CHARACTERIZATION AND CATALYTIC PERFORMANCE ON TRANSESTERIFICATION OF PALM OLEIN OF POTAS- SIUM OXIDE SUPPORTED ON RH-MCM-41 FROM RICE HUSK SILICA
Keywords:
RH-MCM-41, MCM-41, K2O, Transesterification, Biodiesel, Heterogeneous catalysisAbstract
A mesoporous material, RH-MCM-41, was synthesized with a rice husk silica source by hydrothermalmethod. The obtained material showed characteristic X-ray diffraction peaks of the (100), (110), and(200) planes at 2.3, 4.0 and 4.7 degrees, respectively, and possessed a high specific surface area of 1,231m2/g and narrow pore size distribution in the range of 1.8 - 4.2 nm. It was used as a catalytic support forpotassium oxide (K2O) from a CH3COOK precursor to produce K2O/RH-MCM-41 with K2O loadingof 4, 8, and 12%wt. Upon loading with K2O, the RH-MCM-41 surface area decreased significantlyindicating the collapse of the mesoporeous structure, and the tendency to collapse increased with theK2O loading. The K2O/RH-MCM-41 catalysts were tested for biodiesel production from palm oleinoil and methanol via transesterification at 50, 75, and 100°C. The catalyst with 8%K2O loading gavethe highest conversion at all tested temperatures. At this loading, the activity increased with thetemperature and the highest conversion was 84% at 100°C. Products from transesterification weremainly methyl palmitate (C16) and unsaturated methyl ester (oleate, linoleate and linolenate, C18).
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