Transesterification of waste chicken fats for synthesizing biodiesel by CaO as heterogeneous base catalyst

High consumption of chicken in Indonesia leads to a considerable amount of chicken skin as a waste. The utilization of this chicken skins as possible biodiesel feedstock was therefore investigated. The transestrification between this chicken fats and methanol was conducted using calcium oxide as solid catalyst. The variables affecting the yield of biodiesel during transesterification, such molar ratio of methanol to oil, reaction time, reaction temperature, catalyst concentration ware investigated. With 1 % catalyst, when the transesterification was carried out at molar ratio of methanol to oil of 6∶1, reaction time of 1.5 hours, reaction temperature of 50 °C, yield of 75.4% was achieved. The fuels properties, namely, kinematic viscosity, specific gravity, flash point, cetane number, water content and iodine number are found within the limit of Indonesian National standard for Biodiesel.