Cellulosic Biofuels

Cellulosic Biofuels

One scientist’s quest for cellulosic biofuels

One scientist’s quest for cellulosic biofuels

April 9, 2008

George Huber of the University of Massachusetts Amherst has received a $400,000 CAREER grant from the National Science Foundation to pursue his revolutionary new method for making biofuels, or “green gasoline,” from wood or grasses, a process that would be much less expensive than conventional gasoline or ethanol made from corn.

Results of Huber’s research were published in the April 2008 issue of ChemSusChem, a publication devoted to environmentally-sound chemistry.

“We’ve proven this method on a small scale in the lab,” says Huber, a professor of chemical engineering. “But we need to make further improvements and prove it on a large scale before it’s going to be economically viable.”

Huber is a nationally recognized expert on biofuels, which are sustainable fuels made from plant materials. In June 2007, he chaired a workshop in Washington, D.C., for the National Science Foundation and the U. S. Department of Energy titled “Breaking the Chemical & Engineering Barriers to Lignocellulosic Biofuels,” which was attended by 71 top experts from academia, industry and governmental agencies.

Huber’s method is for making biofuels from cellulose, the non-edible portion of plant biomass and a major component of grasses and wood. At $10 to $30 per barrel of oil energy equivalent, cellulosic biomass is significantly cheaper than crude oil. The U.S. could potentially produce 1.3 billion dry tons of cellulosic biomass per year, which has the energy content of four billion barrels of crude oil. That’s more than half of the seven billion barrels of crude oil consumed in our country each year. What’s more, biomass as an energy crop could increase the national farm income by $3 to $6 billion per year.

Huber is addressing the lack of an economical process for converting cellulose into liquid biofuels, which is the main roadblock for their mass production. Every conventional conversion method takes several steps, with each step making the whole process more expensive and less feasible. For example, ethanol production from cellulosic biomass currently involves multiple steps, including pretreatment, enzymatic or acid hydrolysis, fermentation, and distillation. Other processes for making biofuels have been hamstrung by similar multi-step methods.

Huber has come up with a technique for producing his “green gasoline” from biomass in one simple step by placing solid biomass feedstocks such as wood in a reactor, which is basically a high-tech still for thermal conversion of feedstock to gasoline. He heats the feedstock by a technique known as catalytic fast pyrolysis, which means the rapid heating of the biomass to between 400 and 600 degrees centigrade, followed by quick cooling. By adding zeolite catalysts to this process, gasoline range hydrocarbons can be directly produced from cellulose within sixty seconds.

“This is a big improvement because it’s all done in one single step, instead of several stages,” explains Huber. “Also, because of the high temperatures we use in the process, the residence time in our reactor is two to 60 seconds. With cellulosic ethanol, your residence time is five to ten days, which means you have to have a huge reactor costing much more money. So we estimate that building a facility to use our process would be much less expensive.”

Using the current cost of wood in Massachusetts, which is $40 per dry ton, as an example of the feedstock he can use in this process, Huber estimates that a gallon of green gasoline can be produced with his method for between $1 and $1.70, depending on how much he can improve the catalytic conversion in his process through standard engineering techniques.

Huber has already demonstrated that this process will work on a small scale in his lab. Now he has to design a reactor and catalysts that are specifically geared for his process. Huber just received a $30,000 grant from the UMass Amherst Office of Commercial Ventures and Intellectual Property, as funded by the UMass president’s office, to develop a prototype reactor to demonstrate green gasoline production on a large scale.

Huber has been working with three other professors at UMass Amherst including Phillip R. Westmoreland, a chemical engineer and expert on fast pyrolisis who has been helping to design the reactor, and William C. Conner, a chemical engineer with expertise in zeolite catalysts. The third researcher is Scott Auerbach, a theoretical chemist from the UMass Amherst chemistry department.

Breaking the Chemical and Engineering Barriers to Lignocellulosic Biofuels:


SOURCE: Univ. of Massachusetts at Amherst
[Submitted by Hemp4Fuel]

Tennessee Breaks Ground on Cellulosic Ethanol Pilot Plant


10/15/2008 2:24:59 PM
Tennessee Breaks Ground on Cellulosic Ethanol Pilot Plant

Charles Johnson, Farm Journal National Editor

With a crowd of dignitaries, farmers, media and university representatives on hand, Tennessee broke ground on its long-awaited pilot cellulosic ethanol plant Oct. 14.

Located in an industrial park at Vonore, Tenn., 35 miles south of Knoxville, the plant begins with $40.7 million in state money for its construction. The project, using switchgrass as a feedstock, will produce just 250,000 gallons of ethanol a year beginning in fall 2009 but will be the key research facility in the state’s efforts to birth its biofuels industry.

Tennessee Gov. Phil Bredesen speaks at the cellulosic ethanol plant ground-breaking ceremony. (Photos: Charles Johnson)

Called Genera Energy, the project is a partnership between the University of Tennessee and DuPont Danisco Cellulosic Ethanol LLC, a joint venture formed this year by DuPont and Genencor to commercialize cellulosic ethanol.

Sixteen farmers within a 50-mile radius of the site planted 723 acres of switchgrass under a state-funded program this year so the facility will have feedstock when operations begin. The farmer program will add up to 2,000 additional acres next spring and still more acreage the following year.

