1 or, if C is present in the mixture, A: B: C = 4: 1: 0.2. The total amount of additives is listed in the first line of the table.

CFPP test on test oil E1 Example Polymer in the form of a comb Ethylene copolymer Polyacrylate 2,000 ppm 3,000 ppm 4,000ppm One B1 A2 - -18 -22 -20 2 (C) B1 A1 - -12 -16 -10 3 B1 A2 C3 -18 -21 -21

CFPP test on test oil E2 Example Polymer in the form of a comb Ethylene copolymer Polyacrylate 2,000 ppm 3,000 ppm 4,000ppm 4 (C) B1 A4 - -6 -10 -10 5 B1 A2 C1 -8 -10 -11

CFPP test on test oil E3 Example Polymer in the form of a comb Ethylene copolymer Polyacrylate 2,000 ppm 3,000 ppm 6 B1 A2 - -20 -23 7 (C) B1 A4 - -17 -19

CFPP test on test oil E4 Example Polymer in the form of a comb Ethylene copolymer Polyacrylate 2,000 ppm 3,000 ppm 8 B1 A2 - -17 -22 9 (C) B2 A3 - -14 -17

CFPP test on test oil E5 Example Polymer in the form of a comb Ethylene copolymer Polyacrylate 2,000 ppm 3,000 ppm 10 B1 A2 - -13 -18 11 B1 A2 C2 -13 -18 12 (C) B2 A3 - -11 -13

CFPP test on test oil E6 Example Polymer in the form of a comb Ethylene copolymer Polyacrylate 4,000ppm 13 B1 A2 - -19 14 B1 A2 C2 -19 15 (C) B1 A3 - -16

The present invention relates to the low temperature fluidity behavior of fatty acid esters derived from rapeseed oil, waste oil, sunflower oil and / or soybean oil and comprising at least 7% by weight of palmitic acid methyl ester and stearic acid methyl ester, the CFPP value being -10 ° C or An additive for improving is set below −20 ° C. and so that the CFPP value remains constant during long term storage of oil in the range below cloud point. Moreover, these additives contribute to preventing the sedimentation tendency of these oils so that even after storage of fatty acid esters for several days, the fatty acid esters are free flowing and the CFPP of these fatty acid esters does not change.

Claims (15)

Copolymer (A) of 13 to 17 mole% of at least one acrylic acid or vinyl ester having a C _1-18 alkyl radical and having a melt viscosity (V ₁₄₀ ) of 80 mPas or less; and As monomers one double bond, one or more of the olefinic C _{8 - 18} of a second one or more olefin (B1) and the monomer having an alkyl radical, an amide and / or already bonded through a de Group C _{8 -} at least one having at least one ₁₆ alkyl radical, A fuel oil additive comprising a polymer (B) in the form of a comb comprising structural units formed from ethylenically unsaturated dicarboxylic acids (B2) and having a parameter Q of formula 1 of 23 to 27. Equation 1

In Equation 1 above, w ₁ is the molar ratio of each chain length (n ₁ ) in the alkyl radicals of monomer 1, w ₂ is the molar ratio of the respective chain length (n ₂ ) in the alkyl radicals of the amide and / or imide groups of monomer 2, n ₁ is the length of each chain in the alkyl radicals of monomer 1, n ₂ is the respective chain length in the alkyl radicals of the amide and / or imide groups of monomer 2, i is the serial variable for each chain length in the alkyl radicals of monomer 1, j is a serial variable for each chain length in the alkyl radicals of the amide and / or imide groups of monomer 2. The fuel oil additive of claim 1 wherein the Q value is 24 to 26. 3. The fuel oil additive according to claim 1 or 2, wherein component (A) comprises 15 to 17 mole percent of one or more vinyl esters. The fuel oil additive according to any one of claims 1 to 3, wherein component (A) comprises 0.5 to 10 mol% of olefins having 3 to 10 carbon atoms. Claim 1 to claim 4, wherein according to any one of the preceding, the component (A) the branching 6 CH _3/100 CH ₂ group is less than the fuel oil additive of the measurement by ¹ H NMR spectrometry in. The fuel oil additive according to any one of claims 1 to 5, wherein the olefin forming component (B1) is an α-olefin. The fuel oil additive according to any one of claims 1 to 6, wherein the molar ratio of comonomer (B1) to comonomer (B2) in the copolymer (B) is from 1.5: 1 to 1: 1.5. The copolymer (B) and the comonomer (B1) and the comonomer (B2) according to any one of claims 1 to 7 also have 2 carbon atoms in addition to the comonomer (B1) and the comonomer (B2). Further comonomers selected from olefins of from 50 to 50, allyl polyglycol ethers, C _1-30 alkyl (meth) acrylates, vinylaromatic or C _1-20 alkyl vinyl ethers, and polyisobutenes having a molecular weight of up to 5,00 g / mol A fuel oil additive comprising less than 20 mol%. The fuel oil additive according to any one of claims 1 to 8, wherein the melt viscosity (V ₁₄₀ ) of component (A) is 5 to 80 mPa. The fuel oil additive according to any one of claims 1 to 9, wherein the molecular weight of component (A) is 1, OO0 to 10,000 g / mol. The fuel oil additive according to any one of claims 1 to 10, wherein the molecular weight of component (B) is 1,200 to 200,000 g / mol. A fuel oil composition comprising a vegetable or animal fuel oil and a fuel oil additive according to any one of claims 1 to 10. The fuel oil composition of claim 12 comprising a mixture of fatty acid esters of C _1-4 alcohols. The fuel oil composition of claim 13, wherein the fatty acid ester comprises stearic acid methyl ester and palmitic acid methyl ester in a proportion of up to 7% by weight. Use of a fuel oil additive according to any one of claims 1 to 11 for improving the low temperature behavior of vegetable or animal fuel oils.