Current approaches for the production of cellulosic ethanol requires a multi-step process that involves pre-treatment of the biomass prior to its enzymatic hydrolysis to provide the C5 and C6 sugars for subsequent fermentation to ethanol (or butanol). SunOpta provides pre-treatment solutions, and, in partnership with other companies—such as Celunol—cellulosic biofuel production facilities.

The combination of SunOpta and Celunol process technologies will lead to a very competitive solution for producing cellulosic ethanol from various biomass substrates. We are excited to be working with Celunol on the first commercial cellulosic ethanol plant in the United States and look forward to the massive grow out in this market.

—Murray Burke, VP and General Manager, SunOpta BioProcess Group

In June, SunOpta announced the sale of a cellulosic ethanol demonstration facility to China Resources Alcohol Corporation (CRAC) and a Joint Development Agreement with CRAC and Novozymes for the development of cellulosic ethanol in the People’s Republic of China. (Earlier post.)

SunOpta is also supplying its steam explosion equipment and process technology to a subsidiary of Abengoa for its commercial production facility that converts cereal straw into ethanol. (Earlier post.)

Celunol is a privately held company headquartered in Dedham, Massachusetts moving rapidly to commercialize its proprietary technology for producing ethanol from a wide array of cellulosic biomass feedstocks, including bagasse, agricultural waste, wood products and dedicated energy crops.

The key element of Celunol’s technology is genetically engineered Escherichia coli bacteria that can ferment both C6 (hexose) and C5 (pentose) sugars present in cellulosic biomass. (Numerous research efforts around the world are tackling the same problem using different modified organisms such as Zymomonas, Saccharomyces, Lactobacillus, xylose-assimilating yeasts and Clostridium in addition to E. coli.)

E. coli ferments a range of sugars: arabinose, glucose, mannose and xylose. However, wild strains produce a range of fermentation products, but little ethanol. A recombinant E. coli for converting pentose sugars to ethanol was first developed in 1987.

Problems with the bacteria include the pH range for fermentation and the need to withstand the harsh production environment.

Celunol operates a laboratory at the Sid Martin Biotechnology Development Incubator of the University of Florida—from which Celunol has licensed technology—and a research laboratory and pilot plant in Jennings, Louisiana. Celunol has also benefited from targeted sponsored research at the University of Florida, Dartmouth College, Auburn University, the University of Colorado and the University of California (Davis).

The company is currently completing an expansion of the Jennings pilot facility and is moving forward to construct a demonstration plant based on its technology later this year. Celunol aspires to develop and build a portfolio of ethanol facilities in the US and abroad. Shareholders in the company include Braemar Energy Ventures, Charles River Ventures, Khosla Ventures, and Rho Capital Partners.

Resources:

• Cellulosic Ethanol: Past, Present and Future (SunOpta presentation)

• Development of New Biocatalysts for the Conversion of Lignocellulose to Ethanol (USDA Fermentation Biology Research)

• Metabolic Engineering for Fuels and Chemicals (University of Florida)