WO2008113757A1

WO2008113757A1 - Mixture of cold flow improvers and amines

Info

Publication number: WO2008113757A1
Application number: PCT/EP2008/053080
Authority: WO
Inventors: Ansgar Eisenbeis; Irene Trötsch-Schaller; Uwe Rebholz
Original assignee: Basf Se
Priority date: 2007-03-22
Filing date: 2008-03-14
Publication date: 2008-09-25
Also published as: AR067237A1; BRPI0808949A2; EP2129752A1

Abstract

The invention relates to a mixture having 5 to 95 wt.-% of at least one organic compound that is able to improve the cold flow behavior of fuels, and 5 to 95 wt-% of at least one hydrocarbyl-substituted primary or secondary monoamine or polyamine. Said mixture is suitable as an additive to fuels, particularly biofuel oils.

Description

Mixture of cold flow improvers and amines

description

The present invention relates to a mixture containing

(A) 5 to 95 wt .-% of at least one organic compound which is able to improve the cold flow behavior of fuels, and

(B) 5 to 95 wt .-% of at least one amine of the general formula I.

R ¹ R ² HN (I)

in which R ^{1 is} a hydrocarbyl radical having 6 to 40 carbon atoms, which may contain even more primary and / or secondary and / or tertiary amino functions, and R ² denotes a hydrocarbyl radical having 6 to 40 carbon atoms or hydrogen, wherein R ¹ and R ² together can also form a 5- to 7-membered ring,

the sum of components (a) and (b) being 100% by weight.

Furthermore, the present invention relates to the use of this mixture as an additive to fuels, such fuels themselves and fuel additive concentrates containing this mixture dissolved in a hydrocarbon solvent. In particular, the fuels mentioned have a biodiesel component or consist of biodiesel.

Middle distillate fuels of fossil origin, especially gas oils, diesel oils or light fuel oils derived from petroleum, have different levels of paraffins depending on the source of the crude oil. At low temperatures cloudy point or Cloud Point ("CP") precipitates solid paraffins. Upon further cooling, the platy n-paraffin crystals form a kind of "house of cards structure" and the middle distillate fuel stagnates, although its predominant part is still liquid. The precipitated n-paraffins in the temperature range between cloud point (cloud point) and pour point ("PP") significantly affect the flowability of middle distillate fuels; The paraffins clog filters and cause uneven or completely interrupted fuel supply to the combustion units. Similar disturbances occur with light fuel oils.

It has long been known that by suitable additives, the crystal growth of n-paraffins can be modified in middle distillate fuels. Well-acting additives prevent middle distillate fuels from reaching temperatures a few degrees Celsius below the temperature at which the first paraffin crystals crystallize, already become firm. Instead, fine, well crystallizing, separate paraffin crystals are formed, which also pass on further lowering of the temperature filter in motor vehicles and heating systems or at least form a permeable for the liquid part of the middle distillates filter cake, so that trouble-free operation is ensured. The effectiveness of the flow improvers is usually expressed in accordance with the European standard EN 1 16 indirectly by measuring the CoId Filter Plugging Point ("CFPP"). As such cold flow improvers or Middle Distillate Flow Improvers ("MDFI"), for example, ethylene-vinyl carboxylate copolymers such as ethylene-vinyl acetate copolymers ("EVA") are used.

A disadvantage of these additives is that the paraffin crystals thus modified, due to their higher density compared to the liquid part, tend to settle more and more at the bottom of the container when storing the middle distillate fuel. As a result, a homogeneous low-paraffin phase forms in the upper container part and a two-phase paraffin-rich layer at the bottom. Since the deduction of the fuel usually takes place slightly above the container bottom both in the vehicle tanks and in storage or delivery tanks of the mineral oil dealer, there is the risk that the high concentration of solid paraffins leads to blockages of filters and metering devices. This danger increases the further the storage temperature falls below the extinction temperature of the paraffins, since the amount of paraffin precipitated increases with decreasing temperature. In particular, levels of biodiesel also enhance this undesirable tendency of the middle distillate fuel to paraffin sedimentation.

The additional use of paraffin dispersants or wax anti-settling additives ("WASA") can reduce the problems described.

With decreasing world oil reserves and discussions about the environmental impact of fossil and mineral fuel consumption, there is a growing interest in alternative energy sources based on renewable raw materials. These include, in particular, natural oils and fats of plant or animal origin. These are in particular triglycerides of fatty acids having 10 to 24 carbon atoms which are converted to lower alkyl esters such as methyl esters. These esters are also commonly referred to as "FAME" (Fatty Acid Methyl Ester).

As with middle distillates of fossil origin precipitate during cooling of such FAME crystals, which can also enforce automotive filters and dosing. However, these crystals do not consist of n-paraffins but of fatty acid esters. Nevertheless, fuels based on FAME can be characterized with the same characteristics as the middle distillates of fossil origin (CP, PP, CFPP). The mentioned FAME and mixtures of these FAME with middle distillates generally have a worse low-temperature behavior than middle distillates of fossil origin alone. The addition of FAME tends to produce paraffin sediments in mixtures with middle distillates of fossil origin. In particular, however, if the FAME are to partially or completely replace middle distillates of fossil origin as biofuel oils, they have too high CFPP values, so that they can not easily be used as fuel or heating oil in accordance with the applicable country and region specific requirements , Also, the increase in viscosity on cooling affects the cold property of FAME more than that of middle distillates of fossil origin.

Additives have already been proposed which are intended to improve the cold properties of fuels based on FAME. Thus, in WO 93/18115, conventional cold flow improvers for middle distillates of fossil origin, for example ethylene-vinyl acetate copolymers ("EVA") or polar organic nitrogen-containing compounds such as amine salts, amides, cyclic compounds with tertiary amino groups or condensates are long-chain primary or secondary amines with carboxylic acid-containing polymers, also as cold flow improvers for biofuel oils, for example rapeseed oil methyl ester ("RME"), recommended. The reduction of CFPP values in biofuel oil described therein (with a dosing rate of 1000 ppm of an EVA mixture, a CFPP value of only -18 ° C in RME is achieved), however, in view of the problem-free handling of the fuels not enough.

