Characterization of microwave-assisted sulfonated glucose catalyst for esterification of palm fatty acid distillate to biodiesel

Abstract

This study was carried out to solve the problem involving catalyst usage by practicing a heterogeneous solid acid catalyst, which require a low-cost production, easy preparation process, high effectiveness, environmental friendly and suitable to be used in the esterification process involving waste oil containing high level of free fatty acids. This paper investigated the sulfonated incomplete carbonised glucose (SO 3 H/ICG) catalysts prepared via microwave-assisted which involve carbonisation and sulfonation processes. Thorough screening covering the power level of microwave (W), heating time (min) as well as weight of D(+)-glucose (g) were studied to generate the optimum condition for carbonisation process. Sulfonation of the catalyst were prepared at 7 min using 4 g of ICG; 100 ml H2SO4 and medium high power level (560 W).The physical and chemical properties of the sulfonated catalyst were analyzed by X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Brunauer-Emmett-Teller (BET) and Ammonia Temperature Programmed Desorption (TPD-NH3). For the esterification of palm fatty acid distillate (PFAD), a classic conventional reflux system was used. It is found that 20 g of D(+)-glucose heated at 20 min in medium power level (400 W) provides the optimum carbonisation parameters due to its highest yield of fatty acid methyl ester (FAME) produced, 91.41 %.