University of Georgia researchers have developed a new process to increase the yield of ethanol from readily available non-food crops, such as bermudagrass, switchgrass and napiergrass.
Joy Peterson, professor of microbiology and chair of UGA’s Bioenergy Task Force, said: ‘Producing ethanol from renewable biomass sources such as grasses is desirable because they are potentially available in large quantities. And optimising the breakdown of the plant fibres is critical to production of liquid transportation fuel via fermentation.’
Peterson developed the new process with former UGA microbiology student Sarah Kate Brandon, and Mark Eiteman, professor of biological and agricultural engineering.
It features a fast, mild, acid-free pretreatment process that increases by at least 10 times the amount of simple sugars released from inexpensive biomass for conversion to ethanol.
Currently, woody biomass requires soaking under high pressure and temperature in expensive, environmentally aggressive bases or acids before it is subjected to enzymes that digest it, producing simple sugars.
The harsh pretreatment solutions subsequently must be removed and disposed of safely. They also cause formation of side products that can slow down the conversion of the sugars into ethanol.
In contrast, the environmentally friendly UGA technology eliminates the expense of harsh pretreatment chemicals and their disposal, and the formation of side products is minimal.
The process is available for licensing from the University of Georgia Research Foundation, which has filed a patent application for it.