The object was to make available products which bring about improved cold behavior in fuels based on biofuel ("biodiesel"), which is based on fatty acid esters (FAME). In particular, the CFPP value for such fuel should be effectively lowered.

The object is achieved by the above-mentioned mixture of components (a) and (b), which is all the more surprising because when adding the component (b) to middle distillates of purely fossil origin, which already contain the component (a) , as a rule, an undesirable increase in CFPP levels is observed. The amine component (b) usually alone has virtually no influence on the cold properties of fuels; in the present invention, it acts as a "booster" for component (a), to lower CFPP levels.

The mixture according to the invention preferably contains from 25 to 90% by weight, in particular from 35 to 80% by weight, in particular from 50 to 70% by weight, of the cold flow improver component (a) and from 10 to 75% by weight, in particular 20 to 65 wt .-%, especially 30 to 50 wt .-%, of the amine component (a). As component (a), in principle, all organic compounds can be used which are able to improve the cold flow behavior of fuels. Conveniently, they must have sufficient oil solubility. In particular, cold flow improvers (MDFI) used for this purpose are usually suitable for middle distillates of fossil origin, that is to say for customary diesel fuels and heating oils. However, as component (a) it is also possible to use organic compounds which, when used in customary diesel fuels and heating oils, have partly or predominantly the properties of a wax anti-settling additive (WASA). Also, they can act partly or predominantly as nucleators. It is also possible to use mixtures of organic compounds which are active as MDFI and / or which act as WASA and / or nucleators, as component (a).

In a preferred embodiment, the mixture according to the invention contains as component (a) at least one organic compound selected from

(a1) copolymers of a C2 to C4o olefin with at least one further ethylenically unsaturated monomer; (a2) comb polymers; (a3) polyoxyalkylenes;

(a4) polar nitrogen compounds;

(a5) sulfocarboxylic acids or sulfonic acids or their derivatives; and

(a6) poly (meth) acrylic esters.

Mixtures of different representatives from one of the respective classes (a1) to (a6) as well as mixtures of representatives from different classes (a1) to (a6) can be used.

Suitable C 2 - to C 4 olefin monomers for the copolymers of class (a1) are, for example, those having 2 to 20, in particular 2 to 10, carbon atoms and having 1 to 3, preferably 1 or 2, in particular having one carbon-carbon atom. double bond. In the latter case, the carbon-carbon double bond can be arranged both terminally (α-olefins) and internally. However, preference is given to α-olefins, more preferably α-olefins having 2 to 6 carbon atoms, for example propene, 1-butene, 1-pentene, 1-hexene and, above all, ethylene.

In the copolymers of class (a1), the at least one further ethylenically unsaturated monomer is preferably selected from carboxylic alkenyl esters, (meth) acrylic esters and further olefins.

If further olefins are polymerized in, these are preferably higher molecular weight than the abovementioned C 2 - to C 4 -olefin base monomers. For example, set As olefin base monomer ethylene or propene, suitable as further olefins in particular C10 to C4o-α-olefins. Other olefins are polymerized in most cases only when monomers with carboxylic acid ester functions are used.

Suitable (meth) acrylic esters are, for example, esters of (meth) acrylic acid with C 1 - to C 20 -alkanols, in particular C 1 -C 10 -alkanols, especially with methanol, ethanol, propanol, isopropanol, n-butanol, sec-butanol, isobutanol, tert-butanol, pentanol, hexanol, heptanol, octanol, 2-ethylhexanol, nonanol and decanol and structural isomers thereof.

Suitable carboxylic alkenyl esters are, for example, C2 to C6 alkenyl esters, e.g. the vinyl and propenyl esters of carboxylic acids having from 2 to 21 carbon atoms, the hydrocarbon radical of which may be linear or branched. Preferred among these are the vinyl esters. Among the carboxylic acids having a branched hydrocarbon radical, preferred are those whose branch is in the α-position to the carboxyl group, the α-carbon atom being particularly preferably tertiary, ie. H. the carboxylic acid is a so-called neocarboxylic acid. Preferably, however, the hydrocarbon radical of the carboxylic acid is linear.

Examples of suitable carboxylic alkenyl esters are vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, vinyl neopentanoate, vinyl hexanoate, vinyl neononanoate, vinyl neodecanoate and the corresponding propenyl esters, the vinyl esters being preferred. A particularly preferred alkyl alkynyl ester is vinyl acetate; typical copolymers of group (d) resulting therefrom are ethylene-vinyl acetate copolymers (EVA).

In a very particularly preferred embodiment, the mixture according to the invention contains as component (a1) at least one such ethylene-vinyl acetate copolymer. Particularly advantageous ethylene-vinyl acetate copolymers and their preparation are described in WO 99/29748.

Also suitable as copolymers of class (a1) are those which comprise two or more mutually different carboxylic acid alkenyl esters in copolymerized form, these differing in the alkenyl function and / or in the carboxylic acid group. Also suitable are copolymers which, in addition to the carboxylic acid alkenyl ester (s), contain at least one olefin and / or at least one (meth) acrylic acid ester in copolymerized form.

In a further very particularly preferred embodiment, the mixture according to the invention contains as component (a1) at least one terpolymer of a C 2 - to C 4 -α-olefin, a C 1 - to C 20 -alkyl ester of an ethylenically unsaturated monocarboxylic acid acid having 3 to 15 carbon atoms and a C2 to C30 alkenyl ester of a saturated monocarboxylic acid having 2 to 21 carbon atoms. Such terpolymers are described in WO 2005/054314. A typical such terpolymer is composed of ethylene, 2-ethylhexyl acrylate and vinyl acetate.

