Lubricating composition for use in diesel engines compatible with biofuel

Abstract

The present invention provides a lubricating composition for use in diesel engines compatible with biofuel, the lubricating composition comprising a base oil belonging to Group III and/or Group II of the API base oil categories, from 0.5 to 5% by mass of a phenolic anti-oxidant and from 0.5 to 5% by mass of an amine-based anti-oxidant, the total content of the anti-oxidants being at least 2% by mass.

1 . A lubricating composition for use in diesel engines compatible with biofuel, the lubricating composition comprising a base oil belonging to Group III or Group II of the API base oil categories, from 0.5 to 5% by mass of a phenolic anti-oxidant and from 0.5 to 5% by mass of an amine-based anti-oxidant, the total content of the anti-oxidants being at least 2% by mass. 
     
     
         2 . A lubricating composition according to  claim 1  wherein the phenolic anti-oxidant is a 6-methylheptyl alcohol ester of 3-(4-hydroxy-3,5-di-t-butyl-phenyl)propionic acid. 
     
     
         3 . A lubricating composition according to  claim 1  wherein the amine-based anti-oxidant is a diphenylamine which is a reaction product of N-phenylbenzeneamine and 2,4,4-trimethylpentene. 
     
     
         4 . A lubricating composition according to  claim 1  wherein the biofuel used in the diesel engine is derived from rapeseed oil. 
     
     
         5 . The use of the lubricating composition according to  claim 1  in a diesel engine. 
     
     
         6 . The use according to  claim 5 , wherein a biofuel is used in the diesel engine. 
     
     
         7 . A method of operating a diesel engine comprising lubricating the diesel engine with a lubricating composition according  claim 1  and using a biofuel derived from rapeseed oil as fuel.