Activated carbon Alternative source Batch data processing Batch process Binary alloys Bio-diesel fuel Biodiesel Catalyst activity Catalyst synthesis Chromium alloys Chromium compounds Coconut shell Cooking palm oil Copper Electrosorption Fatty acid methyl ester Fatty acids Heterogeneous catalyst Metals Mixed oxides catalysts Palm oil Pore size Sol-gel process Sol-gels Thermodynamic stability Titanium alloys Titanium oxides Transesterification Wastewater