A substantial amount of corn is grown in this country for the purpose of producing ethanol. The value of doing so is debatable for many reasons. Nevertheless, the majority of the corn crop is grown for food. But along with all that corn, there is corn stover. Stover is the dried stalks, leaves, and other plant parts that remain in the field after the corn itself has been harvested. Corn stover is the largest quantity of biomass residue in the United States. Around 250 million tons of it is produced annually and the majority of it is left unused. Some is used for animal feed and other purposes and has monetary value, but much of it goes to waste.
Scientists at Washington State University have developed a way to produce low-cost sugar from stover that can be used to make biofuels and other bioproducts.
Corn stover is an abundant and cheap source of biomass, which holds great potential as a source of energy and valuable chemicals. The challenge is to overcome the high cost of processing stover whose complex structural molecules like cellulose and lignin need to be broken down.
The new process uses potassium hydroxide and ammonium sulfite to convert stover into a sugar. It is a mild-temperature process that allows enzymes to break down the cellulosic polymers in stover into sugar, which can then be fermented into biofuels. The resulting sugar from the process would be cost-competitive with low-cost imported sugars. The researchers estimate that their patent-pending process could produce sugar that could be sold for as low as 28 cents per pound.
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Scientists discover a new way to convert corn waste into low-cost sugar for biofuel
Photo, posted August 30, 2012, courtesy of Idaho National Laboratory Bioenergy Program via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio
