Cellulosic Ethanol : Process

Cellulosic Ethanol Production Technology

Verenium has Developed the Key Technology to Enable the Economic Conversion of Biomass to Ethanol

In 1995, Verenium, then Celunol, secured an exclusive license to commercialize proprietary cellulosic ethanol technology developed at the University of Florida. Working with the University and other academic and industry sources, including Dartmouth, Auburn, The University of Colorado, and the University of California at Davis, Verenium has continued to develop its unique technology to release the full sugar potential of cellulosic biomass.

Today, Verenium continues as an R&D leader in the cellulosic ethanol field. The company operates a laboratory in San Diego, California, as well as a research laboratory at its pilot plant in Jennings, Louisiana.

Converting Plant Sugar to Cellulosic Ethanol

The sugar in cellulosic biomass is locked up in the form of cellulose and hemicellulose. Cellulose contains glucose, the same type of sugar - six-carbon (C6) sugar - that is found in cornstarch and that can be fermented to ethanol using conventional yeasts. However, hemicellulose contains mainly non-glucose sugars-five-carbon (C5) sugars. Conventional yeasts cannot ferment most non-glucose sugars to ethanol with commercially acceptable yields.

Verenium’s technology enables almost complete conversion of all the sugars found in cellulosic biomass. This efficiency advantage, combined with the low input cost of cellulosic biomass, results in superior economics in the production of ethanol.

Scientific breakthroughs by Verenium are enabling the economic production of ethanol from a renewable and inexpensive energy source - plant waste materials

There are at least five advantages to using cellulosic biomass as the raw material for biofuels: (1) use of non-food crops, (2) relatively low feedstock cost, (3) use of marginal lands for feedstock growth, (4) beneficial net energy balance, and (5) less fertilizer and water usage.

Biomass is a complex material composed of cellulose (30-50%), hemicellulose (20-40%), and lignin (15-30%). The exact composition varies from plant to plant. Since it is found in nearly all plant life, cellulose is the most abundant molecule on earth. Like the starch found in corn kernals, cellulose is a polymer of the sugar glucose. It forms part of the cell wall and is designed to contribute to the structural integrity of the plant. Hemicellulose is a more random and amorphous structure of connected sugars.

There are several technical and economic challenges associated with the large-scale production of ethanol from cellulosic biomass, including collection and transport of the biomass raw material, preprocessing or pretreatment, dilute acid hydrolysis and enzymatic conversion of pretreated plant material to sugars, and fermentation of a mixed sugar stream.

Verenium has made advances in each of these areas over the past several years, greatly improving the likelihood that cellulosic ethanol will become a commercial reality in the very near future. In particular, we are using proprietary and unique microorganisms, called ethanologens, to ferment cellulose and hemicellulose from multiple feedstocks into ethanol.