The one or more ethylenically unsaturated monomers are present in the copolymers of class (a1) in an amount of preferably from 1 to 50% by weight, in particular from 10 to 45% by weight and in particular from 20 to 40% by weight, copolymerized based on the Gesamtcopo- polymer. The majority by weight of the monomer units in the copolymers of class (a1) thus usually comes from the C2 to C4o-basic olefins.

The copolymers of class (a1) preferably have a number-average molecular weight M _{n of} from 1,000 to 20,000, more preferably from 1,000 to 10,000 and in particular from 1,000 to 8,000.

Comb polymers suitable as component of class (a2) are, for example, those described in WO 2004/035715 and in Comb-Like Polymers, Structure and Properties, N.A. Plate and V.P. Shibaev, J. Poly. Be. Macromolecular Revs. 8, pages 1 17 to 253 (1974). Of the compounds described there, comb polymers of the formula IV are particularly suitable

wherein

D is R ¹⁷ , COOR ¹⁷ , OCOR ¹⁷ , R ¹⁸ , OCOR ¹⁷ or OR ¹⁷ , E is H, CH ₃ , D or R ¹⁸ ,

G is H or D,

J is H, R ¹⁸ , R ^{18 is} COOR ¹⁷ 'aryl or heterocyclyl,

K is H, COOR ¹⁸ , OCOR ¹⁸ , OR ¹⁸ or COOH,

L is H, R ¹⁸ COOR ¹⁸ , OCOR ¹⁸ , COOH or aryl, where

R ^{17 is} a hydrocarbon radical having at least 10 carbon atoms, preferably with 10 to 30 carbon atoms,

R ^{18 is} a hydrocarbon radical having at least one carbon atom, preferably having 1 to 30 carbon atoms, m is a mole fraction in the range of 1, 0 to 0.4 and n stands for a mole fraction in the range of 0 to 0.6. Preferred comb polymers of component (a2) are, for example, by the copolymerization of maleic anhydride or fumaric acid with another ethylenically unsaturated monomer, for example with an α-olefin or an unsaturated ester, such as vinyl acetate, and subsequent esterification of the anhydride or acid function an alcohol having at least 10 carbon atoms. Further preferred comb polymers are copolymers of α-olefins and esterified comonomers, for example esterified copolymers of styrene and maleic anhydride or esterified copolymers of styrene and fumaric acid. Also mixtures of comb polymers are suitable. Comb polymers may also be polyfumarates or polymaleinates. In addition, homopolymers and copolymers of vinyl ethers are suitable comb polymers.

Polyoxyalkylenes suitable as component of class (a3) are, for example, polyalkylene esters, ethers, esters / ethers and mixtures thereof. The polyoxyalkylene compounds preferably contain at least one, particularly preferably at least two, linear alkyl groups each having from 10 to 30 carbon atoms and a polyoxyalkylene group having a molecular weight of up to 5,000. The alkyl group of the polyoxyalkylene radical preferably contains from 1 to 4 carbon atoms. Such polyoxyalkylene compounds are described, for example, in EP-A 061 895 and in US Pat. No. 4,491,455, to which reference is hereby fully made. Preferred polyoxyalkylene esters, ethers and esters / ethers have the general formula V

R ¹⁹ fO- (CH ₂ ) _y ! ΧO-R ²⁰ (V)

wherein

R ¹⁹ and R ^{20 are} each independently R ²¹ , R ²¹ OO-, R ²¹ -O-CO (CH ₂ ) _Z - or

R ^{21 is} -O-CO (CH ₂ ) _Z -CO-, where R ^{21 is} linear C 1 -C 8 -alkyl, y is a number from 1 to 4, x is a number from 2 to 200, and z is a number from 1 to 4.

Preferred polyoxyalkylene compounds of the formula V in which both R ¹⁹ and R ^{20 are} R ²¹ are polyethylene glycols and polypropylene glycols having a number average molecular weight of 100 to 5,000. Preferred polyoxyalkylenes of the formula V in which one of the radicals R ^{19 is} R ²¹ and the other is R ²¹ -CO- are polyoxyalkylene esters of fatty acids having 10 to 30 carbon atoms such as stearic acid or behenic acid. Preferred polyoxyalkylene compounds in which both R ¹⁹ and R ^{20 are} a radical R ²¹ -CO- are diesters of fatty acids having 10 to 30 carbon atoms, preferably stearic or behenic acid. Polar nitrogen compounds suitable as a component of class (a4) may be of both ionic and nonionic nature, and preferably have at least one, especially at least 2, tertiary nitrogen substituent of the general formula> NR ²² , wherein R ^{22 is} a C 8 to C 40 Hydrocarbon residue. The nitrogen substituents may also be quaternized, that is in cationic form. Examples of such nitrogen compounds are ammonium salts and / or amides obtainable by reacting at least one amine substituted with at least one hydrocarbyl radical with a carboxylic acid having 1 to 4 carboxyl groups or with a suitable derivative thereof. Preferably, the amines contain at least one linear Cs to C4o-alkyl radical. Examples of suitable primary amines for the preparation of said polar nitrogen compounds are octylamine, nonylamine, decylamine, undecylamine, dodecylamine, tetradecylamine and the higher linear homologues, secondary amines suitable for this purpose are, for example, dioctadecylamine and methylbehenylamine. Also suitable for this purpose are amine mixtures, in particular industrially available amine mixtures such as fatty amines or hydrogenated tallamines, as described, for example, in Ullmann's Encyclopedia of Industrial Chemistry, 6th edition, in the chapter "Amines, aliphatic". Suitable acids for the reaction are, for example, cyclohexane-1, 2-dicarboxylic acid, cyclohexene-1, 2-dicarboxylic acid, cyclopentane-1, 2-dicarboxylic acid, naphthalenedicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid and succinic acids substituted by long-chain hydrocarbon radicals.

