Fuel composition

Abstract

A fuel composition comprising: a diesel base fuel; from 1 to 10% v/v of a fatty acid alkyl ester; and more than 10% v/v of an ether component, the ether component comprising one or more ether compounds having in the range of from 8 to 12 carbon atoms and selected from compounds of formula I R 1 —O—R 2   (I) wherein R 1 and R 2 are independently primary or secondary alkyl.

We claim: 
     
         1 . A fuel composition comprising: a diesel base fuel; from 1 to 10% v/v of a fatty acid alkyl ester; and more than 10% v/v of an ether component, said ether component comprising one or more ether compounds having in the range of from 8 to 12 carbon atoms and selected from compounds of formula I
   R 1 —O—R 2   (I)
   
       wherein R 1  and R 2  are independently primary or secondary alkyl. 
     
     
         2 . The fuel composition of  claim 1  wherein the ether component comprises symmetrical ether compounds. 
     
     
         3 . The fuel composition of  claim 1  wherein the ether component comprises dipentyl ether. 
     
     
         4 . The fuel composition of  claim 1  wherein the ether component has a density of at least 0.770 g/cm 3 . 
     
     
         5 . The fuel composition of  claim 1  wherein the ether component has a flash point of at least 50° C. 
     
     
         6 . The fuel composition of  claim 1  wherein the ether component has a vapour pressure at 25° C. of at most 5 Torr. 
     
     
         7 . The fuel composition of  claim 1  wherein the ether component has a boiling point of at least 100° C. 
     
     
         8 . The fuel composition of  claim 1  wherein the ether component is a biofuel component. 
     
     
         9 . The fuel composition of  claim 1  wherein the ether component is present in an amount of from 15% to 90% v/v. 
     
     
         10 . The fuel composition of  claim 9  wherein the ether component is present in an amount of from 15% to 50% v/v. 
     
     
         11 . The fuel composition of  claim 1  wherein the ether component consists of one or more ether compounds having in the range of from 8 to 12 carbon atoms and selected from compounds of formula I
   R 1 —O—R 2   (I)
 
 
       wherein R 1  and R 2  are independently primary or secondary alkyl. 
     
     
         12 . The fuel composition of  claim 1  wherein the ether component has a density of at least 0.770 g/cm 3 , a flash point of at least 50° C., a vapour pressure at 25° C. of at most 5 Torr, and a boiling point of at least 100° C. 
     
     
         13 . The fuel composition of  claim 1  wherein the fuel composition has a measured cetane number of 40 or greater. 
     
     
         14 . A method of increasing the concentration of a biofuel component in a diesel fuel composition comprising blending more than 10% v/v of an ether compounds having in the range of from 8 to 12 carbon atoms and selected from compounds of formula I
   R 1 —O—R 2   (I)
   
       wherein R 1  and R 2  are independently primary or secondary alkyl. 
     
     
         15 . The method of  claim 14  wherein the diesel fuel composition contains a fatty acid ester or a fatty alcohol ester.