Enhanced biodiesel production from waste cooking oils catalyzed by sodium hydroxide supported on heterogeneous co-catalyst of bentonite clay

Abstract

Various proportions of bentonite clay performing as co-catalysts were evaluated for the production of biodiesel from waste cooking oil (WCO). The results showed that the use of bentonite as a heterogeneous co-catalyst could significantly increase the biodiesel yield by approximately 50% of the control. The heterogeneous co-catalyst of bentonite clay improved the properties of the produced biodiesel including acid number, free fatty acids (FFA), relative density, kinematic viscosity and flash point fulfilling with the standard ASTM limits and the European Biodiesel Standard (EN 14214). The use of bentonite clay in the transesterification of WCO could also enhance the conductivity of the produced biodiesel from 11 to 100 µS•m -1 .