CaO from local limestone : a novel catalyst for green diesel production

Abstract

Energy is a key essential for human presence. Due to persistent population development, there is a necessity to find alternate energy sources. The aim of this work is the production of biodiesel, a renewable energy source, through the transesterification of refined sunflower oil using calcium oxide (CaO) as basic solid catalyst. CaO catalyst was obtained through the calcination of limestone rocks (powder form) rich in CaCO3 at 800 °C for 2 hours before any transesterification reaction. CaO fresh catalyst was characterized using Fourier Transform Infrared Spectroscopy (FTIR). All the transesterification reactions were performed in a round bottom flask batch reactor at atmospheric pressure, a temperature of 60 °C, a methanol to oil ratio (MOMR) of 12:1, a catalyst to oil ratio (CTOR) of 10 wt%, and a stirring speed of 400 rpm. In order to optimize the reaction conditions, reaction time was varied in order to record the highest biodiesel (Fatty acid methyl ester) yield. The highest yield (98%) was obtained using a methanol to oil ratio (MOMR) of 12:1, a catalyst to oil ratio (CTOR) of 10 wt%, a stirring speed of 400 rpm and after a reaction time of 4 hours.