Huber says the process could work with any woody biomass, ranging from trees to switchgrass to the inedible portion of today's food crops. He says there is enough raw material in the United States to supply the energy equal to 60 percent of the nation's oil. The advantage of this process is that this fuel would not be a radical departure from fuels used today. Huber says, "Our goal is to make products that fit seamlessly into the existing infrastructure and to the existing markets."
He notes that biomass could create an oil barrel's worth of energy for between $10 and $30. With crude oil prices well over $100 per barrel, successful large-scale production would be good news for an energy hungry planet. But first, Huber says, "The challenge is to design an efficient process to take it and efficiently convert it to a liquid fuel."
Huber is enthusiastic about biofuels, noting, "The only source we have of a sustainable liquid fuel is plant biomass." He rejects as a "major myth" the idea that biofuel generation is driving food prices higher. He points to the current price of oil, noting, "It causes your fertilizer (prices) to go up. It causes your transportation costs to go up and that, in turn, cause food prices to go up."
Right now Huber and his team, graduate students Torren Carlson and Tushar Vispute, have created small test batches and are trying to improve that process before attempting any larger production. Writing in "Chemistry & Sustainability, Energy & Materials," the researchers explain how their process worked. They heat the cellulose to more than 1100 degrees Fahrenheit (600 degrees Celsius) in the presence of a catalyst. Catalysts speed reactions without actually being part of the reaction. Huber says the material then starts "thermally decomposing." The vapors from that thermal decomposition cool into the liquid that is the fuel.
"The whole beauty of this process is the simplicity," explains Huber. "One of the challenges in making a biofuel…is the â€˜residence time' or the time your molecules spend in the reactor." Current biofuel plants have a "residence time" of five to ten days. Huber notes the "residence time" for this new process is "between two to 120 seconds." Huber says that means a production plant could be much smaller than current biofuel plants.
This research was published online in advance of print on April 2, 2008 by the journal "Chemistry & Sustainability, Energy & Materials" and was funded by the National Science Foundation.