Biodiesel production from Kesambi (Schleichera oleosa) oil using multi-walled carbon nanotubes supported zinc oxide as a solid acid catalyst

The development of heterogeneous catalysts for biodiesel production became a hot topic among scientists because of its many advantages including easy separation and catalyst reusability. In this study, multi-walled carbon nanotubes supported zinc oxide (MWCNTsZ) as a solid acid catalyst had been successfully prepared via the stober-like process. There are several % loading of ZnO variations ranging from 10 - 35 % of catalyst weight. These catalysts were characterized by x-ray diffraction (XRD), BET surface area analysis, and scanning electron microscope with energy-dispersive x-ray spectroscopy (SEM-EDX) analysis. Transesterification of kesambi (Schleichera oleosa) oil also had been done to test the activity of the solid catalyst. The potential of this catalyst is shown from its large surface area with the maximum surface area until 409 m²/gram. However, the quantity of dispersed zinc oxide (ZnO) on multi-walled carbon nanotubes (MWCNTs) via that modified Stober preparation is quite small lower than 5% weight. This phenomenon is resulting in a low yield of biodiesel after 3 h of transesterification reaction. The highest yield of biodiesel is obtained with 20% weight of loading ZnO variable producing 13.82% yield of methyl ester.