Cheaper, Greener Solvent for Pretreatment of Miscanthus Biomass

University of Illinois scientists have demonstrated an environmental and economical way of pretreating biomass from the grass Miscanthus for biofuel production with the use of a switchable and recoverable solvent.

Conventional pretreatment process of lignocellulosic biomass, such as grass and wood, uses high temperature and harsh chemical conditions to deconstruct the complex lignocellulose before they can be fermented into ethanol. The current study by University of Illinois researchers used the solvent called butadiene sulfone for pretreatment. Butadiene sulfone can switch chemically to another form at relatively lower temperature, forming an acid in the presence of water that can break down complex sugars in pretreated Miscanthus biomass. Aside from its unique switching ability, butadiene sulfone can reform from its derivatives after decomposition, allowing recovery for potential re-use in pretreatment process.

The researchers found that the acid product could break down up to 91 percent of the complex xylan sugars and butadiene sulfone could degrade about 58 percent of the tough lignin polymer that impedes ethanol production while preserving 90 to 99 percent of cellulose. The findings were published in the journal Green Chemistry.