Further examples of suitable polar nitrogen compounds are ring systems bearing at least two substituents of the formula -A'-NR ²³ R ²⁴ , wherein A 'represents a linear or branched aliphatic hydrocarbon group optionally substituted by one or more moieties selected from O , S, NR ³⁵ and CO, is interrupted, and R ²³ and R ^{24 are} a C 9 to C 40 hydrocarbon residue, optionally interrupted by one or more moieties selected from O, S, NR ³⁵ and CO, and or substituted by one or more substituents selected from OH, SH and NR ³⁵ R ³⁶ , wherein R ^{35 is} C 1 to C 40 alkyl optionally substituted by one or more moieties selected from CO, NR ³⁵ , O and S, interrupted, and / or by one or more radicals which are selected from NR ³⁷ R ³⁸ , OR ³⁷ , SR ³⁷ , COR ³⁷ , COOR ³⁷ , CONR ³⁷ R ³⁸ , aryl or heterocyclyl, substituted, in which R ³⁷ and R ^{38 are} each independently selected from H or C 1 to C 4 alkyl and wherein R ^{36 is} H or R ³⁵ .

In particular, the component of class (a4) is an oil-soluble reaction product of at least one tertiary amino group-containing poly (C 2 - to C 20 -carboxylic acids) with primary or secondary amines. The poly (C 2 - to C 20 -carboxylic acids) which have at least one tertiary amino group and are based on this reaction product preferably contain at least 3 carboxyl groups, in particular 3 to 12, especially 3 to 5, carboxyl groups. The carboxylic acid units in the poly Carboxylic acids preferably have 2 to 10 carbon atoms, in particular they are acetic acid units. The carboxylic acid units are suitably linked to the polycarboxylic acids, for example via one or more carbon and / or nitrogen atoms. Preferably, they are attached to tertiary nitrogen atoms, which in the case of several nitrogen atoms are linked via hydrocarbon chains.

The component of class (a4) is preferably an oil-soluble reaction product based on poly (C 2 - to C 20 -carboxylic acids) of general formula IIa or IIb having at least one tertiary amino group

HOOC _n _ X00H BB

HOOC._, N.. , NL XOOH

^BAB (IIa)

HOOC ^{'B "} I \ T ^B" COOH

I

^ COOH _{(| | b)}

in which the variable A is a straight-chain or branched C2 to Cβ-alkylene group or the grouping of the formula III

Hooc- ^B y ^{ChVCH2 '}

CH ₂ -CH ₂ -

and the variable B denotes a C 1 to C 1 alkylene group.

Furthermore, the preferred oil-soluble reaction product of component (a4), in particular that of general formula IIa or IIb, is an amide, an amide ammonium salt or an ammonium salt in which no, one or more carboxylic acid groups are converted into amide groups.

Straight-chain or branched C 2 - to C 6 -alkylene groups of the variable A are, for example, 1, 1-ethylene, 1, 2-propylene, 1, 3-propylene, 1, 2-butylene, 1, 3-butylene, 1, 4-butylene ethylene, 2-methyl-1, 3-propylene, 1, 5-pentylene, 2-methyl-1,4-butylene, 2,2-dimethyl-1,3-propylene, 1,6-hexylene (hexamethylene) and especially 1, 2-ethylene. The variable A preferably comprises 2 to 4, in particular 2 or 3, carbon atoms.

C 1 - to C 18 -alkylene groups of the variables B are before, for example, 1, 2-ethylene, 1, 3-propylene, 1, 4-butylene, hexamethylene, octamethylene, decamethylene, dodecamethylene, tetradecamethylene, hexadecamethylene, octadecamethylene, nonadecane methylene and especially methylene. Preferably, the variable B comprises 1 to 10, in particular 1 to 4, carbon atoms.

The primary and secondary amines as reaction partners for the polycarboxylic acids to form component (a4) are usually monoamines, in particular aliphatic monoamines. These primary and secondary amines may be selected from a variety of amines bearing hydrocarbon radicals, optionally linked together.

These amines, which are the oil-soluble reaction products of component (a4), are preferably secondary amines and have the general formula HNR 2 in which the two variables R independently of one another are straight-chain or branched C 10 - to C 30 -alkyl radicals, in particular C 14- to C 24 -alkyl radicals , These longer-chain alkyl radicals are preferably straight-chain or only slightly branched. As a rule, the abovementioned secondary amines are derived with regard to their longer-chain alkyl radicals from naturally occurring fatty acid or from its derivatives. Preferably, the two radicals R are the same.

The abovementioned secondary amines can be bound to the polycarboxylic acids by means of amide structures or in the form of the ammonium salts, and only one part can be present as amide structures and another part as ammonium salts. Preferably, only a few or no free acid groups are present. In a preferred embodiment, the oil-soluble reaction products of component (a4) are completely in the form of the amide structures.

Typical examples of such components (a4) are reaction products of nitrilotriacetic acid, ethylenediaminetetraacetic acid or propylene-1,2-diaminetetraacetic acid with in each case 0.5 to 1.5 mol per carboxyl group, in particular 0.8 to 1.2 mol per carboxyl group, dioleylamine, dipalmitinamine, dicoco fatty amine, distearylamine, dibehenylamine or especially ditallow fatty amine. A particularly preferred component (a4) is the reaction product of 1 mole of ethylenediaminetetraacetic acid and 4 moles of hydrogenated ditallow fatty amine.

Further typical examples of component (a4) are the N, N-dialkylammonium salts of 2-N ', N'-dialkylamidobenzoates, for example the reaction product of 1 mol of phthalic anhydride and 2 mol of ditallow fatty amine, the latter being hydrogenated or unhydrogenated , and the reaction product of 1 mole of an alkenyl spiro-bis-lactone with 2 moles of a dialkylamine, for example, ditallow fatty amine and / or tallow fatty amine, the latter two of which may be hydrogenated or unhydrogenated.

