Transesterification of coconut oil (Cocos nucifera L.) into biodiesel using zeolite-A catalyst based on rice husk silica and aluminum foil

In this research, zeolite-A was synthesized by hydrothermal method using silica of rice husk and aluminum foil as raw materials. For zeolite preparation, a particular amount of silica was dissolved in NaOH solution which is then aged with variation time of 24-96 hours, the mixed solution was then added with aluminum foil and again aged for 24 hours, the crystallization process was carried out in an oven of 100 °C 96 hours. The resulting zeolite was then calcined at 550 °C for 6 hours. The zeolite characterization by XRD showed that zeolite-A had been formed and had characteristics following the zeolite-A standard from IZA. The resulting zeolite-A has good crystallinity as indicated by the sharp peaks on the resulting diffractogram. The zeolite-A catalytic test on transesterification of coconut oil showed high catalyst performance, characterized by the conversion of fatty acids in coconut oil to methyl esters with 100% conversion percent. The formation of the methyl ester was proven based on the results of the analysis with FTIR and GCMS which showed the characteristics of methyl ester at wavenumbers 1744 cm⁻¹ (C═O), 2922 cm⁻¹ (C─H), 1170 cm⁻¹ (C─O), with the highest percentage in the form of methyl laurate at 31.80%. (paper)