Monday, April 30, 2007

Production of biodiesel from tung oil

Ji-Yeon Park1, Deog-Keun Kim1, Joon-Pyo Lee1, Soon-Chul Park1, Zhong-Ming Wang2, and Jin-Suk Lee1. (1) Bioenergy Research Center, Korea Institute of Energy Research, 71-2, Jang-dong, Yuseong-gu, Daejeon, 305-343, South Korea, (2) Biomass Energy Center, Guangzhou Institute of Energy Conversion, No.2 Nengyuan Rd, Wushan, Tianhe, Guangzhou, 510640, China

The interest in the use of renewable resources as replacement for petroleum-derived fuels is growing due to high oil price and Kyoto protocol. Among these alternative fuels produced from renewable resources, biodiesel has become a fast growing market during the last years. As the supply of biodiesel increases rapidly, the stable supply of raw materials is becoming an issue because the shortage of raw materials causes the increase of vegetable oil price. Utilization of new raw materials for biodiesel production is needed for costing down the biodiesel price. Tung oil is one of potential alternative materials for biodiesel production which is non-edible. The feasibility of biodiesel production from tung oil was investigated. The acid value of crude tung oil was 8.7 mg KOH/g and its viscosity was 101.0 cps at 40C. Considering its high viscosity, three kinds of processes for biodiesel production were applied. First, the esterification and transesterification processes by acid catalyst showed 71.2 wt% of fatty acid methyl ester (FAME). The purity of tung biodiesel was very low. Second, the esterification process by acid catalyst and the transesterification process by alkali catalyst showed 89.5 wt% of FAME. This process needed the washing step because two different catalysts were used. Third, the neutralization and transesterification processes by alkali catalyst showed 91.0 wt% of FAME. Although there was some loss due to neutralization, the high purity of tung biodiesel was obtained. After the distillation, it would become tung biodiesel over 96.5 wt% of FAME.