Further typical structural types for the component of class (a4) are cyclic compounds having tertiary amino groups or long-chain primary or condensates secondary amines with carboxylic acid-containing polymers, as described in WO 93/181 15.

Suitable sulfocarboxylic acids / sulfonic acids or derivatives thereof as component of class (a5) are, for example, those of the general formula VI

wherein Y 'is SO ₃ - (NR ²⁵ ₃ R ²⁶ ) ⁺ , SO ₃ - (NHR ²⁵ ₂ R ²⁶ ) ⁺ , SO ₃ - (NH ₂ R ²⁵ R ²⁶ ), SO ₃ - (NH ₃ R ²⁶ ) or

SO ₂ NR ²⁵ R ²⁶ ,

X 'for Y', CONR ²⁵ R ²⁷ , CO ₂ - (NR ²⁵ ₃ R ²⁷ ) ⁺ , CO ₂ - (NHR ²⁵ ₂ R ²⁷ ) ⁺ , R ²⁸ -COOR ²⁷ , NR ²⁵ COR ²⁷ ,

R ²⁸ OR ²⁷ , R ²⁸ OCOR ²⁷ , R ²⁸ R ²⁷ , N (CO R ²⁵ ) R ²⁷ or Z- (NR ²⁵ ₃ R ²⁷ ) ⁺ , where R ^{25 is} a hydrocarbon radical,

R ²⁶ and R ^{27 are} alkyl, alkoxyalkyl or polyalkoxyalkyl having at least 10 carbon atoms in the main chain,

R ^{28 is} C ₂ -C ₅ -alkylene,

Z- is an anion equivalent and A "and B 'are alkyl, alkenyl or two substituted hydrocarbon radicals or together with the carbon atoms to which they are attached form an aromatic or cycloaliphatic ring system.

Such sulfocarboxylic acids or sulfonic acids and their derivatives are described in EP-A-0 261 957, to which reference is hereby made in its entirety.

Poly (meth) acrylic esters suitable as component of class (a6) are both homo- and copolymers of acrylic and methacrylic acid esters. Preference is given to copolymers of at least two mutually different (meth) acrylic esters which differ with respect to the fused-in alcohol. Optionally, the copolymer contains a further, different of which olefinically unsaturated monomer copolymerized. The weight-average molecular weight of the polymer is preferably 50,000 to 500,000. A particularly preferred polymer is a copolymer of methacrylic acid and methacrylic acid esters of saturated C ₄ and C 15 alcohols, wherein the acid groups are neutralized with hydrogenated tallamine. Suitable poly (meth) acrylic esters are described, for example, in WO 00/44857, to which reference is hereby fully made. The amine component (b) is a mono- or polyamine having at least one primary or secondary amino function and thus has at least one NH bond. The NH bond and, furthermore, the basicity of component (b) caused by the lone pair of electrons optionally present on the nitrogen atom are responsible for the interaction with the cold flow improver component (a), which is effective for lowering the CFPP value when using the mixture according to the invention results in biofuel oils.

If the radicals R ¹ and R ^{2 are} pure hydrocarbyl radicals having from 4 to 40 carbon atoms, they are to be understood here as virtually pure hydrocarbon radicals of any structure but, to the extent that this does not distorts the predominant hydrocarbon character, to a minor extent heteroatoms, for example O or N. , and / or may have functional groups with heteroatoms, for example OH groups. In addition, further amino functions are allowed for the radical R ¹ , which can give this radical a stronger nitrogen-basic character. The said hydrocarbyl radicals may be saturated, unsaturated or aromatic in nature; they can be linear, branched or cyclic.

Preferably, such a hydrocarbyl radical having 4 to 40 carbon atoms denotes a linear or branched alkyl or alkenyl radical such as n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, heptyl, octyl, 2-ethylhexyl , Neo-octyl, nonyl, neononyl, decyl, neodecyl, 2-propylheptyl, undecyl, neoundecyl, dodecyl, tridecyl, isotridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl (stearyl), oleyl, linolyl, linolenyl, nonadecyl, eicosyl, hencosyl, Docosyl, tricosyl, tetracosyl, pentacosyl, hexacosyl, heptacosyl, octacosyl, nonacosyl, squalyl or their constitutional isomers. Such longer-chain alkyl radicals can also be derived from naturally occurring sources, in particular from glycerides or the underlying fatty acids.

Furthermore, such a hydrocarbyl radical having 4 to 40 carbon atoms may also denote an aryl, alkaryl or arylalkyl radical, for example phenyl, naphthyl, benzyl, 2-phenylethyl, 3-phenylpropyl, 4-phenylbutyl, o-, m- or p-tolyl or o-, m- or p-xylyl.

If the two radicals R ¹ and R ² together form a 5- to 7-membered ring, as component (b) are, for example, saturated or unsaturated secondary cyclic amines, such as corresponding alkyl- or alkenyl-substituted pyrrolidines, for example 2- or 3-dodecylpyrrolidine, 2-pyrrolines, 3-pyrrolines, pyrroles, piperidines, pyrazanes, morpholines, 1 H-azepines, indoles or isoindolines with the respective prescribed total number of carbon atoms. If the radical R ^{1 contains} further primary and / or secondary and / or tertiary amino functions, the polyamine component (b) having the respective prescribed total number of carbon atoms is, for example, N-dodecyl-1,4-butylenediamine, N ₁ N ' Bisdecylethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, dipropylenetriamine, tripropylenetetramine, tetrapropylenepentamine, pentapropylenhexamine, N, N'-bis (3-aminopropyl) ethylenediamine, 3- (N, N-dimethylamino) -propylamine (" DMAPA "), bis [3- (N, N-dimethylamino) propyl] amine (" bis-DMAPA ") or N-tallow fat 1, 3-diaminopropane.

