High-Efficiency Conversion of Ionic Liquid-Pretreated Woody Biomass to Ethanol at the Pilot Scale

With a diverse and widely distributed global resource base, woody biomass is compelling organic feedstock for conversion to renewable liquid fuels. In California, comprises the largest fraction of underutilized available biofuel production, but fuels challenged both by recalcitrance deconstruction toxicity toward downstream saccharification fermentation due acids phenolic compounds generated during pretreatment. this study, we optimize pretreatment scale-up an integrated one-pot process California using ionic (IL) cholinium lysinate [Ch][Lys] as solvent. By evaluating impact solid loading, removal, yeast acclimatization, temperature, pH, nutrient supplementation on final ethanol yields titers, achieve nearly full glucose xylose with commercial C5-utilizing Saccharomyces cerevisiae. We then demonstrate scalability in 680 L pilot-scale fermentation, achieving >80% efficiency, >90% 27.7 g/L titer, distillation efficiency from IL-containing hydrolysate post fermentation. This fully requires no intermediate separations detoxification hydrolysate. Using biorefinery model, current performance results minimum selling price $8.8/gge. Reducing enzyme loading along other minor improvements can reduce $3/gge. study scale demonstration IL known date, overall biomass-to-ethanol efficiencies are highest reported date any IL-based biomass-to-biofuel conversion.