Patent Application
20070214713
The present invention relates to the use of polyamines having at least one terminal secondary or tertiary amine function as a detergent additive for fuels and lubricants; to additive concentrates comprising such polyamines; to fuels and lubricants additized with these polyamines and to processes for their preparation.
During the operation of combustion engines, there nay be formation of undesired deposits in the region of the combustion chamber and of the fuel intake system in the case of diesel fuels, carbon deposits are to be observed in the region of the injection nozzles and holes and can impair the optimal formation of a finely divided fuel mist in direction-injection high-performance systems such as common rail, pump-nozzle or pump-line-nozzle and thus lead to increased fuel consumption and emissions. In order to minimize or entirely prevent the disruptions associated with the occurrence of such deposits detergent additives are added to the fuels.
Examples of such detergent additives include in particular polyalkenylsuccinimides. These find manifold use in fuels and lubricants, typically in combination with other additives; cf., for example, EP-A-0264247, EP-A-0271937 and WO-A-98/42808.
For instance, WO-A-98/42808 describes the use of specific reaction products of a polyalkenyl derivative of a monoethylenically unsaturated C4-C10-dicarboxylic acid with a polyamine having terminal primary amine groups as a detergent additive for low-sulfur diesel fuels.
DE-A-101 23 553 discloses a process for preparing polyalkenylsuccinimides in which PIBSA is, for example, reacted with an oligo- or polyamine in the presence of an alcohol. The oligo- or polyamines used likewise have terminal primary amine groups.
WO 2004/024851 describes synergistically active additive mixtures for lubricants and fuels composed of an additive having detergent action and a partly or fully neutralized fatty acid. The detergent additives specified include compounds having a hydrophobic hydrocarbon radical having an Mn of from 85 to 20 000 whose polar end group is selected from moieties derived from carboxylic anhydrides and having hydroxyl and/or amino and/or amido groups. Dicarboximides of polyalkylene polyamines having terminal secondary or tertiary amine end groups in the end product were not investigated therein.
A disadvantage of the additives and the additive mixtures described in the prior art is that relatively high dosages are required to achieve a cleaning or keep-clean effect.
It is therefore an object of the present invention to provide improved detergent additives for fuel and lubricant compositions, especially diesel fuels, which are effective even at low dosages and especially effectively reduce nozzle carbonization.
It has been found that, surprisingly, the above object is achieved by providing linear polyamines having at least one terminal secondary or tertiary amine function as a detergent additive for fuels and lubricants.
The invention firstly provides the use of a compound of the general formula I
R1R2N((CH2)xNHy(CH2)zNR3R4 (I)
where
A “reduction of the carbonization of the nozzles” is understood to be a partial or complete reduction of the degree of the carbonization of the nozzles in comparison with the degree of carbonization occurring with a fuel without additives (i.e. in the absence of a compound of formula I in the fuel), as determined in a standardized test engine, in particular in accordance with the standardized test engine employed for the determination of air flow restriction described below.
A first preferred group of compounds comprises compounds of the following general formula II
where x, y, z, R, R3 and R4 are each as defined above. Such compounds are thus terminated by a secondary or tertiary amine function. Especially mentioned are compounds of formula II where R3 and R4 are the same or different and are a C1-C10-, C1-C8-, C1-C6-, C1-C5- or C1-C4-alkyl group.
Embodiments of polyalkenyl radicals R which are preferred in accordance with the invention are illustrated later in section C2). Especially preferably, R is a polyisobutenyl radical. The polyisobutenyl radical has in particular an Mn of from about 500 to 1000.
A second preferred group of compounds comprises compounds of the formula I, wherein R1, R2, R3 and R4 are each independently H or C1-C10-alkyl but neither R1 and R2 nor R3 and R4 are simultaneously H, and x, y and z are each as defined above. Such compounds are thus terminated by two secondary and/or tertiary amine functions.
Preference is given in particular to those compounds of the formula I and II, wherein x and z are each independently an integer from 2, 3 or 4 and y is 1, 2 or 3.
Particular preference is further given to those compounds of the formula I and II wherein R3 and R4 are each independently H or C1-C8-, C1-C6-, C1-C5 or C1-C4-alkyl but R3 and R4 may not simultaneously each be H; or wherein R3 and R4 are simultaneously C1-C8-, C1-C6-, C1-C5 or C1-C4-alkyl, Preferably R3 and R4 have the same meaning.
Particular preference is also given to compounds of the formula I wherein R1, R2, R3 and R4 are simultaneously each C1-C4-alkyl.
In another preferred embodiment, the reaction products or mixtures, partly purified if appropriate, obtained in the preparation of compounds of the formula I are used.
