Application of simultaneous rapeseed oil extraction and interesterification with methyl formate using enzymatic catalyst

Abstract

A novel method of interesterification of rapeseed oil utilising methyl fomate and an enzymatic catalyst to produce biodiesel without the need for glycerol separation was researched. Using the enzyme preparation Lipozyme TL IM as a catalyst, the simultaneous processes of oil extraction from rapeseed and interesterification in-situ were investigated. Three independent variables were assessed for their interaction and impact on the yield of rapeseed methyl esters: the mass ratio of methyl formate to rapeseed, the time, and the amount of catalyst. Utilising surface response methodology, process optimisation was performed, and a model explaining the impact of independent variables on the yield of rapeseed methyl esters was developed. Lab testing has verified that the optimal process parameters have been identified, resulting in a 94.24% rapeseed methyl ester yield. Using a 48:1 mass ratio of methyl formate to rapeseed and 23.33% of the enzymatic catalyst in 64.5 hours produced the highest yield. The reaction product contained conventional biodiesel (rapeseed methyl esters) along with mono-, di-, and triformyl glycerides. The interesterification product's physical and chemical characteristics were identified, and the resulting quality indicators were compared with the specifications of standards for biodiesel and mineral diesel fuel.