Cellulosic Biofuels

 Researchers: Trevor Zuroff

The need for a sustainable, renewable source of transportation fuels has been recognized for a long time; however, the availability of inexpensive oil has largely obscured the urgency for its development. Recent political and economic events have highlighted the fragility of our dependence on foreign oil and reinvigorated a longer-term perspective on the need to provide a sustainable source of domestically-produced transportation fuel. Many fuel production alternatives are being proposed, ranging from purely thermochemical, to hybrid and to entirely biological production. As potential concedes to process performance, economics will sort out the best production options.

Figure 1. A small piece of paper with the word "Biofuel" written on it in a Clostridium phytofermentans culture 
degrading over time. One of the main products of C. phytofermentans cellulose hydrolysis and fermentation is ethanol.

This project focuses on the biological route to liquid fuels with a strong emphasis on cost reduction at the level of bioreactor design to provide a realistic comparison to alternative strategies. Though there are biosynthetic routes to biobutanol and branched alcohols, only for ethanol have organisms been discovered that can directly produce fuel from the cellulose substrate (Lynd et al., 2002). Within this context, this project seeks to develop the most cost-efficient production system because the economic demands of biofuels production will invariably dictate that the organism meet these processing requirements. A combination of many considerations favors production of fuels in a trickle-bed fermentation process with an organism capable of direct fermentation of the cellulosic biomass to biofuel such as Clostridium phytofermentans.