It is possible in accordance with the invention to use, for example, a reaction product comprising an imide compound of the formula I, for example a compound of the formula II, the reaction product being obtainable by reacting a cyclic C4-C6-dicarboxylic anhydride which is substituted by at least one polyalkenyl radical R which has a number-average molecular weight Mn of from 100 to 2500 with a polyamine of the formula III
H2N((CH2)xNH)y(CH2)zNR3R4 (III)
where x, y, z, R3 and R4 are each as defined above, if appropriate followed by a removal of volatile constituents of the reaction mixture. The reaction can be effected according to the disclosure of DE-A-101 23 553.
The above-described detergent additives are used customarily in combination with at least one further conventional fuel or lubricant additive which will be described more precisely later.
The additive of the formula is added in an amount of about 1-200 mg/kg of fuel, more preferably in a dosage of from 1 to 100, from 1 to 50, from 1 to 30, from 2 to 20 or from 2 to 16 mg/kg of fuel.
The additive of the formula I is preferably added in an amount which brings about a maximum degree of carbonization of 80%, preferably of 70%, for example from 0 to 65%, from 2 to 50% or from 5 to 40%, determined to CEC F23 A 01 (in an XUD9 test engine at 0.1 mm needle stroke) via the percentage air flow restriction.
The invention further provides fuel compositions comprising in a majority of a hydrocarbon fuel boiling in the range from 100 to 500° C., for example from 150 to 400° C. or from 160 to 360° C., in particular a middle distillate fuel, for example diesel fuel, an effective amount of at least one detergent additive of the formula I as defined above.
The invention also provides lubricant compositions comprising in a customary lubricant, at least an effective amount of at least one detergent additive of the formula I as defined above.
The invention also relates to additive concentrates comprising at least one detergent additive of the formula I as defined above in combination with at least one further customary fuel or lubricant additive additive. The inventive additive is present in the concentrates preferably in an amount of from 0.1 to 80% by weight, more preferably from 1 to 70% by weight and in particular from 20 to 60% by weight based on the total weight of the concentrate.
The invention also provides a process for preparing a fuel composition having improved fuel intake system-cleaning action, wherein an effective amount of at least one compound as defined above or of an additive concentrate as defined above is added to a commercial fuel composition.
Finally, the invention provides a process for preparing a lubricant composition having improved cleaning action, wherein an effective amount of at least one compound as defined above or of an additive concentrate as defined above is added to a commercial lubricant composition.
In the above definition of the R1, R2, R3 and R4 radicals, C1-C10-alkyl represents in particular C1-C4-alkyl radicals such as methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, and also the longer-chain pentyl, hexyl, heptyl, octyl, nonyl and decyl radicals, and also the mono- or polybranched, for example mono-, di- or tribranched, analogs thereof.
The C4-C6-dicarboximide ring is derived in particular from monoethylenically unsaturated C4-C6-dicarboxylic acids and derivatives thereof, especially anhydrides. Suitable dicarboxylic acids are the monounsaturated forms of succinic acid, glutaric acid and adipic acid.
A1) Dicarboximide Derivatives of Group 1
These compounds are obtainable, for example, by the reaction of a dicarboxylic acid substituted by a hydrophobic hydrocarbon radical or of a dicarboxylic acid derivative substituted by a hydrophobic hydrocarbon radical with an amine which has at least one NH2 group. Preference is given to reacting a carboxylic anhydride.
The molar ratio of dicarboxylic acid (derivative) groups to hydrocarbon radical is in the range of 0.8:2, or 0.9:1.5 or 0.9:1.05, as described, for example, also in EP-A-0 355 895 and 0 587 381.
The reaction of such dicarboxylic acids or derivatives thereof, especially of dicarboxylic anhydrides, with amines may result in product mixtures which comprise dicarboxylic monoamides, dicarboxylic diamides, ammonium salts of dicarboxylic monoamides, dicarboxylic monoamide monoesters, amidines and dicarboxylic mono- and diimides. Suitable as the inventive additive are both the acylation products specified individually and mixtures thereof.
However, preference is given to dicarboximides, especially dicarboxylic monoimides and mixtures which comprise them. The imide fraction is in particular in the range from 1 to 100 mol %, for example from 10 to 95 mol % or from 30 to 90 mol %.
The coupling ratio (PIBSA/AMINE) is in the range from 0.5 to 2 based on the ratio of succinic acid groups to amine, for example from 0.8 to 1.2, more preferably from 0.9 to 1.05.
Amines suitable for the reaction with the dicarboxylic acid or the dicarboxylic acid derivative are polyamines of the above formula III.
Suitable polyamines are, for example, the mono-N,N-dialkyl derivatives of diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, dipropylenetriamine, tripropylenetetramine, tetrapropylenepentamine, pentapropylenehexamine, dibutylenetriamine, tributylenetetramine, tetrabutylenepentamine, pentabutylenehexamine.
