Pretreatment, saccharification, and fermentation in one-pot reactions using a novel pretreatment catalyst

The typical cellulosic ethanol production process comprises pretreatment, solid/liquid separation, solids washing, liquid neutralization and detoxification, enzyme hydrolysis, and ethanol fermentation. These multiple steps contribute to the high cost cellulosic ethanol production. In this study, we propose a one-pot reaction concept for ethanol production using lignocellulose, in which several essential parts of the conventional cellulosic ethanol process are eliminated. Specifically, the steps such as the solid/liquid separation after biomass pretreatment, the separation of sugars and inhibitors, and the detoxification or conditioning for the removal or conversion of enzyme or fermentation inhibitors were skipped, and the entire biomass was processed to ethanol in one pot with only pH adjustment for fermentation. This one-pot reaction process was enabled by the novel acid-base mixture catalyst that showed performance similar to dilute acid but caused much less amount of inhibitors than dilute acid. This innovative process will lead to a substantial reduction in the production cost of cellulosic ethanol.