Transesterification of triglycerides and esterification of fatty acids are both exothermic reactions but their heat capacity is small. In alkali catalyst process, energy to increase the system to 60-70oC, energy for a methanol, and energy for the whole reaction process are essential. Futhermore, additional enrgy is required after the reaction for purifying the glycerin as a by-product. In the biodiesel production with 2.2 kg/s (70,000 t/year) capacity, energy efficiency is reported to be 62% on higher heating value basis.

4.7.4 Status-quo of the technology

Biodiesel production has been commercially developed in Europe and North America, and their production is mainly based on alkali catalyst method. However, for the low-grade waste

oils, a combined process with acid catalyst has been developed with their own non-disclosed technologies. Due to the limited raw materials in Japan, new development of the technology will be expected to handle the low-grade waste oils to be converted into high-quality biodiesel.

Further information

Ban, K.; Kaieda, M.; Matsumoto, T.; Kondo, A.; Fukuda, H. Whole cell biocatalyst for biodiesel fuel production utilizing rhizopus oryzae cells immobilized within Biomass Support Particles, Biochem Eng J 8, 39-43 (2001)

Boocock D. G. Biodiesel fuel from waste fats and oils: A process for converting fatty acids and triglycerides, Proc. of Kyoto Univ Int’l Symp. on Post-Petrofuels in the 21st Century, Prospects in the Future of Biomass Energy, Montreal, Canada, 171-177 (2002)

Kusdiana, D.; Saka, S. Two-step preparation for catalyst-free biodiesel fuel production; hydrolysis and methyl esterification, Appl Biochem. Biotechnol, 115, 781-791 (2004)

Mittelbach, M.; Remschmidt, C. Biodiesel, The comprehensive handbook, Boersedruck Ges. m. b.H, Vienna, Austria, 1-332 (2004)

Saka, S. “All about Biodiesel”, IPC Publisher, 2006, pp.1-461 (in Japanese)

Sekiguchi, S. in “Biomass Handbook”, Japan Institute of Energy Ed., Ohm-sha, 2002, pp.138-143 (in Japanese)