Materials for Energy, Efficiency and Sustainability: TechConnect Briefs 2015Materials for Energy, Efficiency and Sustainability TechConnect Briefs 2015

Materials for Oil, Gas & Biofuels Chapter 4

In situ transesterification of wet microalgae under acid catalysts

J.W. Lee, B. Kim, H. Im
Korea Advanced Institute of Science and Technology, Korea

pp. 164 - 167

Keywords: in situ transesterification, wet microalgae, biodiesel, acid catalysts

Microalgae can be categorized to be the third generation of promising biofuel resources and can utilize carbon dioxide from flue gas as a nutrient source and accumulate lipids inside cells. They grow faster than any other plants and can be cultivated even in race ponds of waste water treatments. Despite the high level of microalgal lipids, the production of biodiesel from microalgal cells still lacks in making feasible economy due to the production cost. One of energy intensive processes of biodiesel production is concentrating and drying wet algal cells to facilitate the subsequent lipid extraction. The cost for this process occupies 20-30% of the total cost of biodiesel production. To this end, this talk addresses a reliable in situ transesterification process which integrates lipid extraction from wet microalgae, and its conversion to biodiesel without having a drying process. The process enables one-step production of biodiesel by heating the mixture of wet Nannochloropsis gaditana cells with co-solvent, ethanol, and acid catalysts in one pot. Effects of reaction parameters (temperature, catalyst volume, co-solvent volume) on biodiesel yields will be investigated under various conditions. It will be shown that the fatty acid methyl or ethyl ester yield of 90-100% is achieved.