POROUS CALCIUM OXIDE CATALYSTS FROM GREEN-MUSSEL SHELLS FOR BIODIESEL PRODUCTION

Abstract

In this research, the transesterification of refined palm oil with methanol was studied using catalysts derived from waste green-mussel shells as a raw material. The catalysts were synthesized by direct calcination of pure CaCO3, a major component of green-mussel shells, at 900 oC for 5 h. The properties of the synthesized catalyst such as morphology, specific surface area and the structure of crystalline phase were characterized using X-ray powder diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FSEM), Brunauer-Emmett-Teller (BET) surface area analysis and N2 adsorption-desorption measurement. Moreover, the CaO were converted to Ca(OH)2 phase as indicated from the XRD results after the modification of CaO using hydration method in a little amount of deionized water. The 4 wt. % of CaO-EGMShell and 3 wt. % of Ca(OH)2-EGMShell amounts of catalyst showed good catalytic activities under the optimum condition of methanol to oil molar ratio of 1:6, reaction temperature of 64 ± 1 oC at constant speed agitation of 700 rpm for the synthesis of biodiesel. The conversion exceeding 98 % and 97 % yield of biodiesel were obtained when the reaction was carried out for 2.5 h. Furthermore, the CaO-EGMShell and Ca(OH)2-EGMShell catalysts were able to be reused up to 5 and 3 cycles, respectively without deterioration in its activity with the biodiesel conversion above 90 %. Besides, the biodiesels with the ester content of over 97 % in this work are in accordance with the European standard, EN 14103.