Synthesis of biodiesel using new basic ionic liquid as catalyst

Basic ionic liquids were synthesized and used as green catalyst in the synthesis of biodiesel by castor oil,which a reusable ionic liquid 1-butyl-3-methylimidazolium hydroxide(OH) was selected and characterized.The optimum process conditions were as follows:the catalyst amounts was 1%,molar ratio of methanol to castor oils 6 ∶1,the reaction temperature 40 ℃,the reaction time was 60 min.In these conditions,the conversion of castor oil to methyl ester was above 95%,the yield of mixed methyl ester was up to 97%.The ionic liquid OH was stable and could be repeatedly used six times.