Sustainable approach to biodiesel synthesis via thermally induced transesterification using biochar as surrogate porous media

This study validates whether maize residue biochar could be used as surrogate porous media for thermally induced transesterification of waste cooking oil. The highest yield of fatty acid methyl esters (FAMEs) reached up to 91% at 300 degrees C with the biochar while it reached at 380 degrees C with silica. This suggests that energy saving can be expected using biochar in the biodiesel production process. Larger pore size and wider pore distribution of the biochar likely provides favorable conditions for the high biodiesel yield at lower temperature than silica. Based on similar FAME yields between refined soybean oil and waste cooking oil, the thermally induced transesterification with the biochar exhibited an extraordinary tolerance against impurities in waste cooking oil.