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 : A method for reducing and/or preventing internal diesel injector deposits in a direct injection diesel engine, the method comprising
 adding to a diesel or biodiesel fuel a reaction product comprising a quaternized nitrogen compound, or a fraction of said reaction product which comprises the quaternized nitrogen compound and which is obtained from the reaction product by purification,   wherein said reaction product is obtained by   reacting a quaternizable alkylamine comprising at least one quaternizable tertiary amino group with a quaternizing agent which converts the at least one quaternizable tertiary amino group to a quaternary ammonium group,   wherein the quaternizable alkylamine comprises at least one compound of the following formula 3
   R a R b R c N  (3)
 
   in which   at least one of the R a , Rb and R c  radicals is a straight-chain or branched, saturated or unsaturated C 8 -C 40 -hydrocarbyl radical and the remaining radicals are identical or different, straight-chain or branched, saturated or unsaturated C 1 -C 6 -hydrocarbyl radicals; or   in which all R a , Rb and R c  radicals are identical or different, straight-chain or branched, saturated or unsaturated C 8 -C 40 -hydrocarbyl radicals, and   the quaternizing agent is the alkyl ester of a cycloaromatic or cycloaliphatic mono- or polycarboxylic acid, or of an aliphatic polycarboxylic acid, a hydrocarbyl epoxide, optionally in combination with a free acid, or a dialkyl carbonate.   
     
     
         2 : The method according to  claim 1 , wherein the adding further reduces and/or prevents valve sticking in the direct injection diesel engine. 
     
     
         3 : The method according to  claim 1 ,
 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 the group consisting of OH, NH 2 , NO 2 , C(O)OR 3 , and R 1 OC(O)—, and R 3  is H or R 1 .   
     
     
         4 : The method according to  claim 1 ,
 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.   
     
     
         5 : The method according to  claim 1 ,
 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. 
       
     
     
         6 : The method according to  claim 1 ,
 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.   
     
     
         7 : The method according to  claim 1 ,
 wherein the quaternizing agent is selected from the group consisting of lower alkylene oxides in combination with a monocarboxylic acid, alkyl salicylates, dialkyl phthalates and dialkyl oxalates.   
     
     
         8 : The method according to  claim 1 , wherein the reaction product or fraction thereof is added to diesel fuel. 
     
     
         9 . The method according to  claim 5 , wherein R 2  is a C 1  alkyl radical, a C 2  alkyl radical or a C 3  alkyl radical and R2 is a phenyl substituted with HO— or an ester of formula R 1a OC(O)—, which is in an ortho position relative to the R 1 OC(O) radical. 
     
     
         10 . The method according to  claim 1 , wherein at least one of the R a , Rb and R c  radicals is a straight-chain or branched C 8 -C 40 -alkyl.