(516a) Experimental Kinetics of the Catalytic Hydrotreatment of Model Compounds for Wood-Based Pyrolysis Oil

Pyrolysis oils made from woody biomass are a complex mixture of oxygenated hydrocarbons. Catalytic hydrotreatment can be used to reduce their oxygen content and increase their viability as a “drop-in” transportation fuel, since they can be readily blended with existing fossil fuels as “green gasoline”. However, product distribution depends strongly on the original feedstock composition and reactor processing parameters, especially temperature, hydrogen/oil flow rates and catalyst. We have explored the associated hydrotreatment reaction pathways via experimental kinetic studies on individual paradigm compounds, such as anisole and m-cresol, in a micro-reactor.  The compounds were reacted under an excess of hydrogen using three different types of catalysts: acidic (ZSM-5), hydrogenation (Pd/C) and bi-functional (Pt/Al₂O₃); the reaction kinetics of each compound were studied as a function of temperature and catalyst used. This experimental data has been used to determine rate constants for a hybrid, lumped-parameter kinetic model. This approach groups reaction pathways together into small “lumps” of reaction types, rather than considering each component of pyrolysis oil and each reaction pathway separately. These lumped rate constants are then used to construct a hydrotreatment reactor model of paradigm compounds and wood-based pyrolysis oil, and this model is used to scale-up this process to simulate larger, pilot-scale reactors.