Biodiesel production by transesterification reaction of sunflower vegetable oil over CaO/ZSM5 catalysts

Abstract

Biodiesel obtained by transesterification reaction of sunflower oil (Plein Soleil) using CaO supported on ZSM5 catalysts was carried on. To determine the catalytic performance of CaO/ZSM5 catalysts in the transesterification of sunflower oil, a series of experiments were conducted using CaO/ZSM5 catalysts in the presence of methanol. Numerous CaO loadings (5, 15 and 35wt.%) were impregnated on zeolite. These catalysts were prepared by calcination at 800°C for 3 hours and then characterized by Fourier Transform Infrared Spectroscopy (FTIR) and X-ray diffraction (XRD) techniques. The catalytic reactions were done using a round bottom flask of 500 ml at 600C and atmospheric pressure. 35 wt.% CaO/ZSM5 displayed the highest catalytic performance. The optimum conditions in the presence of 35 wt.% CaO/ZSM5 catalysts were obtained through modification of the catalyst to oil molar ratio, methanol to oil ratio and the reaction time. The highest fatty acids methyl ester conversion (90.3%) was obtained after 2 hours with a catalyst to oil ratio of 10 wt. % and a methanol to oil molar ratio of 4:1. The catalyst reusability was also studied and showed that the 35 wt.% CaO/ZSM5 catalysts is stable for three consecutive runs. The kinematic viscosity, the density and the flash point of the obtained biodiesel are in accordance with ASTM requirements.