Potential Heterogeneous Catalysts from Three Biogenic Residues toward Sustainable Biodiesel Production: Synthesis and Characterization

The cost and difficulty in the preparation of synthetic heterogeneous base catalysts is the main barrier to their use. Today, the majority of these catalysts are derived from biomass resources. This study aimed at developing and characterizing these catalysts from three biogenic residues for biodiesel production without catalyst support. The EDS indicated the variation of Na, K, Mg, and Ca, having aggregates of 67.45, 83.15, and 76.85 % in calcined- periwinkle shell-ash (CPWSA), -melon seed-husk ash (CMSHA) and -locust bean pod ash (CLBPA), respectively. XRD revealed the presence of sodium oxide (Na₂O), calcium oxide (CaO), potassium oxide (K₂O), and magnesium oxide (MgO) in the catalysts at 800 °C. The FTIR showed the presence of C=O, C−H, and O−H bonds in the catalyst samples. The basicity values of CPWSA, CMSHA, and CLBPA are 11.65, 10.41, and 11.62, respectively. The developed catalysts were used to synthesize biodiesel from palm kernel oil.