Date of Graduation
Bachelor of Science in Biological Engineering
Biological and Agricultural Engineering
Organic solvent pretreatment, commonly known as organosolv, is a method used to prepare biomass for enzymatic hydrolysis for the production of biofuels. This method common uses ethanol as the organic solvent. However, this creates an economic issue with the product stream, as ethanol becomes a product and input. This project sought to explore how decreasing the use of ethanol in organosolv pretreatment affected the recoverability of sugars after enzymatic hydrolysis. Loblolly pine (Pinus taeda L.) was pretreated at 170 °C for 60 minutes in 1% dilute sulfuric acid and an ethanol concentration varying from 65% to 35%. Compositional analysis was then performed on each pretreated sample to determine composition of glucan, lignin, xylan, and arabinan. The pretreated samples were then enzymatically hydrolyzed and the concentrations of the resulting sugars were analyzed by high pressure liquid chromatography (HPLC). Results from the compositional analysis showed that although lignin composition decreases with increasing ethanol concentration, there is very little delignification happening during the pretreatment process. Results from the enzymatic hydrolysis indicated that ethanol concentration above 35% results in similar recoveries, approximately 70% of glucan available. Overall, results indicated that lignin was not the only limiting factor during enzymatic hydrolysis. Additionally, the results indicated that sufficient sugar recovery could be achieved at lower ethanol concentrations.
Heringer, Nelson B., "Minimizing Ethanol Concentration in Organosolv Pretreatment for the Saccharification of Loblolly Pine" (2016). Biological and Agricultural Engineering Undergraduate Honors Theses. 41.