The results presented in this study indicate that in an oxygen-free environment at a temperature between 250 and 550°C, the methylating reagent TMAH directly con­verts algae biomass into the fatty acid methyl esters found in biodiesel. While algae, high in lipid content and rapid in growth, are an ideal biomass for biodiesel produc­tion, we suggest that this direct conversion process can be used with various forms of other types of biomass. For example, soybeans have been treated with TMAH/ methanol and shown to give similar fatty acid methyl esters [15]. This process is also unique among biodiesel conversion technology in that the biomass introduced may be used wet, partially dried, or dried. Removing water from algal biomass is viewed as an important challenge to making conversion to biofuels feasible. The traditional transesterification process, in which sodium hydroxide is used to cata­lyze the reaction, requires the exclusion of water [12, 23]. There is also a require­ment to remove free fatty acids in the transesterification process, mainly because the free fatty acids are converted to fatty acids salts which do not undergo transesterification. Grasset et al. have shown that the TMAH process can convert free fatty acids to their methyl esters [13]. Thus, we expect that removal of free fatty acids from algal oils would not be necessary. This, combined with the fact that com­plete water removal would be unnecessary, suggests that one could streamline any commercial production of biodiesel using our proposed TMAH thermochemolysis methodology.

Although high temperatures of 450°C produce the highest yield of biodiesel, the ideal temperature for this TMAH process is 250°C or lower. Because the residual biomass char is not significantly altered, it is likely to be more useful as a fertilizer than would be a more highly charred product that one obtains at higher reaction temperatures. In addition, maintaining the reactor at a low temperature consumes less energy.

Acknowledgments We thank R. L. Cooper, T. A. Egerton, R. L. Hubbard, R. Mesfioui, and C. L. Wingreen for their help with sample collection and analysis. We thank all of those individuals from various departments at Old Dominion University (ODU) whose research has been invaluable towards this project, especially C. Burbage, A. Gordon, H. Marshall, and A. Stubbins. We also thank the College of Sciences Major Instrumentation Cluster (COSMIC), at ODU for the use of their NMR facility. This work is supported by the Virginia Coastal Energy Research Consortium (VCERC) and funded through the Commonwealth of Virginia.