Preferably, the hydrocarbyl radicals R ¹ and R ² each contain 6 to 30, in particular 8 to 24, especially 10 to 22 carbon atoms.

The amines of component (b) are preferably aliphatic amines, in particular aliphatic monoamines. These amines preferably have no cyclic structure.

In a preferred embodiment, the mixture according to the invention contains as monoamine component (b) at least one mono-Cio to C22-alkyl- or -alkenylamine or a di-Cio to C22-alkyl- or -alkenylamine. In the latter dialkyl or alkenylamines both chains may be different or the same. Very particular preference is given to mono-Cio- to Ci2-alkylamines.

Typical examples of such preferred mono-Cio to C22-alkyl or alkenylamines or mono-Cio to C12-alkylamines whose alkyl or alkenyl chain can be branched or preferably linear are decylamine, neodecylamine, 2-propylheptylamine , Undecylamine, neoundecylamine, dodecylamine, tridecylamine, isotridecylamine, tetradecylamine, pentadecylamine, hexadecylamine, heptadecylamine, octadecyl (stearyl) amine, oleylamine, linolylamine, linolenylamine, nonadecylamine, eicosylamine, hencosylamine and docosylamine.

Typical examples of such preferred di-Cio to C22-alkyl or alkenylamines whose alkyl or alkenyl chains may be branched or preferably linear are didecylamine, didodecylamine, ditetradecylamine, dihexadecylamine, dioctadecyl (distearyl) amine, dioleylamine, dicoco fatty amine , Ditalgfettamine, Dibehenylamine and Methylbehenylamine.

The mixture according to the invention can be prepared by simple mixing, optionally in a suitable solvent, of the two components (a) and (b) without heat input.

The mixture according to the invention is suitable as an additive to fuels, especially to biofuel oils or to mixtures of biofuel oils and middle distillate fuels of fossil origin. Its addition is especially for improvement the cold flow behavior of the fuels. Middle distillate fuels of fossil origin, which find particular use as gas oils, kerosene, diesel oils (diesel fuels) or light fuel oils, are often referred to as fuel oils. Such middle distillate fuels generally have boiling temperatures of 120 to 450 ⁰ C.

The mixture according to the invention can be injected directly into the fuels, i. undiluted, but preferably as 10 to 90 wt .-%, in particular as 25 to 80 wt .-%, especially as 45 to 75 wt .-% solution (concentrate) in a suitable solvent, usually a hydrocarbon Solvents are added. Such a concentrate containing 10 to 90 wt .-%, in particular 25 to 80 wt .-%, especially 45 to 75 wt .-%, based on the total amount of the concentrate, the mixture according to the invention, dissolved in a hydrocarbon solvent, is therefore also the subject of the present invention. Common solvents in this context are aliphatic or aromatic hydrocarbons, for example xylenes or mixtures of high-boiling aromatics such as solvent naphtha. Also naphthalene aromatic hydrocarbon mixtures such as naphthalene poor solvent naphtha can be used advantageously as a solvent here. Also suitable for this purpose are solvents which are soluble in biofuel oils and middle distillates and from the group of alcohols, esters and ethers, including the polyoxyalkylenes and the polyglycols. Even middle distillate fuels themselves can be used as solvents for such concentrates.

The metering rate of the mixture in the fuels is generally 10 to 10,000 ppm by weight, in particular 50 to 5000 ppm by weight, especially 100 to

3000 ppm by weight, e.g. 500 to 1500 ppm by weight, in each case based on the total amount of fuel.

The mixture of components (a) and (b) can be added to the fuels as a prefabricated mixture, in particular in the form of the concentrate described above. However, it is also possible to add the components (a) and (b) individually to the fuels so that the mixture according to the invention is physically present only in the fuel.

In a preferred embodiment, the mixture according to the invention is used as an additive to fuels which

(A) to 0.1 to 100 wt .-%, preferably to 0.1 to less than 100 wt .-%, in particular to 10 to 95 wt .-%, especially to 30 to 90 wt .-%, of at least one biofuel based on fatty acid esters, and

(B) to 0 to 99.9 wt .-%, preferably to more than 0 to 99.9 wt .-%, in particular to 5 to 90 wt .-%, especially to 10 to 70 wt .-%, of Middle distillates of fossil origin and / or of vegetable and / or animal origin, which are essentially hydrocarbon mixtures and are free of fatty acid esters,

consist.

In a particularly preferred embodiment, the mixture according to the invention is used as an additive to fuels which consist of at least 100% by weight of at least one biofuel oil (A) based on fatty acid esters.

The fuel component (A) is usually referred to as "biodiesel". The middle distillates of the fuel component (A) are preferably substantially alkyl esters of fatty acids derived from vegetable and / or animal oils and / or fats. Alkyl esters are usually lower alkyl esters, in particular C 1 to C 4 alkyl esters, understood by transesterification of occurring in vegetable and / or animal oils and / or fats glycerides, especially triglycerides, by means of lower alcohols, such as ethanol, n-propanol, iso-Pro - Panol, n-butanol, iso-butanol, sec-butanol, tert-butanol or especially methanol ("FAME") are available.

Examples of vegetable oils which are converted into corresponding alkyl esters and thus can serve as a basis for biodiesel are castor oil, olive oil, peanut oil, pear kernel oil, coconut oil, mustard oil, cottonseed oil, and in particular sunflower oil, palm oil, soybean oil and rapeseed oil. Other examples include oils that can be extracted from wheat, jute, sesame and the shea nut; furthermore, arachis oil, jatropha oil and linseed oil are also usable. The recovery of these oils and their conversion to the alkyl esters are known in the art or may be derived therefrom.

It is also possible to convert already used vegetable oils, for example used frying oil, if appropriate after appropriate purification, into alkyl esters and thus serve as the basis for biodiesel.

