Deepti Tanjore, Center for Environmental Research and Technology, University of California - Riverside, 1084, Columbia Avenue, Riverside, CA 92507, Jiacheng Shen, Center for Environmental Research and Technology, Bourns College of Engineering, University of California, Riverside, 1084 columbia ave., Riverside, CA 92507, Jian Shi, Center for Environmental Research and Technology Department of Chemical and Environmental Engineering Bourns College of Engineer, University of California at Riverside, 1084 Columbia Avenue, Riverside, CA 92507, and Charles E. Wyman, University of California, Center for Environmental Research and Technology, 1084 Columbia Avenue, Riverside, CA 92507.
Hot water pretreatment is an efficient and industrially scalable process that can break the lignin matrix of cellulosic biomass. High severity treatments facilitate deconstruction of crystalline cellulosic structure but also lead to the dehydration of hemicellulose sugars to furfural and other degradation products. Typically, moderate severity conditions are applied to ensure high recovery of xylose and dissolved xylooligomers. However, xylan along with furfural can be catalytically converted to alkanes that can be used to synthesize jet and other hydrocarbon fuels. Thus, higher severity pretreatment conditions than typically considered for fermentation pathways can improve yields of dissolved carbon (xylan, furfural, glucn, levulinic acid, formic acid, and HMF) and prove to be a more economical for catalytic routes to making biofuels. In the present study, an orthogonal experiment was designed to study hot water treatment of maple wood at 200°C, 220°C, and 240°C for 15, 30 and 45 minutes with sulfuric acid concentrations of 100, 25, 50 (g/l) respectively. At 200°C, the highest total dissolved carbon yield of 9.36 wt% was realized for a reaction time for 15 minutes, while higher reactions times of 30 and 45 minutes lowered the total yields to 6.37 and 4.07 wt%, respectively. The results of treatments at higher temperatures and the effects on enzymatic hydrolysis and other downstream processes will be elucidated in this study, and dilute acid and hot water treatments will be compared for various lignocellulosic biomass materials.
