UC Riverside researchers streamline process to make 2G ethanol competitive with 1G

In California, University of California-Riverside researchers have developed a streamlined process that could finally make the ethanol production cost from abundant second-generation plant wastes competitive with first-generation ethanol made from sugars.

UCR researchers have identified a way to improve the yield of ethanol from biomass. It involves direct fermentation of solid biomass, moving straight from pretreatment to a single process that both releases sugars and ferments them into ethanol. This streamlined strategy, called simultaneous saccharification and fermentation, or SSF, makes for a simpler process, and potentially reduces the enzymes needed to digest the solid material.

Ethanol yields from SSF strategies in the past have been too low, with a limited concentration of ethanol. Enter the new pretreatment method invented by the UCR researchers, called CELF, short for co-solvent enhanced lignocellulosic fractionation. Using CELF, researchers can pretreat biomass such as corn stover and produce a sugar-rich and highly digestible biomass that—using the SSF strategy—can be converted to ethanol while also maintaining high ethanol yields.

In fact, the UCR team achieved maximum ethanol concentrations similar to those produced from the expensive refined sugar of food crops, while saving more than 50 percent in enzyme costs than other SSF strategies.