Examples include N,N-dimethyldimethylenetriamine, N,N-diethyldimethylenetriamine, N,N-dipropyldimethylenetriamine, N,N-dimethyldiethylene-1,2-triamine, N,N-diethyldiethylene-1,2-triamine, N,N-dipropyldiethylene-1,2-triamine, N,N-dimethyldipropylene-1,3-triamine (i.e. DMAPAPA), N,N-diethyldipropylene-1,3-triamine, N,N-dipropyldipropylene-1,3-triamine, N,N-dimethyldibutylene-1,4-triamine, N,N-diethyldibutylene-1,4-triamine, N,N-dipropyldibutylene-1,4-triamine, N,N-dimethyldipentylene-1,5-triamine, N,N-diethyldipentylene-1,5-triamine, N,N-dipropyldipentylene-1,5-triamine, N,N-dimethyldihexylene-1,6-triamine, N,N-diethyldihexylene-1,6-triamine and N,N-dipropyldihexylene-1,6-triamine.
A2) Polyamines of Group 2 which are Terminated by Two Seconds and/or Tertiary Amine Functions
Nonlimiting examples include:
Linear polyamines terminated by identical N,N-dialkylamino groups, such as bis[2-(N,N-dimethylamino)ethyl]amine, bis[2-(N,N-diethylamino)ethyl]amine, bis[2-(N,N-dipropylamino)ethyl]amine, bis[3-(N,N-dimethylamino)propyl]amine, bis[3-(N,N-diethylamino)propyl]amine, bis[3-(N,N-dipropylamino)propyl]amine, bis[4-(N,N-dimethylamino)butyl]amine, bis[4-(N,N-diethylamino)butyl]amine, bis[4-(N,N-dipropylamino)butyl]amine, bis[5-(N,N-dimethylamino)pentyl]amine, bis[5-(N,N-diethylamino)pentyl]amine, bis[5-(N,N-dipropylamino)pentyl]amine, bis[6-(N,N-dimethylamino)hexyl]amine, bis[6-(N,N-diethylamino)hexyl]amine, bis[6-(N,N-dipropylamino)hexyl]amine and the corresponding analogs terminated by identical monoalkylamino groups. Also usable are corresponding polyamines which are terminated by different mono- or dialkylamino groups, and mixtures of such compounds.
Polyamines of the above type are described in Kirk-Othmer “Encyclopedia of Chemical Technology”, 2nd edition, Volume 7, pages 22 to 37, Interscience Publishers, New York (1965, “Ethylenamines” chapter).
B) Preparation of Inventive Additives
B1) Dicarboximide Additives of Group 1
Processes for preparing these compounds are known to those skilled in the art. A particularly suitable process for preparing polyalkenylsuccinimides is described in the German patent application DE-A-10123553.4, which is fully incorporated herein by reference. in this process, a polyalkenylsuccinic anhydride is reacted first with an alcohol or a phenol and subsequently with an amine. Alternatively, the polyalkenylsuccinic anhydride is reacted with the amine in the presence of an alcohol or of a phenol.
Alcohols suitable for preparing polyalkenylsuccinimides are preferably monohydric; however, polyhydric alcohols are also suitable.
Preference is given to using monohydric alcohols having from 1 to 16 carbon atoms, such as methanol, ethanol, propanol, isopropanol, butanol, sec-butanol, isobutanol, tert-butanol, 2-hydroxymethylfuran, amyl alcohol, isoamyl alcohol, vinylcarbinol, cyclohexanol, n-hexanol, 6-capryl alcohol, 2-ethylhexanol, n-decanol, lauryl alcohol, isooctyl alcohol and mixtures thereof. Preferred alcohols are those having from 6 to 16 carbon atoms. Particular preference is given to 2-ethylhexanol.
Suitable phenols include phenol, naphthol, (o,p)-alkylphenols and salicylic acid.
Processes for preparing polyalkenyl-substituted dicarboxylic acids or derivatives thereof are known, For instance, the German patent application DE-A-10123553.4 describes the preparation of a polyolefin-substituted carboxylic acid or of a derivative thereof by the reaction of a polyalkene with a monounsaturated acid or derivative thereof, in the course of which the polyalkylene adds to the double bond of the acid component in an ene reaction. Other processes are described, for example, also in WO-A-98/42808, which is incorporated herein by reference.
B2) Polyamines of Group 2 having Two Terminal Secondary or Tertiary Amine Functions
They are prepared as described in Ullmann's Encyclopedia of industrial Chemistry, 6th ed. 2000, Electronic release, Chapt 8.2, Oligo- and Polyamines.
The polyamines of the formula III are prepared in a similar manner
C) Different Applications of Inventive Polyamines
The inventive polyamine products can be used as additives (usually in the form of additive packages or concentrates) for fuels, especially diesel fuel, heating oil, kerosene, or middle distillates in genera, and gasoline fuel, or lubricants.
