Tertiary amines for reducing injector nozzle fouling in direct injection spark ignition engines

Abstract

Use of a tertiary hydrocarbyl amine with C 1 - to C 20 -hydrocarbyl residues, the overall number of carbon atoms not exceeding 30, as an additive in gasoline for reducing injector nozzle fouling in direct injection spark ignition engines. A fuel additive composition essentially comprising nitrogen-containing dispersants, carrier oils, the above tertiary hydrocarbyl amines and optionally friction modifiers. A fuel composition comprising a major amount of gasoline and a minor amount of the above fuel additive composition.

1 . A composition, comprising:
 unleaded gasoline, and   a tertiary hydrocarbyl amine of formula (I)   
       
         
           
           
               
               
           
         
         wherein 
         R 1 , R 2  and R 3  are each independently a C 1 - to C 20 -hydrocarbyl residue with the proviso that an overall number of carbon atoms in formula (I) does not exceed 30. 
       
     
     
         2 . The composition according to  claim 1 , wherein
 at least two of R 1 , R 2  and R 3  are different, and   among R 1 , R 2 , and R 3 , a hydrocarbyl residue with most carbon atoms differs in carbon atom number from a hydrocarbyl residue with second most carbon atoms by at least 3.   
     
     
         3 . The composition according to  claim 1 , wherein
 one or two of R 1 , R 2 , and R 3  are C 7 - to C 20 -hydrocarbyl residues, and   the remaining two or one of R 1 , R 2 , and R 3  are C 1 - to C 4 -hydrocarbyl residues.   
     
     
         4 . The composition according to  claim 1 , wherein
 R 1  is a C 8 - to C 18 -hydrocarbyl residue, and   R 2  and R 3  are each independently a C 1 - to C 4 -alkyl radical.   
     
     
         5 . The composition according to  claim 1 , wherein
 R 1  is a C 9 - to C 16 -hydrocarbyl residue, and   R 2  and R 3  are each a methyl radical.   
     
     
         6 . A fuel additive composition, comprising:
 (A) at least one nitrogen-comprising dispersant selected from the group consisting of
 (A1) a polyisobutenyl monoamine, 
 (A2) a polyisobutenyl polyamine, 
 (A3) a Mannich reaction product of a substituted phenol with an aldehyde and a mono- or polyamine, and 
 (A4) a polyoxyalkylene terminated by a mono- or polyamino group; 
   (B) a carrier oil in the presence of (A1), (A2), or (A3), wherein the carrier oil is substantially free of nitrogen and is selected from the group consisting of a synthetic carrier oil and a mineral carrier oil;   (C) a tertiary hydrocarbyl amine of formula (I),   
       
         
           
           
               
               
           
         
          wherein R 1 , R 2  and R 3  are each independently a C 1 - to C 20 -hydrocarbyl residue with the proviso that an overall number of carbon atoms in formula (I) does not exceed 30; and 
         (D) optionally, a friction modifier. 
       
     
     
         7 . The fuel additive composition according to  claim 6 , wherein the at least one nitrogen-comprising dispersant (A) is a polyisobutenyl monoamine with a number average molecular weight of from 550 to 1000. 
     
     
         8 . The fuel additive composition according to  claim 6 , wherein a weight ratio of the at least one nitrogen-comprising dispersant (A) to the tertiary hydrocarbyl amine of formula (I) (C) is of from 0.3:1 to 25:1. 
     
     
         9 . A fuel composition comprising
 a major amount of a liquid fuel in gasoline boiling range, and   a minor amount of the fuel additive composition according to  claim 6 .   
     
     
         10 . The fuel composition according to  claim 9 , wherein
 the at least one nitrogen-comprising dispersant (A) is present at a level of from more than 50 to 3000 ppm,   the carrier oil (B), if present, is at a level of from 50 to 2000 ppm,   the tertiary hydrocarbyl amine of formula (I) (C) is at a level of from 10 to 3000 ppm, and   the friction modifier (D), if present, is at a level of from 5 to 2000 ppm.   
     
     
         11 . A method of reducing injector nozzle fouling in an unleaded gasoline composition, the method comprising:
 adding an additive comprising an effective concentration of a tertiary hydrocarbyl amine of formula (I)   
       
         
           
           
               
               
           
         
          into an unleaded gasoline composition in need thereof, 
         wherein 
         R 1 , R 2  and R 3  are each independently a C 1 - to C 20 -hydrocarbyl residue with the proviso that an overall number of carbon atoms in formula (I) does not exceed 30.