Commercializing Cellulosic Ethanol- Highlights

This post highlights some of NREL’s recent advances in cellulosic ethanol production.

NREL researches on two aspects of Cellulosic ethanol production:

a. Biochemical: NREL investigates pretreatment, hydrolysis, and fermentation steps as well as process integration and biomass analysis.

b. Thermo chemical processes: NREL researches catalyst development, process development, and process.

NREL, like other cellulosic ethanol companies like Mascoma, Iogen etc... is investigating on a cheaper pretreatment methods for commercializing cellulosic ethanol. One of the breakthroughs in NREL was when their research team deciphered that the lignin produced as a by-product can be redeposited into cellulose under certain pretreatment conditions which would create a barrier to effective cellulose hydrolysis thereby reducing the sugar yield. Efforts are underway to understand the lignin redeposit so as to prevent the detrimental effects.

NREL pretreatment processes use enzymes for providing a milder pretreatment, as it drastically reduces the pretreatment costs and most importantly, controls the sugar degradation losses. However, there is a problem here; it is extremely hard to maintain a high level of effectiveness with this mild pretreatment process. NREL has therefore used Hence, enzymes are used to further breakdown the hemicelluloses after the pretreatment process. . Breaking down the hemicelluloses also enhanced cellulose hydrolysis, resulting in a 6% higher glucose yield.

NREL is evaluating many different process options and their associated costs to help identify key barriers to low-cost ethanol production. NREL models also highlight the need for extensive heat integration and quantify performance targets needed to achieve DOE’s ethanol cost goals thermo chemically


For those interested to read the whole of NREL recent advances – Full article