Fuel compositions

Abstract

Disclosed is a diesel fuel composition containing 2-ethylhexyl nitrate (2-EHN) and one or more organic peroxides for providing improved fuel economy. The organic peroxides may have a cyclic peroxide of the general formula (I).

We claim: 
     
         1 . A diesel fuel composition comprising a diesel base fuel, 2-ethylhexylnitrate and one or more peroxides selected from the group of peroxides represented by the general formula (I) below: 
       
         
           
           
               
               
           
         
         wherein R 1 , R 3 , and R 5  are independently selected from the group consisting of hydrogen, C 1 -C 20  alkyl, C 3 -C 20  cycloalkyl, C 6 -C 20  aryl, C 7 -C 20  aralkyl and C 7 -C 20  alkaryl, which groups may include linear or branched alkyl moieties; R 2 , R 4  and R 6  are independently selected from the group consisting of hydrogen, C 2 -C 20  alkyl, C 3 -C 20  aryl, C 7 -C 20  aralkyl, and C 7 -C 20  alkaryl, which groups may include linear or branched alkyl moieties; and each of R 1  to R 6  may optionally be substituted with one or more groups selected from hydroxyl, alkoxy, linear or branched alkyl, aryloxy, ester, carboxy, nitrile, and amido. 
       
     
     
         2 . The diesel fuel composition of  claim 1  wherein the amount of the one or more peroxides is in the range of from 0.001% w/w to 1% w/w, based on the weight of the total diesel fuel composition. 
     
     
         3 . The diesel fuel composition of  claim 1  wherein the amount of 2-ethylhexyl nitrate is in the range of from 0.001% w/w to 1% w/w, based on the weight of the total diesel fuel composition. 
     
     
         4 . The diesel fuel composition of  claim 1  wherein at least one of the peroxides in the fuel composition is derived from one or more ketones selected from the group consisting of acetone, methyl-n-amyl ketone, ethyl butyl ketone, ethylpropyl ketone, methylheptyl ketone, methylhexyl ketone, ethylamyl ketone, methylpropyl ketone, diethyl ketone, methylethyl ketone, isomers of these ketones, and mixtures thereof. 
     
     
         5 . The diesel fuel composition of  claim 1  wherein the cyclic ketone peroxide of general formula (I) is selected from the group consisting of cyclic methylethyl ketone peroxide, cyclic methylisobutyl ketone peroxide, and cyclic methylisopropyl ketone peroxide. 
     
     
         6 . The diesel fuel composition of  claim 1  comprising 2-ethylhexylnitrate and cyclic methylethyl ketone peroxide. 
     
     
         7 . The diesel fuel composition of  claim 6  wherein the cyclic methylethyl ketone peroxide is 3,6,9-triethyl-3,6,9-trimethyl-1,4,7-triperoxonane. 
     
     
         8 . The diesel fuel composition of  claim 1  further comprising one or more fuel additives. 
     
     
         9 . A method of operating an internal combustion engine and/or a vehicle powered by such an engine comprising introducing into a combustion chamber of the engine the diesel fuel composition of  claim 1  and operating the internal combustion engine and/or the vehicle powered by such an engine. 
     
     
         10 . A method of improving the fuel economy performance of an internal combustion engine comprising introducing into a combustion chamber of the internal combustion engine a diesel fuel composition of  claim 1 .