Transesterification of Low FFA Waste Vegetable Oil using Homogeneous Base Catalyst for Biodiesel Production: Optimization, Kinetics and Product Stability

Abstract

The most common method of biodiesel production is base catalyzed transesterification where alkaline materials, such as potassium hydroxide, are used as a catalyst. This paper presents a study of factors affecting biodiesel production from low free fatty acids (FFA) content waste vegetable oil through base catalyzed transesterification as well as the optimum reaction conditions. The optimum conditions were found to be a time of 60 min, catalyst loading of 1% of oil mass, mixing speed of 400 rpm and temperature of 65 °C. It also introduces a kinetic study of this reaction to determine the best model to fit the experimental data. First order model was found to be the best one to fit the early reaction stages while the second order model was the best to describe reaction kinetics in later stages. The stability of produced biodiesel was studied through determination of acid value and viscosity of stored biodiesel along three months.