(648b) Integrated Bio-Refineries of Biocrude Oil Converted from Wet Bio-Waste Via Hydrothermal Liquefaction into Drop-in Fuel and Value-Added Chemical
Biorefineries of biocrude oil products converted from wet biowastes such as swine manure and algae via hydrothermal liquefaction (HTL) are in need of a comprehensive understanding. The goal of this study is to develop multi-phase bio-refineries to expedite the downstream application of biocrude oil into drop-in transportation fuels and value added chemicals, such as nitrogen-doped hydrocarbon electric materials. Our previous study showed that biocrude converted from wet biowaste, such as swine manure, food waste, and mixed-culture algae from wastewater via HTL, contain appreciable higher heating values (HHV) ranging 32-38 MJ/kg, while the HHV of ethanol and gasoline are respectively about 29 MJ/kg and 45 MJ/kg. However, the relatively high concentration of impurities in the biocrude oil, mainly nitrogen (3-7%), oxygen (about 10%) and moisture content (up to 20%), remain problematic that needs to be addressed in order to utilize this source as transportation fuels. Moreover, these impurities will result in NOx emission and corrosion to the engine when used as transportation fuels. As a consequence, further upgrading or separation of the biocrude oil products is critically needed. Several previous studies have demonstrated that catalysts (e.g. zeolites, Pt/C, Raney-Ni, Rh etc.) have little impact on upgrading the biocrude oil when the reaction temperature was below 500 °C. On the contrary, it was reported that after proper separation, such as distillation, the oxygen content in the biocrude oil could be reduced to 5% and the heating values could be increased up to 41-45 MJ/kg, which indicates that there is a high potential to utilize these biocrude oil products as drop-in fuels. This study aims to utilize a pilot scale plug-flow reactor to produce 8-10 gallons of biocrude oil and separate biocrude oil products into drop-in transportation fuels and value-added chemicals with distillation. Preliminary study shows that about 60% of the biocurde product can be distilled out before 250 °C. Distillation curve is also recorded and will be compared to that of jet fuel, diesel and lubricant oil. Elemental and GC-MS analyses demonstrates that the distillate fractions collected between 200-250 °C have similar chemical properties to diesel. Heating values and densities of distillate products were also measured. The non-distillable products were also examined in terms of elemental compositions and SEM microscopy. Physiochemical characterization suggests that the non-distillable products may serve as carbon-based adsorbents or nitrogen-doped electrical capacitors.