When the inventive polyamines are used as diesel fuel additives, they contain an effective amount of polyamine. Appropriately, the diesel fuels contain a proportion of from about 1 to 5000 ppm, or of from about 5 to 1000 ppm, for example from about 5 to 200 or from 10 to 100 ppm, based on the total weight of the diesel fuel.
The diesel fuel additive mixtures used comprise at least one further additive selected from other customary detergents, corrosion inhibitors, dehazers, demulsifiers, antifoams, antioxidants, metal deactivators, multifunctional stabilizers, cetane number improvers, combustion improvers, dyes, markers, solubilizers, antistats, lubricity improvers.
The inventive polyamines may also be used as additives for heating oil. They are used in an effective amount, appropriately in an amount of from 10 to 1000 ppm, preferably from 50 to 500 ppm, based on the total weight of the heating oil. This may comprise at least one further additive which may be selected from corrosion inhibitors, demulsifiers, antifoams, antioxidants, metal deactivators, ferrocenes and deodorants.
The inventive polyamines may also be used as additives for gasoline fuels. These contain an effective amount of inventive polyamines, appropriately from 1 to 5000 ppm, or of from about 5 to 1000 ppm, for example from about 5 to 200 or from 10 to 100 ppm, based on the total weight of the gasoline fuel.
The gasoline fuel additive mixtures may also comprise at least one further additive selected from other customary detergent additives, carrier oils, lubricity improvers, solvents and corrosion inhibitors.
Finally, the inventive polyamines are also suitable for lubricant compositions which contain an effective amount of inventive products, appropriately from 0.1 to 10% by weight, preferably from 0.5 to 5% by weight, based on the total weight of the lubricant composition.
The lubricant compositions may also comprise further additives which are in particular selected from lubricity improvers, wear protection additives, corrosion inhibitors, VI improvers.
Some additives usable as coadditives are described hereinbelow:
C1) Detergent Additives
Additives having detergent action have at least one hydrophobic hydrocarbon radical having a number-average molecular weight (Mn) of from 85 to 20 000 and at least one polar moiety selected from:
Additives containing mono- or polyamino groups (a) are preferably polyalkene monoamines or polyalkene polyamines based on polypropene or on reactive (i.e. having predominantly terminal double bonds, usually in the beta- and gamma-position) or conventional (i.e. having predominantly internal double bonds) polybutene or polyisobutene having MN= from 300 to 5000. Such additives based on reactive polyisobutene, which can be prepared from the polyisobutene which may contain up to 20% by weight of n-butene units by hydroformylation and reductive amination with ammonia, monoamines or polyamines, such as dimethylaminopropylamine, ethylenediamine, diethylenetriamine, triethylenetetramine or tetraethylenepentamine, are disclosed in particular in EP-A 244 616. When polybutene or polyisobutene having predominantly internal double bonds (usually in the beta and gamma position) are used as starting materials in the preparation of the additives, a possible preparative route is by chlorination and subsequent amination or by oxidation of the double bond with air or ozone to give the carbonyl or carboxyl compound and subsequent amination under reductive (hydrogenating) conditions. The amines used here for the amination may be the same as those used above for the reductive amination of the hydroformylated highly reactive polyisobutene. Corresponding additives based on polypropene are described in particular in WO-A 94/24231, which is fully incorporated herein by reference.
Further preferred additives containing monoamino groups (a) are the hydrogenation products of the reaction products of polyisobutenes having an average degree of polymerization P= from 5 to 100 with nitrogen oxides or mixtures of nitrogen oxides and oxygen, as described in particular in WO-A 97/03946, which is fully incorporated herein by reference.
Further preferred additives containing monoamino groups (a) are the compounds obtainable from polyisobutene epoxides by reaction with amines and subsequent dehydration and reduction of the amino alcohols, as described in particular in DE-A 196 20 262, which is fully incorporated herein by reference.
Additives containing nitro groups, optionally in combination with hydroxyl groups, (b) are preferably reaction products of polyisobutenes having an average degree of polymerization P= from 5 to 100 or from 10 to 100 with nitrogen oxides or mixtures of nitrogen oxides and oxygen as described in particular in WO-A 96/03367 and WO-A 96/03479, which are fully incorporated herein by reference, These reaction products are generally mixtures of pure nitropolyisobutenes (e.g. alpha,beta-dinitropolyisobutene) and mixed hydroxynitropolyisobutenes (e.g. alpha-nitro-beta-hydroxypolyisobutene).
Additives containing hydroxyl groups, optionally in combination with mono- or polyamino groups, (c) are in particular reaction products of polyisobutene epoxides obtainable from polyisobutene having preferably predominantly terminal double bonds and MN= from 300 to 5000 with ammonia or mono- or polyamines, as described in particular in EP-A 476 485, which is fully incorporated herein by reference.