Vegetable fats are also useful in principle as a source of biodiesel, but play a minor role.

Examples of animal fats and oils that are converted to corresponding alkyl esters and thus can serve as the basis for biodiesel include fish oil, beef tallow, swine tallow, and similar fats and oils derived from the slaughtering or recycling of farmed or wild animals. As the said vegetable and / or animal oils and / or fats underlying saturated or unsaturated fatty acids, which usually have 12 to 22 carbon atoms and may carry additional functional group such as hydroxyl groups, occur in the alkyl esters in particular lauric acid, myristic acid, palmitic acid, stearic acid, Oleic acid, linoleic acid, linolenic acid, elaidic acid, erucic acid and / or ricinoleic acid.

Typical lower alkyl esters based on vegetable and / or animal oils and / or fats which are used as biodiesel or biodiesel components are, for example, sunflower methyl ester, palm oil methyl ester ("PME"), soybean oil methyl ester ("SME") and especially rapeseed oil methyl ester ("RME"). ).

However, it is also possible to use the monoglycerides, diglycerides and especially triglycerides themselves, for example castor oil, or mixtures of such glycerides as biodiesel or components for biodiesel.

For the purposes of the present invention, fuel component (B) is to be understood as meaning middle distillate fuels boiling in the range from 120 to 450 ^° C. Such middle distillate fuels are used in particular as diesel fuel, heating oil or kerosene, with diesel fuel and heating oil being particularly preferred.

Middle distillate fuels are fuels which are obtained by distillation of crude oil as a first process step and boil in the range of 120 to 450 ⁰ C. Preferably, low-sulfur middle distillates are used, ie those containing less than 350 ppm sulfur, especially less than 200 ppm sulfur, especially less than 50 ppm sulfur. In special cases they contain less than 10 ppm sulfur, these middle distillates are also called "sulfur-free". These are generally crude oil distillates, which have been subjected to a hydrogenating refining, and therefore contain only small amounts of polyaromatic and polar compounds. Preferably those middle distillates which have 90% distillation points below 370 ⁰ C, in particular below 360 ° C and in special cases below 330 ° C.

Low-sulfur and sulfur-free middle distillates can also be obtained from heavier petroleum fractions, which can no longer be distilled under atmospheric pressure. Hydrocarbon cracking, thermal cracking, catalytic cracking, coker processes and / or visbreaking may be mentioned as typical conversion processes for the preparation of middle distillates from heavy petroleum fractions. Depending on how the process is carried out, these middle distillates are produced with little or no sulfur or are subjected to hydrogenating refining. The middle distillates preferably have aromatics contents of less than 28% by weight, in particular less than 20% by weight. The content of normal paraffins is between 5% and 50% by weight, preferably between 10 and 35% by weight.

Among the middle distillates referred to as fuel component (B), middle distillates should also be understood here, which can be derived either indirectly from fossil sources such as crude oil or natural gas or else produced from biomass via gasification and subsequent hydrogenation. A typical example of a middle distillate fuel derived indirectly from fossil sources is GTL (gas-to-liquid) diesel fuel produced by Fischer-Tropsch synthesis. From biomass, for example, a middle distillate is produced via the BTL ("biomass-to-liquid") process, which can be used either alone or in admixture with other middle distillates as fuel component (B). The middle distillates also include hydrocarbons obtained by hydrogenation of fats and fatty oils. They mainly contain n-paraffins. The said middle distillate fuels have in common that they are essentially hydrocarbon mixtures and are free from fatty acid esters.

The qualities of fuel oils and diesel fuels are specified in greater detail in, for example, DIN 51603 and EN 590 (see also Ullmann's Encyclopedia of Industrial Chemistry, 5th Edition, Volume A12, pp. 617 et seq., To which reference is expressly made).

The mixture according to the invention can be added both in pure biofuel oils (biodiesel) and in their mixtures with the stated middle distillate fuels in order to improve their properties. In both cases, a significant improvement in the cold flow behavior of the fuel, i. a reduction in particular the CFPP values, but also the CP values and / or the PP values, regardless of the origin or composition of the fuel observed. The precipitated crystals are usually kept effectively in suspension, so that it does not come to blockages of filters and pipes by such sediments. The mixture of the invention has a good broad effect in most cases and thus causes the precipitated crystals are very well dispersed in a variety of fuels.

Likewise, by using the mixture according to the invention a number of other fuel properties can be improved. By way of example, only the additional effect of protecting against corrosion or improving the oxidation stability should be mentioned here. The present invention also relates to fuels from or containing biofuel oils (biodiesel) which contain the mixture according to the invention, in particular in the above-mentioned metering rates. In general, the fuels mentioned or the fuel additive concentrates mentioned contain further cold flow improvers (as described above) as further additives in amounts customary therefor, paraffin dispersants, conductivity improvers, anti-corrosion additives, lubricity additives, antioxidants, metal deactivators, anti-oxidants. foaming agents, demulsifiers, detergents, cetane improvers, solvents or diluents, dyes or fragrances or mixtures thereof. The abovementioned further additives, which have not yet been mentioned above, are familiar to the person skilled in the art and therefore need not be further explained here.

The following examples are intended to illustrate the present invention without limiting it.

Examples

Used fuels:

To compare the effectiveness of the inventive mixture in diesel fuel of fossil origin, a typical German winter diesel fuel was used with the following properties:

CP (DIN EN 23015): -6.5 ° C

CFPP (DIN EN 1 16) -9 ° C

Density at 15 ° C (EN ISO 1285): 835.6 kg / m ³

Cetane index: (ASTM D 4737) 51, 8

Boiling gradient (EN ISO 3405):

Initial boiling point: 185 ° C

5% by volume to: 202 ^° C.

10% by volume to 210 ^° C.

