Biodiesel Production from Waste Coconut Oil in Coconut Milk Manufacturing

Abstract

The purpose of this research was to develop a 3 step biodiesel production from waste coconut oil taken from a wastewater pond in a coconut milk manufacturing plant. Special attention was paid to optimizing the first step, acid catalyzed hydrolysis, to convert the waste coconut oil into high free fatty acid oil, 83.32 wt%. The first step was the acid hydrolysis, in order to produce high free fatty acid oil. The optimum condition in acid hydrolysis was 5 % by mass of hydrochloric acid, in order to produce high free fatty acid oil that could be used as raw material for biodiesel production. The second step was the acid esterification, in order to reduce the FFA and convert FFA to methyl ester. The reduction of the FFA from 83.32 % in high free fatty acid oil to less than 2 % required 3 % by mass of hydrochloric acid, a molar ratio of methanol to oil of 10: 1, and a reaction time of 60 min. The alkaline transesterification in the third step was used triglyceride at 1.0wt% of KOH for catalysis, a molar ratio of methanol to oil of 6:1, and a reaction time of 60 min. The waste coconut oil biodiesel was further evaluated by determining its fuel quality, and most of the properties were well within ASTM and EN standards.

doi:10.14456/WJST.2015.24