Refined Path From Biomass To Biofuel

The challenge of economically converting lignocelluosic biomass into transportation fuels is to develop efficient chemistry that minimizes processing. In a bid to meet that challenge, Jesse Q. Bond, James A. Dumesic, and coworkers at the University of Wisconsin, Madison, have devised an integrated flow-reactor system for converting the versatile biomass-derived feedstock γ-valerolactone into ready-to-use gasoline and jet fuel (Science 2010, 327, 1110). The Wisconsin team’s method improves downstream processing of γ-valerolactone by first using a silica-alumina catalyst to open the ring and decarboxylate aqueous γ-valerolactone to a mixture of butenes and CO₂. The butenes are subsequently strung together by using an amberlyst catalyst to form octenes and higher alkene oligomers with molecular weights and branching that can be selectively formulated as gasoline or jet fuel. The new approach provides several bonuses. It avoids costly precious-metal catalysts and doesn’t require an external source of H₂. And although the process generates CO₂ as a by-product, the reactor design allows the CO₂ to be trapped as a relatively pure, pressurized stream that could be readily sequestered or used to make methanol or polycarbonates.