Use of quaternized alkyl amines as additive in fuels and lubricants

Abstract

The present invention relates to the use of quaternized alkylamine nitrogen compounds as a fuel additive and lubricant additive, such as, more particularly, as a detergent additive; for reduction or prevention of deposits in the injection systems of direct injection diesel engines, especially in common rail injection systems, for reduction of the fuel consumption of direct injection diesel engines, especially of diesel engines with common rail injection systems, and for minimization of power loss in direct injection diesel engines, especially in diesel engines with common rail injection systems; and as an additive for gasoline fuels, especially for operation of DISI engines.

1 . The use of a reaction product comprising a quaternized nitrogen compound, or of a fraction thereof which comprises a quaternized nitrogen compound and is obtained from the reaction product by purification, said reaction product being obtainable by
 reacting a quaternizable alkylamine comprising at least one quaternizable tertiary amino group with a quaternizing agent which converts the at least one tertiary amino group to a quaternary ammonium group,   the quaternizing agent being the alkyl ester of a cycloaromatic or cycloaliphatic mono- or polycarboxylic acid, especially of a mono- or dicarboxylic acid, or of an aliphatic polycarboxylic acid, especially dicarboxylic acid, a hydrocarbyl epoxide, optionally in combination with a free acid, or a dialkyl carbonate;   as a fuel additive or lubricant additive.   
     
     
         2 . The use according to  claim 1  as an additive for reducing the fuel consumption of direct injection diesel engines, especially of diesel engines with common rail injection systems, and/or for minimizing power loss in direct injection diesel engines, especially in diesel engines with common rail injection systems. 
     
     
         3 . The use according to  claim 1  as a gasoline fuel additive for reducing the level of deposits in the intake system of a gasoline engine, such as especially DISI and PFI (port fuel injector) engines. 
     
     
         4 . The use according to  claim 1  as a diesel fuel additive for reducing and/or preventing deposits in the injection systems, such as, more particularly, the internal diesel injector deposits (IDIDs), and/or valve sticking in direct injection diesel engines, especially in common rail injection systems. 
     
     
         5 . The use according to any of the preceding claims, wherein the alkylamine comprises at least one compound of the following general formula 3
   R a R b R c N  (3)
   in which   at least one of the R a , R b  and R c  radicals is a straight-chain or branched, saturated or unsaturated C 8 -C 40 -hydrocarbyl radical (especially straight-chain or branched C 8 -C 40 -alkyl) and the remaining radicals are identical or different, straight-chain or branched, saturated or unsaturated C 1 -C 6 -hydrocarbyl radicals (especially C 1 -C 6 -alkyl); or   in which all R a , R b  and R c  radicals are identical or different, straight-chain or branched, saturated or unsaturated C 8 -C 40 -hydrocarbyl radicals, especially straight-chain or branched C 8 -C 40 -alkyl radicals.   
     
     
         6 . The use according to any of the preceding claims, wherein the quaternizing agent is a compound of the general formula 1
   R 1 OC(O)R 2   (1)
   in which   R 1  is a lower alkyl radical and   R 2  is an optionally substituted monocyclic aryl or cycloalkyl radical, where the substituent is selected from OH, NH 2 , NO 2 , C(O)OR 3 , and R 1 OC(O)—, in which R 1  is as defined above and R 3  is H or R 1 .   
     
     
         7 . The use according to any of  claims 1  to  5 , wherein the quaternizing agent is a compound of the general formula 2
   R 1 OC(O)-A-C(O)OR 1a   (2)
 
 in which 
 R 1  and R 1a  are each independently a lower alkyl radical and 
 A is an optionally mono- or polysubstituted hydrocarbylene such as, more particularly, an optionally mono- or polysubstituted alkylene or alkenylene. 
 
     
     
         8 . The use according to any of  claims 1  to  5 , wherein the quaternizing agent comprises an epoxide of the general formula 4 
       
         
           
           
               
               
           
         
         where 
         the R d  radicals present therein are the same or different and are each H or a hydrocarbyl radical, where the hydrocarbyl radical is an aliphatic or aromatic radical having at least 1 to 10 carbon atoms and the free acid of the quaternizing agent is a free protic acid, especially a C 1-12 -monocarboxylic acid or -dicarboxylic acid. 
       
     
     
         9 . The use according to any of the preceding claims, wherein the quaternizable tertiary amine is a compound of the formula 3 in which at least two of the R a , R b  and R c  radicals are the same or different and are each a straight-chain or branched C 10 -C 20 -alkyl radical and the other radical is C 1 -C 4 -alkyl. 
     
     
         10 . The use according to any of the preceding claims, wherein the quaternizing agent is selected from lower alkylene oxides in combination with a monocarboxylic acid, alkyl salicylates, dialkyl phthalates and dialkyl oxalates. 
     
     
         11 . The use according to any of the preceding claims, wherein the fuel is selected from diesel fuels, biodiesel fuels, gasoline fuels, and alkanol-containing gasoline fuels. 
     