50% by volume to 265 ° C

90% by volume to 330 ^° C.

95% by volume to 342 ° C

Boiling 353 ° C n paraffin content (GC method): 21, 4 wt .-%

For the examples given here, the following biofuel oils (FAME) were used:

Used additives:

The additives used can be characterized as follows:

EVA-1: Ethylene-vinyl acetate copolymer prepared according to WO 9/27,748, vinyl acetate content 30 wt .-%, viscosity at 120 ⁰ C: 70 cSt (the indicated

Dosage amounts refer to the pure copolymer)

EVA-1-SN: Solution of 60% by weight of EVA-1 in 40% by weight of solvent naphtha

EVA-2: analog EVA-1, but with a vinyl acetate content of 35 wt .-%

Amines: according to the chemical definition; available in the chemical trade; as coconut fatty amine Armeen C of the company AkzoNobel was used; Noric 2C from Ceca, France, was used as the nicotine fatty amine (coconut fatty and dicoco fatty amines mainly contain dodecyl and tetradecyl radicals as alkyl groups)

WASA commercial WASA from BASF, available under the name Kero-flux 3614

EA 1: Inventive mixture of 40% by weight of EVA-1, 30% by weight of dodecylamine and 30% by weight of solvent naphtha EA 2: Inventive mixture of 35% by weight of EVA-2, 30% by weight of dodecylamine and 35% by weight of solvent naphtha

The Solvent Naptha used was Solvesso® 150 from Exxon.

Comparative Example 1 in diesel fuel of fossil origin

The table below shows that the effect of the inventive mixture of component (a) (cold flow improver MDFI, optionally in combination with WA-SA) with the amine component (b) from use in pure fossil diesel fuel was unpredictable.

Note: for ease of handling, EVA-1 was diluted with 40 weight percent solvent naphtha.

Inventive Example 2 in Biofuel Oil (06/222)

The results show that the use of an EVA / amine mixture can drastically reduce the feed rates of cold flow improvers (MDFI). Inventive Example 3 - Variation of amines

The experiments shown below demonstrate that the CFPP enhancing effect of the amine is not limited to dodecylamine as contained in EA 1 and EA 2.

Inventive Example 4 - Ratio of cold flow improver to amine

The values below show that the ratio of cold flow improver (a) to amine (b) can be varied over a wide range.

Inventive example 5 - Improvement of the cold properties of mixtures of different biofuel oils

According to the following results, mixtures of RME with other biofuel oils (FAME) in the cold properties can also be improved.

Inventive Example 6 - Use of Secondary Amines

As the following data show, the CFPP-improving effect of the amine component (b) is not limited to primary amines.

Claims

claims

1. mixture containing

(A) 5 to 95 wt .-% of at least one organic compound which in the

Able to improve the cold flow behavior of fuels, and

(B) 5 to 95 wt .-% of at least one amine of the general formula I.

R ¹ R ² HN (I)

in which R ^{1 is} a hydrocarbyl radical having 4 to 40 carbon atoms, which may contain even more primary and / or secondary and / or tertiary amino functions, and R ² denotes a hydrocarbyl radical having 4 to 40 carbon atoms or hydrogen, where R ¹ and R ² together can also form a 5- to 7-membered ring,

the sum of components (a) and (b) being 100% by weight.

2. Mixture according to claim 1, comprising as component (a) at least one organic compound selected from

(a1) copolymers of a C2 to C4o olefin with at least one further ethylenically unsaturated monomer; (a2) comb polymers;

(a3) polyoxyalkylenes;

(a4) polar nitrogen compounds;

(a5) sulfocarboxylic acids or sulfonic acids or their derivatives; and

(a6) poly (meth) acrylic esters.

3. Mixture according to claim 2, comprising as component (a1) at least one ethylene-vinyl acetate copolymer.

4. Mixture according to claim 3, comprising as component (a1) at least one terpolymer of a C2 to C4o-α-olefin, a d- to C2o-alkyl ester of an ethylenically unsaturated monocarboxylic acid having 3 to 15 carbon atoms and a C2 - to Ci4-alkenyl ester of a saturated monocarboxylic acid having 2 to 21 carbon atoms.

5. Mixture according to claims 1 to 4, comprising as component (b) at least one mono-Cio to C22-alkyl or -alkenylamin or a di-Cio to C22-alkyl or -alkenylamine.

6. Use of the mixture according to claims 1 to 5 as an additive to fuels.

7. Use of the mixture according to claim 6 as an additive to fuels, which

(A) from 0.1 to 100% by weight of at least one biofuel based on fatty acid esters, and

(B) to 0 to 99.9 wt .-% of middle distillates of fossil origin and / or of vegetable and / or animal origin, which are substantially hydrocarbon mixtures and are free of fatty acid esters exist.

Use according to claim 7, wherein the fuel component (A) is essentially alkyl esters of fatty acids derived from vegetable and / or animal oils and / or fats.

9. fuels according to claim 6 to 8, comprising a mixture according to claims 1 to 5.

10. A fuel according to claim 9, containing as further additives in customary amounts further Kaltfließverbesserer, paraffin dispersants, conductivity, corrosion protection additives, lubricity additives, antioxidants, metal deactivators, anti-foaming agents, demulsifiers, detergents, cetane improvers, solvents or diluents , Dyes or fragrances or mixtures thereof.

1 1. A fuel additive concentrate containing 10 to 90 wt .-%, based on the total amount of the concentrate, of a mixture according to claims 1 to 5, dissolved in a hydrocarbon solvent.

12. Fuel additive concentrate according to claim 11, comprising as further additives in customary amounts thereof further cold flow improvers, paraffin dispersants, conductivity improvers, corrosion protection additives, lubricity additives, antioxidants, metal deactivators, antifoams, demulsifiers, detergents, cetane number improvers, solvents or diluents, dyes or fragrances or mixtures thereof.