Purdue Researchers Launch Innovative Biomass Renewable Energy Company

Mahdi Abu-Omar

Purdue University researchers are launching a company focusing on an innovative process that could revolutionize how lignocellulosic biomass is used to make biofuels and other bio-based products and chemicals.

Spero Energy Inc., which is based in the Purdue Research Park, will be led by Mahdi Abu-Omar, the R.B. Wetherill Professor of Chemistry and Chemical Engineering and associate director of Purdue's Center for Direct Catalytic Conversion of Biomass to Biofuels (C3Bio).

"Spero Energy's transformative technology of making high-value chemical products from lignin with simultaneous production of lignin-free cellulose in one step, is a significant step toward our nation's pursuit of renewable energy sources," said Abu-Omar, division head of inorganic chemistry and associate director of C3Bio. "The lignin-derived Spero products also are expected to provide this new company an entry into the aromatic specialty chemicals market."

Current biorefinery processes for producing cellulosic ethanol make use of the carbohydrates in the biomass. The lignin, accounting for more than 35 percent of the carbon in biomass, is often used in low-value applications such as heat generation.

Spero's technology portfolio, based on research efforts at C3Bio, centers on novel catalytic processes for converting lignin in wood biomass and waste to liquid chemical products. These chemicals have applications in flavoring and fragrance in addition to high-octane fuels and high-value materials, Abu-Omar said.

The process developed by Spero - its name means "hope" in Latin - produces lignin-free cellulose that can be easily converted into fermentable sugars and sugar-derived, high-value chemicals. It focuses on the delignification of mechanically milled and shredded wood with lignin conversion to methoxypropylphenols with a bifunctional catalyst under mild thermal conditions.

Phenols, which currently are manufactured from petroleum feedstock through multistep processes, are high-value fragrance and flavor compounds.

Current biofuel production is a multistep process, with carbohydrates separated from lignin in a pretreatment process, generally using acid and high temperatures.

For ethanol production, enzymes break down plant material carbohydrates into sugars, which are fermented using yeast. The yeast, using the sugars as food, creates ethanol.

Lignin, however, acts as a physical barrier in plant cell walls, making it difficult for enzymes to break down the biomass, and a chemical barrier by poisoning the enzymes. Without expensive pretreatment, the enzymes get to less than 20 percent of the biomass sugars.

Basudeb Saha, an associate research scientist at Purdue, will serve as chief technology officer of the new company, and postdoctoral researcher Trenton Parsell, with doctoral students Ian Klein and Barron Hewetson, are part of Spero's technical team. Agricultural and biological engineering professor Nathan Mosier and chemical engineering professor Fabio Ribeiro are scientific advisers.

Spero is a spinoff of efforts by Purdue researchers working on the U.S. Department of Energy-funded C3Bio project at Purdue. Affiliated with Discovery Park's Energy Center and the Bindley Bioscience Center, C3Bio also is investigating how to produce fuels that closely resemble gasoline in terms of their molecular makeup and energy density.

"We're excited about how our DOE-funded C3Bio team at Purdue is advancing this high-risk, high-reward research effort," said biological sciences professor Maureen McCann, director of C3Bio and the Purdue Energy Center. "We believe we are having a meaningful, broader impact on the overall economy and the pursuit of viable renewable energy sources through patented technologies and processes and startup companies such as Spero Energy."

Since its 2009 launch through a $20 million grant from the DOE, C3Bio and its team of researchers led by McCann have aimed at using thermal and chemical catalysts to create biofuels that utilize more of a plant's carbon.

The C3Bio team hopes to engineer catalysts or catalytic sites into plants and use heat or chemical catalysts to convert the biomass into fuel directly, without the need for enzymes, yeasts or other microbes. In addition, five patent applications have been filed in connection with the research generated through C3Bio.

The five-year project also has had additional impacts. C3Bio has created more than 20 jobs for students, postdoctoral researchers and professional staff in Indiana and another eight jobs at partner institutions. McCann also serves as director of the Purdue Energy Center.

Joining Purdue as partners of C3Bio are the National Renewable Energy Laboratory, University of Tennessee, Northeastern University and Argonne National Laboratory.

Abu-Omar, who came to Purdue in 2003 from the University of California at Los Angeles, has published more than 100 original research papers and mentored 25 doctoral students and 10 postdoctoral fellows. He and his research group are developing catalysts that transform renewable resources such as biomass to hydrocarbon fuels and high-value chemicals.

A fellow of the American Association for the Advancement of Science, Abu-Omar won the JPP Young Investigator Award from the Society of Porphyrins and Phtalocyanines and was a senior Fulbright Fellow. He also was a University Faculty Scholar and won the College of Science Interdisciplinary Award in 2010.