Additives containing polyoxy-C2- to C4-alkylene moieties (d) are preferably polyethers or polyetheramines which are obtainable by reaction of C2- to C60-alkanols, C6- to C30-alkanediols, mono- or di-C2-C30-alkylamines, C1-C30-alkylcyclohexanols or C1-C30-alkylphenols with from 1 to 30 mol of ethylene oxide and/or propylene oxide and/or butylene oxide per hydroxyl group or amino group and, in the case of the polyetheramines, by subsequent reductive amination with ammonia, monoamines or polyamines. Such products are described in particular in EP-A 310 875, EP-A 356 725, EP-A 700 985 and U.S. Pat. No. 4,877,416, which are fully incorporated herein by reference. In the case of polyethers, such products also have carrier oil properties. Typical examples of these are tridecanol butoxylates, isotridecanol butoxylates, isononylphenol butoxylates and polyisobutenol butoxylates and propoxylates and also the corresponding reaction products with ammonia.
Additives containing carboxylic ester groups (e) are preferably esters of mono-, di- or tricarboxylic acids with long-chain alkanols or polyols, in particular those having a minimum viscosity of 2 mm2 at 100° C., as described in particular in DE-A 38 38 918, which is fully incorporated herein by reference. The mono-, di- or tricarboxylic acids used may be aliphatic or aromatic acids, and particularly suitable ester alcohols or ester polyols are long-chain representatives having, for example, from 6 to 24 carbon atoms. Typical representatives of the esters are adipates, phthalates, isophthalates, terephthalates and trimellitates of isooctanol, of isononanol, of isodecanol and of isotridecanol. Such products also have carrier oil properties.
Additives containing moieties conventional obtained by conventional Mannich reaction of phenolic hydroxyl groups with aldehydes and mono- or polyamines (f) are preferably reaction products of polyisobutene-substituted phenols with formaldehyde and primary mono- or polyamines such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine or dimethylaminopropylamine. The polyisobutenyl-substituted phenols may stem from conventional or highly reactive polyisobutene having Mn= from 300 to 5 000. Such “polyisobutene-Mannich bases” are described in particular in EP-A 831 141, which is fully incorporated herein by reference.
Additives containing moieties derived from carboxylic anhydrides and having hydroxyl and/or amino and/or amido and/or imido groups (g) are preferably corresponding derivatives of dicarboxylic anhydrides, more preferably of succinide anhydride. It is self-evident that the term “moieties derived from carboxylic anhydrides . . . ” does not necessarily require that the starting materials actually have to be the carboxylic anhydrides. It will be appreciated that such moieties may also be obtained by the reaction of other carboxylic acid derivatives which have the required activity, for example carbonyl halides, or else by the reaction of the carboxylic acid itself when suitable activation measures are taken. However, carboxylic anhydrides are particularly suitable derivatives for the conversion to the moieties mentioned.
The polar moiety of component A is more preferably a moiety derived from carboxylic anhydrides and having hydroxyl and/or amino and/or amido and/or imido groups (g), especially having amido and/or imido groups, i.e. N-acyl moieties.
The hydrophobic hydrocarbon radical of the above-described detergent additives (a) to (g) and the hydrophobic R radical of inventive polyamine detergents of the formulae I and II are preferably a homo- or copolymer radical whose repeating units are derived from monomers which are selected from propene, n-butene and isobutene and mixtures thereof.
The homo- or copolymer radicals is more preferably a polyisobutene radical, In particular, the homo- or copolymer radical is a radical which is derived from “reactive” polyisobutenes which differ from the “low-reactivity” polyisobutenes by the content of terminal double bonds. Reactive polyisobutenes differ from low-reactivity polyisobutenes in that they contain at least 50 mol %, preferably at least 60 mol % and more preferably at least 80 mol %, based on the total number of polyisobutene macromolecules, of terminal double bonds. The terminal double bonds may be either vinyl double bonds [—CH═C(CH3)2] or vinylidene double bonds [—CH2—C(═CH2)—CH3]. Preference is given in particular to polyisobutenes which have uniform polymer skeletons. Uniform polymer skeletons are in particular those polyisobutenes which are composed to an extent of at least 85% by weight, preferably to an extent of at least 90% by weight and more preferably to an extent of at least 95% by weight, of isobutene units. For example, such reactive polyisobutenes have a number-average molecular weight in the range from 100 to 20 000. Suitable reactive polyisobutenes for preparing fuel additives are in particular those which have a number-average molecular weight in the range from 100 to 3000, such as from 200 to 2500 or from 500 to 1500, for example a number-average molecular weight of about 550, about 800 or about 1000.
Suitable reactive polyisobutenes for preparing lubricant additives are in particular those which have a number-average molecular weight in the range from 1000 to 15 000, more preferably from 1300 to 12 500 and most preferably from 2000 to 10 000, for example a number-average molecular weight of about 1500, about 2000 or about 2300.
