Advanced (Liquid) Biofuels

The bioconversion of lignocellulosic biomass to biofuels largely began in response to the Oil Crisis of 1973. Since then, ethanol has been the prevailing biofuel of choice due to its octane enhancement properties (when blended with gasoline) and its ease of production in large volumes. Ethanol, however, is miscible with water and is known to create complications/damage when combusted in high concentrations in internal combustion engines. In addition, ethanol has an energy content approximately two-thirds that of gasoline.

Recent research has attempted to steer away from ethanol as a biofuel and to replace it with advanced biofuels such as butanol or biomass-derived hydrocarbons. These fuels are inherently hydrophobic and have energy densities which are comparable to gasoline. Unfortunately, advanced biofuels are capital intensive even at the laboratory scale. A biorefinery, which seeks to create multiple products from a single feedstock, is one avenue presently being explored for the co-generation of high-value biobased products that can offset the cost of advanced biofuel production. In particular, green processing (a technique used to fractionate crude feedstock into a solid and liquid substrate) has been the focus of efforts in (sub)tropical geographies like Hawaii. Below you will find links to various topics related to the research presently under investigation at the University of Hawaii at Manoa.