Turning corn fiber into ethanol

Tony Pometto held up a laboratory flask swimming with little balls of mold. This, said the Iowa State University professor of food science and human nutrition, is the kind of fungus that Iowa State researchers have used to successfully convert corn fiber that's typically used for animal feed into ethanol.

And that could boost ethanol production by about 4 percent or 160 million gallons a year, said Hans van Leeuwen, an Iowa State professor of civil, construction and environmental engineering.

"I believe this is a breakthrough," said van Leeuwen, the leader of the research project. "But I also want to caution that we need to do a lot more research."

So far, the researchers have demonstrated they have a process that can convert corn fiber -- a byproduct of the wet milling process that produces corn syrup -- into fuel-grade ethanol on a very small scale. With additional research they'd like to at least double the amount of ethanol their process produces. They would like to try it on a larger, pilot scale. And they would like to try it on other byproducts of corn processing.

Van Leeuwen said the next step is to see how the process works on distillers dried grains, a byproduct of the dry milling process that's typically used to convert corn kernels into ethanol.

The research project is supported by a $150,000 grant from the U.S. Department of Agriculture through the Iowa Biotechnology Byproducts Consortium, $130,000 from the Iowa Energy Center and materials from the ethanol industry. In addition to van Leeuwen and Pometto, the research team includes Samir Khanal, an Iowa State research assistant professor, and Iowa State graduate students Mary Rasmussen and Prachand Shrestha.

And let's not forget the mold.

The mold produces enzymes that break down corn fiber into the simple sugars that are fermented into ethanol. And that's not an easy thing to do.

Pometto said corn fiber -- which, like all lignocellulose, forms the structure of a plant's cell walls -- is very tough stuff.

"There's a reason it's very hard to degrade," he said. "It needs to be tough because nature wants to have growing plants. Without growing plants we'd all be dead."

The researchers' techniques for working with mold and corn fiber to produce ethanol are now being reviewed for a possible patent. And van Leeuwen thinks their discovery has lots of potential for the ethanol industry.

After all, van Leeuwen said, "We're not using harsh chemicals, high temperatures, high pressure or expensive enzymes to do this."

Source: Iowa State University

Related stories:

Turning Waste Material into Ethanol
(PhysOrg.com) -- Say the word “biofuels” and most people think of grain ethanol and biodiesel. But there’s another, older technology called gasification that’s getting a new look from researchers at the U.S. Department of Energy’s Ames Laboratory and Iowa State University. By combining gasification with high-tech nanoscale porous catalysts, they hope to create ethanol from a wide range of biomass, including distiller’s grain left over from ethanol production, corn stover from the field, grass, wood pulp, animal waste, and garbage.
Researchers study ground cover to reduce impact of biomass harvest
Ground cover may be one workable method to reduce the effects of erosion that future biomass harvests are predicted to bring. Iowa State University researchers are looking at ways to use ground cover, a living grass planted between the rows of corn, in production farming.
Researchers use fungus to improve corn-to-ethanol process
Growing a fungus in some of the leftovers from ethanol production can save energy, recycle more water and improve the livestock feed that’s a co-product of fuel production, according to a team of researchers from Iowa State University and the University of Hawai’i.
Researchers developing system to efficiently convert biomass to ethanol
Iowa State University researchers are developing an integrated system of thermochemical and catalytic technologies to efficiently produce ethanol from plant biomass.
US rush to produce corn-based ethanol will worsen 'dead zone' in Gulf of Mexico
The U.S. government’s rush to produce corn-based ethanol as a fuel alternative will worsen pollution in the Gulf of Mexico, increasing a “Dead Zone” that kills fish and aquatic life, according to University of British Columbia researcher Simon Donner.
Earlier plantings underlie yield gains in northern corn belt
U.S. farmers plant corn much earlier today than ever before and it seems to be paying off, at least in the north. Earlier plantings could account for up to half of the yield gains seen in some parts of the northern Corn Belt since the late 1970s, a new study has found.
Scientists unveil draft sequence of corn genome
A team of scientists led by Washington University in St. Louis has begun to unlock the genetic secrets of corn, a crop vital to U.S. agriculture. The researchers have completed a working draft of the corn genome, an accomplishment that should accelerate efforts to develop better crop varieties to meet society's growing demands for food, livestock feed and fuel.
ISU scientist researches ways to squeeze two fuels from one kernel of corn
Getting ethanol from a corn kernel has changed the way the country looks at a corn field. Now, that view might change again.

News discussion:

Technology news