The reactive polyisobutenes preferably additionally have a polydispersity of less than 3.0, in particular less than 1.9 and more preferably of less than 1.7 or less than 1.5. Polydispersity refers to the quotient of weight-average molecular weight MW divided by the number-average molecular weight MN.
Particularly suitable reactive polyisobutenes are, for example, the Glissopal brands of BASF AG, in particular Glissopal 1000 (MN=1000) and Glissopal V 33 (MN=550) and Glissopal 2300 (MN=2300) and mixtures thereof, Other number-average molecular weights may be attained by a manner known in principle, by mixing polyisobutenes of different number-average molecular weights or by extractively enriching polyisobutenes of certain molecular weight ranges.
C2) Cold Flow Improvers
The additives improving cold properties (cold flow improvers) include middle distillate flow improvers (“MDFIs”), paraffin dispersants (“WASAs”) and the combination of the two additives (“WAFIs”).
The suitable cold flow improvers include in particular the following active substance groups, as described, for example, in WO 95/33805:
In the case of copolymers of ethylene with at least one further ethylenically unsaturated monomer (aa) the monomer is preferably selected from alkenylcarboxylic esters, (meth)acrylic esters and olefins.
Examples of suitable olefins are those having from 3 to 10 carbon atoms, and having from 1 to 3, preferably having 1 or 2, carbon-carbon double bonds, in particular having one carbon-carbon double bond. In the latter case, the carbon-carbon double bond may either be terminal (a-olefin) or internal. However, preference is given to α-olefins, more preferably α-olefins having from 3 to 6 carbon atoms, such as propene, 1-butene, 1-pentene and 1-hexene.
Examples of suitable (meth)acrylic esters are esters of (meth)acrylic acid with C1-C10-alkanols, in particular with methanol, ethanol, propanol, isopropanol, n-butanol, sec-butanol, isobutanol, tert-butanol, pentanol, hexanol, heptanol, octanol, 2-ethylhexanol, nonanol and decanol.
Examples of suitable alkenylcarboxylic esters are the vinyl and propenyl esters of carboxylic acids having from 2 to 20 carbon atoms whose hydrocarbon radical may be linear or branched. Among these, preference is given to the vinyl esters. Among the carboxylic acids having branched hydrocarbon radicals, preference is given to those whose branch is in the α-position to the carboxyl group and particular preference is given to the α-carbon atom being tertiary, i.e. to the carboxylic acid being a neocarboxylic acid. However, preference is given to the hydrocarbon radical of the carboxylic acid being linear.
Examples of suitable alkenylcarboxylic esters are vinyl acetate, vinyl propionate, vinyl butyrate, vinyl-2-ethylhexanoate, vinyl neopentanoate, vinyl hexanoate, vinyl neononanoate, vinyl neodecanoate and the corresponding propenyl esters, although preference is given to the vinyl esters. A particularly preferred alkenylcarboxylic ester is vinyl acetate.
Particular preference is given to selecting the ethylenically unsaturated monomer from alkenylcarboxylic esters.
Copolymers which contain two or more differing copolymerized alkenylcarboxylic esters are also suitable, and these differ in the alkenyl function and/or in the carboxylic group. Copolymers which, in addition to the alkenylcarboxylic ester(s), contain at least one copolymerized olefin and/or at least one copolymerized (meth acrylic ester are likewise suitable.
The ethylenically unsaturated monomer is copolymerized in the copolymer in an amount of preferably from 1 to 50 mol %, m re preferably from 10 to 50 mol % and in particular from 5 to 20 mol %, based on the entire copolymer.
The copolymer (aa) preferably has a number-average molecular weight Mn of from 1000 to 20 000, more preferably from 1000 to 10 000 and in particular from 1000 to 6000.
Examples of comb polymers (ab) are those described in “Comb-Like Polymers. Structure and Properties”, N. A. Platé and V. P. Shibaev, J. Poly. Sci. Macromolecular Revs. 8, pages 117 to 253 (1974). Among those described there, examples of suitable comb polymers are those of the formula II
where
Preferred comb polymers are obtainable, for example, by copolymerizing 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 then esterifying the anhydride or acid function with 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. Mixtures of comb polymers are also suitable. Comb polymers may also be polyfumarates or polymaleates, Homo- and copolymers of vinyl ethers are also suitable comb polymers.
