This work focuses on the development of heterogeneous catalysts for biodiesel production from high free fatty acid (FFA) containing
Jatropha curcas oil (JCO). Solid base and acid catalysts were prepared and tested for transesterification in a batch reactor under mild reaction conditions. Mixtures of solid base and acid catalysts were also tested for single-step simultaneous esterification and transesterification. More soap formation was found to be the main problem for calcium oxide (CaO) and lithium doped calcium oxide (Li–CaO) catalysts during the reaction of jatropha oil and methanol than for the rapeseed oil (RSO). CaO with Li doping showed increased conversion to biodiesel than bare CaO as a catalyst. La
3 and La
3 catalysts were also tested and among them La
3–ZnO showed higher activity. Mixture of solid base catalysts (CaO and Li–CaO) and solid acid catalyst (Fe
3) were found to give complete conversion to biodiesel in a single-step simultaneous esterification and transesterification process.
►Various heterogeneous catalysts for conversion of high free fatty acid (FFA) containing jatropha oil to biodiesel.►First ever approach with simultaneous esterification and transesterification using solid base and solid acid catalysts.►Characterization of surface properties of catalysts and the properties of the oil and biodiesel.►Experimental validation and biodiesel production under mild reaction conditions.