“It’s a great opportunity and gives us insight into a new crop and the business of agriculture. I’d love to see the U.S. independent of foreign oil and am thrilled that agriculture can be part of it. Just imagine what our economy might be if we were investing the billions of dollars sent overseas for fuel right here in our local communities,” says David Richesin, Philadelphia, Tenn., one of the cooperating farmers, who spoke at the groundbreaking.

“The plant and partnership will do an awful lot for this state’s future, in meeting energy demands and, at the same time, supporting agriculture and rural areas. We really have a double win,” says Gov. Phil Bredesen.

“When it comes to facing the challenges of the future, Tennessee isn’t just talking the talk about clean energy technology. We’re walking the walk, rolling up our sleeves and getting to work. Tough economic times like this are when it’s.most important to make investments for the future that down the line will result in jobs,” Bredesen says.

Bredesen envisions a future with ten or more cellulosic ethanol plants across the state, providing thousands of jobs along with increased economic opportunities for farmers.

“This plant has the potential to open all kinds of doors for us. It represents a bold step. To continue to take advantage of it we need to continue to take bold steps. We in Tennessee have the opportunity to take real leadership in the area of alternative fuels. We don’t need to stop with the pilot plant. We need to be bold,” Bredesen says.

Newly developed technology puts the pilot plant on, “an accelerated schedule,” says Joe Skurla, DuPont Danisco’s president and chief executive officer.

“At DuPont Danisco, we’re taking a global view of this emerging industry. Tennessee has leveraged its natural advantage into a foundation for the future. The farming community knows better than anyone that this country has the ability to produce all the food, all the fiber and all the fuel we need. Together we will show the world a way to a bio-based future, and it all begins here,” Skurla says.

“Thanks to the University of Tennessee Biofuels Initiative for supporting the grower system in which switchgrass production is already underway. At DuPont Danisco, we have the technology package that is going to win in the marketplace. We are ready to scale up. Partnerships are very necessary, and Tennessee is the perfect partner for us,” Skurla says.

The switchgrass project has promise to help Tennessee farmers, says Lacy Upchurch, president of the Tennessee Farm Bureau Federation.

“Anytime you develop a new energy crop that can be grown on more marginal land and is a perennial, too, requiring fewer inputs, that’s good. If we can develop the process and make a success of turning it into biofuel of some kind, it’ll be a tremendous boost for agriculture. A lot of our farmers are kind of conservative, but they will step in if there’s a good sound market for switchgrass,” Upchurch says.

Pictured are some of the 16 farm families cooperating with the University of Tennessee’s switchgrass project.

You can e-mail Charles Johnson at cjohnson@farmjournal.com.

© 2008 AgWeb.com. All Rights Reserved.

[Submitted by KEVswr]

Promising Biofuel Made From Commercial Yeasts Upgraded With A New Enzyme


Adapted from materials provided by Goethe University Frankfurt, via EurekAlert!, a service of AAAS.

By Science Daily staff writer

Eckhard Boles, co-founder of the Swiss biofuel company Butalco GmbH and a professor at Goethe-University in Frankfurt, Germany, has discovered a new enzyme which teaches yeast cells to ferment xylose into ethanol. Xylose is an unused waste sugar in the cellulosic ethanol production process. The researchers have recently filed a patent application for their process.

In industrial fermentation processes, the yeast Saccharomyces cerevisiae is commonly used for ethanol production. Current bioethanol production technologies can use only parts of the plants, namely the storage sugars, like glucose, sucrose or starch. However, this technology is in competition with food and feed production. Eckhard Boles, co-founder of the Swiss biofuel company Butalco GmbH and a professor at Goethe-University in Frankfurt, Germany, has therefore searched for ways of teaching the microorganisms to convert waste sugars, xylose and arabinose, into ethanol.

Now, Boles and his colleagues have succeeded in genetically modifying industrial yeast strains, thus producing ethanol from xylose in a single step. Having already succeeded in transforming arabinose into ethanol by genetically modified yeast strains, Boles and his team have now found an efficient way to convert most of the plants energy into biofuel.

“Up to now scientists considered it as unpromising to equip yeast with a bacterial enzyme capable of converting xylose”, Boles explains, “because all attempts had failed”. But he and his team continued trying by exploring the enormous amounts of information in current genetic databases. Step by step they took 12 enzymes from different bacterial organisms and inserted the enzymes into yeast cells. Finally they discovered a new enzyme that even worked in yeast cells from a commercial ethanol plant. In contrast to current cellulosic ethanol technologies the new enzyme can convert xylose in a single step and is not inhibited by other chemical compounds normally present within the yeast cells. The researchers have recently filed a patent application for their process. “This is a break-through in the commercialisation of cellulosic ethanol”, comments Boles.

Boles says: “We have successfully demonstrated the conversion of waste sugars into ethanol. However, ethanol is not the best renewable biofuel. There are other alcohols with many more promising properties.” Together with his company, Butalco GmbH, Boles is now constructing yeast strains to convert plant waste materials into biobutanol, which is being seen as a more superior alternative fuel than ethanol due to its more favourable chemical and physical properties.

[Submitted by hempistry]

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