The high demand for fossil fuel has encouraged the search for substitutes of petroleum derivatives in order to reduce the
dependence of fossil fuel. A variety of fossil fuel programs and solutions have been suggested to help alleviate energy needs resulted in an alternative fuel called “biodiesel”. Biodiesel is an alkyl ester from reactions of fatty acids with short chain alcohols such as methanol or ethanol made by the
transesterification of oils or fats from either plants or animals sources in the presence of a
catalyst. In this study, we proposed a novel design of a heterogeneous catalyst; sulfonic acid-functionalized partially alkylsilylated NaY zeolite in catalyzing the transesterification reaction of palm oil. In this design, part of the external surface of the catalyst is covered by alkyl groups is hydrophobic in nature while the rest remain hydrophilic. It was prepared by the attachment of sulfonic acid as acid site and long chain alkyl groups from n-octadecyltrichlorosilane. Sulfonic acid groups were grafted onto the zeolite surface by oxidation of the –SH groups from 3-mercaptopropyltrimethoxysilane to the –SO3H form. We proposed that the acid sites could catalyze the transesterification of palm oil to produce fatty acid methyl esters and glycerol as the by-product, being adsorbed by the hydrophilic part of the catalyst. In this case, the yield of biodiesel could be increased. This catalyst was characterized by means of techniques such as XRD, NMR, TG/DTA, FTIR and acidic measurement by FTIR-pyridine adsorption. From the characterizations, the Brönsted acid sites and alkyl groups were proven to be attached onto the zeolite surface in order to catalyze the transesterification reaction.