Efficient biodiesel production from waste cooking oil using p-toluenesulfonic acid doped polyaniline as a catalyst

p-Toluenesulfonic acid doped polyaniline was developed as a catalyst for the production of biodiesel from waste cooking oil. The physical and chemical properties of the obtained catalyst were characterized in detail. It was found that the yield of fatty acid methylesters reached 97.1%, and the physical properties of the obtained biodiesel sample satisfied the requirement of ASTM D6751 standards. In addition, the catalyst exhibited excellent stability for 10 runs. Therefore, this heterogeneous catalyst has potential for biodiesel production from waste cooking oil, so further pilot tests deserve to be carried out and may be used in large-scale industries.