Examples of suitable polyoxyalkylenes (ac) are polyoxyalkylene esters, ethers, ester/ethers and mixtures thereof. The polyoxyalkylene compounds preferably contain at least one linear alkyl group, more preferably at least two linear alkyl groups, having from 10 to 30 carbon atoms and a polyoxyalkylene group having a molecular weight of up to 5000. 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-0 061 895 and also in U.S. Pat. No. 4,491,455, which are fully incorporated herein by way of reference. Preferred polyoxyalkylene esters, ethers and ester/ethers have the general formula III
R19[—O—(CH2)y]xO—R20 (III)
where
Preferred polyoxyalkylene compounds of the formula III in which both R19 and R20 are R21 are polyethylene glycols and polypropylene glycols having a number-average molecular weight of from 100 to 5000. Preferred polyoxyalkylenes of the formula III in which one of the R19 radicals is R21 and the other is R21—CO— are polyoxyalkylene esters of fatty acids having from 10 to 30 carbon atoms, such as stearic acid or behenic acid. Preferred polyoxyalkylene compounds in which both R19 and R20 are an R21—CO— radical are diesters of fatty acids having from 10 to 30 carbon atoms, preferably of stearic or behenic acid.
The polar nitrogen compounds (ad) which are appropriately oil-soluble may be either ionic or nonionic and preferably have at least one, more preferably at least two, substituents of the formula >NR22 where R22 is a C8-C40-hydrocarbon radical. The nitrogen substituents may also be in quaternized form i.e. in cationic form. Examples of such nitrogen compounds include ammonium salts and/or amides which are obtainable by reacting at least one amine substituted by at least one hydrocarbon radical with a carboxylic acid having from 1 to 4 carboxyl groups or with a suitable derivative thereof. The amines preferably contain at least one linear C8-C40-alkyl radical. Examples of suitable primary amines include octylamine, nonylamine, decylamine, undecylamine, dodecylamine, tetradecylamine and the higher linear homologs. Examples of suitable secondary amines include dioctadecylamine and methylbehenylamine. Amine mixtures, in particular amine mixtures obtainable on the industrial scale, such as fatty amines or hydrogenated tallamines, are also suitable, as described, for example, in Ullmanns Encyclopedia of Industrial Chemistry, 6th edition, 2000 electronic release, Chapter “Amines, aliphatic”. Examples of acids suitable for the reaction include 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 polar nitrogen compounds are ring systems which bear at least two substituents of the formula -A-NR23R24 where A is a linear or branched aliphatic hydrocarbon group which is optionally interrupted by one or more groups selected from O, S, NR35 and CO, and R23 and R24 are each C9-C40-hydrocarbon radicals which are optionally interrupted by one or more groups selected from O, S, NR35 and CO, and/or substituted by one or more substituents selected from OH, SH and NR35R36 where R35 is C1-C40-alkyl which is optionally interrupted by one or more moieties which are selected from CO, NR35, O and S and/or substituted by one or more radicals selected from NR37R38, OR37, SR37, COR37, COOR37, CONR37R38, aryl or heterocyclyl, where R37 and R38 are each independently selected from H or C1-C4-alkyl; and R36 is H or R35.
A is preferably a methylene or polymethylene group having from 2 to 20 methylene units. Examples of suitable R23 and R24 radicals include 2-hydroxyethyl, 3-hydroxypropyl, 4-hydroxybutyl, 2-ketopropyl, ethoxyethyl and propoxypropyl. The cyclic system may be a homocyclic, heterocyclic, fused polycyclic or nonfused polycyclic system. The ring system is preferably carbo- or heteroaromatic, in particular carboaromatic. Examples of such polycyclic ring systems include fused benzoid structures such as naphthalene, anthracene, phenanthrene and pyrene, fused nonbenzoid structures such as azulene, indene, hydrindene and fluorene, nonfused polycycles such as diphenyl, heterocycles such as quinoline, indole, dihydroindole, benzofuran, coumarin, isocoumarin, benzthiophene, carbazole, diphenylene oxide and diphenylene sulfide, nonaromatic or partially saturated ring systems such as decalin, and three-dimensional structures such as α-pinene, camphene, bornylene, norbonane, norbonene, bicyclooctane and bicyclooctene.
Further examples of suitable polar nitrogen compounds are condensates of long-chain primary or secondary amines with carboxyl-containing polymers.
The polar nitrogen compounds specified hereinabove are described in WO 00/44857 and also in the references mentioned therein, which are fully incorporated herein by way of reference.
Suitable polar nitrogen compounds are also described in, for example, DE-A-198 48 621, DE-A-196 22 052 and EP-B-398 101, which are incorporated herein by way of reference.
Examples of suitable sulfo carboxylic acids/sulfonic acids and their derivatives (ae) are those of the general formula IV
where
Such sulfo carboxylic acids and sulfonic acids and their derivatives are described in EP-A-0 261 957, which is fully incorporated herein by way of reference.
