IN SITU BIODIESEL PRODUCTION FROM RESIDUAL OIL RECOVERED FROM SPENT BLEACHING EARTH

Abstract

Currently, semi-refined and refined vegetable are the predominant feedstock used in biodiesel production. However, the relatively high cost hinder the development of biodiesel industry due to the resulting fuels is unable to compete with petroleum-derived fuel. Spent bleaching earth, a waste material from vegetable oil processing, can be used to recover the oil. The potential of using residual oil in spent bleaching earth as a lipid feedstock for biodiesel production was investigated. In situ process is used to convert residual oil in spent bleaching earth to biodiesel. The objectives of this study was to investigate the effects of different types of catalyst, different ratio of methanol to spent bleaching earth and ratio of hexane to methanol in the production of biodiesel. Spent bleaching earth was mixed with methanol in which sulfuric acid or sodium hydroxide had been and the mixture was heated at 75oC under reflux for 24 hours. The weight of biodiesel was determined and it was analyzed using gas chromatography mass spectrometry. From the results, the highest yield of biodiesel was obtained if sodium hydroxide was used with methanol to spent bleaching earth ratio of 200ml:50 gram and hexane to methanol ratio of 120ml:200ml