Croton megalocarpus oil: A feasible non-edible oil source for biodiesel production

This study presents the feasibility of converting a non-edible oil source native to the Africa region – croton megalocarpus oil to methyl esters (biodiesel) using sulfated tin oxide enhanced with SiO2 (SO42-/SnO2–SiO2) as super acid solid catalyst. This study was conducted using design of experiment (DoE), specifically, response surface methodology based on three-variable central composite design (CCD) with alpha (α) = 2. The reaction parameters studied are: reaction temperature (60–180 °C), reaction period (1–3 h) and methanol to oil ratio (1:6–1:24). Although the oil was found to contain high free fatty acid, however, yield up to 95% was obtained without any pre-treatment step with the following reaction conditions: 180 °C, 2 h and 15:1 methanol to oil molar ratio, while keeping constant catalyst concentration and stirring speed at 3 wt.% and 350–360 rpm, respectively.