(85a) Evaluation of Ultrasonic Pretreatment on Catalytic Hydrothermal Liquefaction of Woody Biomass

In this study, ultrasonication pretreatment of a woody substrate (e.g., pinewood) was evaluated to understand its effectiveness on different products generated during catalytic hydrothermal liquefaction processing. It was anticipated that the ultrasonication would break open the cell walls by cleaving the chain linkages among the macromolecules and releasing polysaccharides. Ultrasonication of previously pulverized and milled Pinus ponderosa in water was performed using a 20 kHz probe and the effect of different ultrasonic parameters such as power input, time of sonication and slurry composition was evaluated. Ultrasonically pretreated woody biomass was treated with hydrothermal liquefaction in the presence of a Ca-salt catalyst in a bench scale 300 mL SS 316 Parr batch reactor at 250^oC with some initial N₂ pressure for 1-2 hours. Hydrothermally processed slurry was filtered, and heavy bio-oil (HBO) was extracted with acetone. The products such as HBO and char were analyzed by elemental analyzer for CHNO and calorific value was calculated. The aqueous biocrude was also analyzed by GCMS to identify oxygenated hydrocarbons. The results obtained with catalytic hydrothermal processing of ultrasonically pretreated pinewood will be presented.