10-07: Targeted conversion of hemicellulose and cellulose into reactive intermediates by a single phase solvent process

Reactive intermediates (RIs) from cellulosic biomass such as sugars and their dehydration products are important building blocks for the sustainable production of biofuels and biochemicals. However, many current processes are not feedstock agnostic, and the RI yields are insufficient to be commercially viable for biofuel production. Therefore, it is crucial to develop an integrated conversion process that supports a diverse range of raw feedstock types to eliminate the need for additional pretreatments or other steps to realize high yields. Since pentoses in hemicellulose are more easily removed than glucose in cellulose, co-production of dehydration products from both fractions has proved to be challenging. In this study, we propose a targeted conversion strategy that utilizes a single phase solvent process to enhance the production of RIs from cellulosic biomass. In a single step, (1) xylan from hemicelluose was hydrolyzed and dehydrated into furfural at high yields, (2) hexosans were partially hydrolyzed and converted into levulinic acid at high yields, and (3) acid-insoluble lignin was dissolved into the liquid phase. Fermentable glucose was then produced from the remaining material after a filtration step, and the dissolved lignin was isolated after the solvent was recovered by vacuum distillation.

Keywords: Biomass conversion, furfural, levulinic acid, fractionation, hydrolysis, dehydration