Suitable poly(meth)acrylic esters (af) are both homo- and copolymers of acrylic and methacrylic esters. Preference is given to acrylic ester/homopolymers derived from C1-C40 alcohols. Preference is also given to copolymers of at least two differing (meth)acrylic esters which differ in respect of the esterified alcohol. The copolymer may also contain a further, different copolymerized olefinically unsaturated monomer. The weight-average molecular weight of the polymer is preferably from 50 000 to 500 000. A particularly preferred polymer is a copolymer of methacrylic acid and methacrylic esters of saturated C14- and C15-alcohols in which the acid groups are neutralized by hydrogenated tallamine. Suitable poly(meth)acrylic esters are described, for example, in WO 00/44857 which is fully incorporated herein by way of reference.
C2) Lubricity Improvers
The customary lubricity improvers include, for example, carboxylic acids, especially fatty acids, esters thereof, especially with polyols, mixtures of these acids and esters, ashlessly burning N-acyl compounds such as polyalkenylsuccinamides, mixtures of the acids and/or esters mentioned with these N-acyl compounds, as described, for example, in WO 96/23355, bis(hydroxyalkyl)fatty amines or hydroxyacetamides.
C3) Diluents
Inventive additives are frequently formulated together with solvents or diluents. Suitable diluents are, for example, the fractions obtained in crude oil processing, such as kerosene, naphtha or brightstock. Additionally suitable are aromatic and aliphatic hydrocarbons and alkoxyalkanols. Diluents used with preference for middle distillates, especially for diesel fuels, are naphtha, kerosene, diesel fuels, aromatic hydrocarbons such as Solvent Naphtha heavy, SolvessoR or ShellsolR and mixtures of these solvents and diluents.
D) Fuels and Lubricants
Fuels which are additized preferably in accordance with the invention are gasoline fuels and middle distillates such as diesel fuel, heating oil or kerosene, of which particular preference is given to diesel fuel.
The diesel fuels are, for example, mineral oil raffinates which typically have a boiling range of from 100 to 400° C. These are usually distillates having a 95% point up to 360° C. or even higher. These may also be “Ultra Low Sulphur Diesel” or “City Diesel” characterized by a maximum 95% point of, for example, 345° C. and a maximum sulfur content of 0.005% by weight, or by a 95% point of, for example, 285° C. and a maximum sulfur content of 0.001% by weight. Suitable in addition to the diesel fuels obtainable by refining are those which are obtainable by coal gasification or gas liquefaction (“gas-to-liquid” (GTL) fuels). Also suitable are mixtures of the aforementioned diesel fuels with renewable fuels such as biodiesel or bioethanol.
Particular preference is given to using the inventive additive for additizing diesel fuels having a low sulfur content, i.e. having a sulfur content of less than 0.05% by weight, preferably of less than 0.02% by weight, in particular of less than 0.005% by weight and especially of less than 0.001% by weight of sulfur.
The examples which follow illustrate the invention but without restricting it.
(R3,R4=methyl,x,z=3,y=1, R=polyisobutylene,Mn=550)
A four-neck flask equipped with nitrogen tap, internal contact thermosensor and distillation head with condenser is initially charged under nitrogen with a mixture of polyisobutenylsuccinic anhydride (PIBSA) (polyisobutenyl chain having Mn=550) in 2-ethylhexanol at 140° C. With vigorous stirring, N,N-dimethyldipropylenetriamine (DMAPAPA) is rapidly added dropwise. The molar ratio of PIBSA to amine used is 1:1.05 (succinic acid groups:amine). An exothermic reaction is observed with a temperature rise to 151° C., Subsequently, the reaction mixture is heated to 170° C. and stirred under nitrogen for 2.5 hours. Application of a vacuum of 500 mbar for 30 minutes then removes the alcohol present. Finally, the mixture is diluted to a 50% solution using Solvesso® 150.
(R3,R4=methyl,x,z=3, y=1,R=polyisobutenyl,Mn=1000)
The procedure of Example 1 is repeated, except that the corresponding molar amount of PIBSA 1000 (polyisobutenyl chain having Mn=1000) is used instead of PIBSA 550.
Determination of the Detergent Activity of Inventive Polyamines
The detergency of inventive polyamines in comparison to a commercial detergent additive was determined in a standardized test engine XUD9 (Peugeot engine) using the CEC F23 A 01 test method. In this test, the degree of carbonization of the nozzles was determined in the injection nozzle via the restriction of an air flow at needle stroke 0.1 mm. 100% flow restriction means full carbonization; 0% means no carbonization.
The following fuels were used:
The following additives having detergent action were used:
For all PIBSIs used, PIBSAs having a comparable degree of succinylation were used.
These additives were examined in the above-specified tests for their detergent action at different dosage in different diesel fuels. The percentage flow restriction values determined are compiled in the following Table 1:
Relative to the comparative substance used, the inventive additives exhibit distinctly better detergent activity at simultaneously lower dosage.
| Number | Date | Country | Kind |
|---|---|---|---|
| 04018696.7 | Aug 2004 | EP | regional |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP05/08533 | 8/5/2005 | WO | 3/9/2007 |
