Fuels compositions for direct injection gasoline engines

Abstract

Injector deposits in a direct injection gasoline engine are reduced by providing as fuel for the operation of said direct injection engine a fuel composition comprising a fuel-soluble compound having the formula (I): wherein R 1 and R 2 are independently C 1-4 alkyl, R 3 is a radical of the formula C m H 2m wherein m is an integer of 2 to 6, R 4 and R 5 are each independently (i) hydrogen (ii) C 1-4 alkyl, wherein R 6 is selected from the group consisting of hydrogen and C 1-4 alkyls and R 7 is selected from the group consisting of hydrogen and C 1-30 alkyl, (iv) wherein R 8 is a saturated or unsaturated, linear, branched or cyclic, C 7-23 hydrocarbyl group or (v) wherein R 4 and R 5 together with the nitrogen atom to which they are bonded, form a cyclic ring in which further hetero atoms.

1 . A method for controlling injector deposits in a direct injection gasoline engine which comprises introducing into a direct injection gasoline engine with the combustion intake charge a spark-ignition fuel composition comprising a) a spark-ignition fuel and b) a fuel-soluble compound having the formula (I):  
     
       
         
         
             
             
         
       
     
     wherein R 1  and R 2  are independently C 1-4  alkyl, R 3  is a radical of the formula C m H 2m  wherein m is an integer of 2 to 6, R 4  and R 5  are each independently (i)  
     
       
         
         
             
             
         
       
     
     wherein R 6  is selected from the group consisting of hydrogen and C 1-4  alkyls and R 7  is selected from the group consisting of hydrogen and C 1-30  alkyl, (ii)  
     
       
         
         
             
             
         
       
     
     wherein R 8  is a saturated or unsaturated, linear, branched or cyclic, C 7-23  hydrocarbyl group or (iii) wherein R 4  and R 5  together with the nitrogen atom to which they are bonded, form a cyclic ring in which further hetero atoms may be incorporated.  
   
   
       2 . The method of  claim 1  wherein the spark-ignition fuel composition comprises the fuel-soluble compound (b) in proportions effective to reduce the volume of injector deposits in a direct injection gasoline engine operated on a spark-ignition fuel containing an injector deposit-controlling amount of said fuel-soluble compound (b) to below the volume of injector deposits in said direct injection gasoline engine operated in the same manner on the same spark-ignition fuel except that it is devoid of a fuel-soluble compound (b).  
   
   
       3 . The method of  claim 1  wherein the spark-ignition fuel comprises gasoline.  
   
   
       4 . The method of  claim 1  wherein the spark-ignition fuel comprises a blend of hydrocarbons of the gasoline boiling range and a fuel-soluble oxygenated compound.  
   
   
       5 - 8 . (canceled)  
   
   
       9 . The method of  claim 1  wherein said fuel-soluble compound (b) comprises a compound of the formula:  
     
       
         
         
             
             
         
       
     
   
   
       10 . The method of  claim 1  wherein the fuel-soluble compound (b) is present in an amount sufficient to provide 0.1-15 pounds by weight of compound (b) per thousand barrels by volume of fuel.  
   
   
       11 . The method of  claim 10  wherein the fuel-soluble compound (b) is present in an amount sufficient to provide 0.3-10 pounds by weight of compound (b) per thousand barrels by volume of fuel.  
   
   
       12 . The method of  claim 1  wherein the fuel composition further comprises at least one amine detergent.  
   
   
       13 . The method of  claim 12  wherein said amine detergent comprises at least one member selected from the group consisting of nitrogen-containing derivatives of hydrocarbyl succinic acylating agents, high molecular weight Mannich condensation products, hydrocarbyl amines and polyetheramines.  
   
   
       14 . The method of  claim 1  wherein the fuel composition further comprises a carrier fluid selected from the group consisting of 1) a mineral oil or a blend of mineral oils that have a viscosity index of less than about 120, 2) one or more poly-α-olefin oligomers, 3) one or more poly (oxyalkylene) compounds having an average molecular weight in the range of about 500 to about 3000, 4) one or more polyalkenes, 5) one or more polyalkyl-substituted hydroxyaromatic compounds and 6) mixtures thereof.  
   
   
       15 . The method of  claim 14  wherein the carrier fluid comprises at least one poly (oxyalkylene) compound.  
   
   
       16 . The method of  claim 1  wherein the fuel composition further comprises at least one additive selected from the group consisting of antioxidants, carrier fluids, metal deactivators, dyes, markers, corrosion inhibitors, biocides, antistatic additives, drag reducing agents, demulsifiers, emulsifiers, dehazers, anti-icing additives, antiknock additives, anti-valve-seat recession additives, surfactants, lubricity additives and combustion improvers.  
   
   
       17 - 23 . (canceled)  
   
   
       24 . A method of controlling deposits in a direct injection gasoline engine comprising adding to a spark-ignition fuel a fuel-soluble compound comprising b) a fuel-soluble compound having the formula (I):  
     
       
         
         
             
             
         
       
     
     wherein R 1  and R 2  are independently C 1-4  alkyl, R 3  is a radical of the formula C m H 2m  wherein m is an integer of 2 to 6, R 4  and R 5  are each independently (i)  
     
       
         
         
             
             
         
       
     
     wherein R 6  is selected from the group consisting of hydrogen and C 1-4  alkyls and R 7  is selected from the group consisting of hydrogen and C 1-30  alkyl, (ii)  
     
       
         
         
             
             
         
       
     
     wherein R 8  is a saturated or unsaturated, linear, branched or cyclic, C 7-23  hydrocarbyl group or (iii) wherein R 4  and R 5  together with the nitrogen atom to which they are bonded, form a cyclic ring in which further hetero atoms may be incorporated and operating a direct injection gasoline engine using said fuel containing b).