Biodiesel production from refined sunflower vegetable oil over CaO/ZSM-5 catalysts

Abstract

Energy is a fundamental prerequisite for human existence. Due to continuous population growth, there is a need to find alternative energy sources. Biodiesel is a renewable source of energy which can be derived from plant oils or animal fats. This work focuses on the production of biodiesel from refined sunflower vegetable oil over the basic CaO/ ZSM-5 catalysts. Several loadings of CaO on ZSM-5 were prepared (5 wt. %, 15 wt. %, and 35 wt. %) and tested in the concerned reaction. The most active catalyst was found to be 35 wt. % CaO/ ZSM-5. The catalysts were all calcined at 800°C for 3 hours, characterized by N2 adsorption-desorption, XRD and FTIR techniques. The transesterification reaction was conducted in a batch reactor at a temperature of 60oC and atmospheric pressure. Reaction conditions were optimized by varying two factors: CTOR as well as the reaction time. The highest yield (89 %) was obtained after a reaction time of 2 hrs, a CTOR of 8 wt. %, and a MOMR of 12:1. The yield was calculated using gas chromatography (GC). The reusability of the 35 wt. % CaO/ ZSM-5 catalyst was also investigated and a significant drop in the yield (75 %) was observed. Properties of the produced biodiesel were measured and found to be in conformity with ASTM requirements.