     
         12 . A quaternized nitrogen compound as defined in any of  claims 1  to  10 . 
     
     
         13 . A process for preparing a quaternized nitrogen compound according to  claim 12 , comprising the reaction of a quaternizable alkylamine comprising at least one quaternizable tertiary amino group with a quaternizing agent which converts the at least one tertiary amino group to a quaternary ammonium group,
 the quaternizing agent being the alkyl ester of a cycloaromatic or cycloaliphatic mono- or polycarboxylic acid, especially of a mono- or dicarboxylic acid, or of an aliphatic polycarboxylic acid, especially dicarboxylic acid, or a hydrocarbyl epoxide in combination with an acid.   
     
     
         14 . An additive concentrate comprising, in combination with further diesel fuel additives or gasoline fuel additives or lubricant additives, at least one quaternized nitrogen compound as defined in  claim 12  or prepared according to  claim 13 . 
     
     
         15 . A fuel composition or lubricant composition comprising, in a majority of a customary fuel or lubricant, a proportion of at least one reaction product comprising a quaternized nitrogen compound, or of a fraction thereof which comprises a quaternized nitrogen compound and is obtained from the reaction product by purification, said reaction product being obtainable by
 reacting a quaternizable alkylamine comprising at least one quaternizable tertiary amino group with a quaternizing agent which converts the at least one tertiary amino group to a quaternary ammonium group,   the quaternizing agent being the alkyl ester of a cycloaromatic or cycloaliphatic mono- or polycarboxylic acid, especially of a mono- or dicarboxylic acid, or of an aliphatic polycarboxylic acid, especially dicarboxylic acid, an alkyl epoxide, optionally in combination with a free acid, or a dialkyl carbonate.   
     
     
         16 . The fuel composition or lubricant composition according to  claim 15 , wherein the alkylamine comprises at least one compound of the following general formula 3
   R a R b R c N  (3)
   in which   at least one of the R a , R b  and R c  radicals is a straight-chain or branched, saturated or unsaturated C 8 -C 40 -hydrocarbyl radical (especially straight-chain or branched C 8 -C 40 -alkyl) and the remaining radicals are identical or different, straight-chain or branched, saturated or unsaturated C 1 -C 6 -hydrocarbyl radicals (especially C 1 -C 6 -alkyl); or   in which all R a , R b  and R c  radicals are identical or different, straight-chain or branched, saturated or unsaturated C 8 -C 40 -hydrocarbyl radicals, especially straight-chain or branched C 8 -C 40 -alkyl radicals.   
     
     
         17 . The fuel composition or lubricant composition according to either of  claims 15  and  16 , wherein the quaternizing agent is a compound of the general formula 1
   R 1 OC(O)R 2   (1)
 
 in which 
 R 1  is a lower alkyl radical and 
 R 2  is an optionally substituted monocyclic aryl or cycloalkyl radical, where the substituent is selected from OH, NH 2 , NO 2 , C(O)OR 3 , and R 1 OC(O)—, in which R 1  is as defined above and R 3  is H or R 1 . 
 
     
     
         18 . The fuel composition or lubricant composition according to either of  claims 15  and  16 , wherein the quaternizing agent is a compound of the general formula 2
   R 1 OC(O)-A-C(O)OR 1a   (2)
 
 in which 
 R 1  and R 1a  are each independently a lower alkyl radical and 
 A is an optionally mono- or polysubstituted hydrocarbylene such as, more particularly, an optionally mono- or polysubstituted alkylene or alkenylene. 
 
     
     
         19 . The fuel composition or lubricant composition according to either of  claims 15  to  16 , wherein the quaternizing agent comprises an epoxide of the general formula 4 
       
         
           
           
               
               
           
         
         where 
         the R d  radicals present therein are the same or different and are each H or a hydrocarbyl radical, where the hydrocarbyl radical is an aliphatic or aromatic radical having at least 1 to 10 carbon atoms and the free acid of the quaternizing agent is a free protic acid, especially a C 1-12 -monocarboxylic acid or -dicarboxylic acid. 
       
     
     
         20 . The fuel composition or lubricant composition according to any of  claims 15  to  19 , wherein the quaternizable tertiary amine is a compound of the formula 3 in which at least two of the R a , R b  and R c  radicals are the same or different and are each a straight-chain or branched C 10 -C 20 -alkyl radical and the other radical is C 1 -C 4 -alkyl. 
     
     
         21 . The fuel composition or lubricant composition according to any of  claims 15  to  20 , wherein the quaternizing agent is selected from lower alkylene oxides in combination with a monocarboxylic acid, alkyl salicylates, dialkyl phthalates and dialkyl oxalates. 
     
     
         22 . The fuel composition or lubricant composition according to any of the preceding  claims 15  to  21 , selected from diesel fuels, biodiesel fuels, gasoline fuels, and alkanol-containing gasoline fuels.