Comparison of one step and two step process for biodiesel production fromwaste cooking oil using TGA analysis

Waste cooking oil(WCO)is one of theeconomical sources for biodiesel production.Transesterification of WCO with alkali catalyst islimited because the free fatty acidin it reacts withcatalyst and produces fine soap particles. The soapcausesan increase in viscosity, formation of gelswhichreduces catalyst efficiency andlowers theproduct yieldand makes the separation difficult. Inorder to avoid the problem of saponification, twostep acid-alkalicatalyzed process was selectedtoimprove the biodiesel yield from WCO.Themaximum yield of approximately 92.6evaluated forthe two step process for biodiesel production usingTGA analysis.