Kinetic Modeling of Bio-Oil Conversion By Electrocatalytic Hydrogenation and Deoxygenation

Using renewable electricity, electrocatalytic hydrogenation can be used to stabilize biomass-derived pyrolysis oil. Stabilization occurs by electrochemically reducing highly reactive functional groups in bio-oil, such as aldehydes, ketones and aromatics, to more stable alcohols and cycloalkanes. This study develops a comprehensive kinetic model for the electrocatalytic hydrogenation of representative bio-oil compounds. The system under investigation is a two-compartment divided cell with a ruthenium impregnated activated carbon cloth cathode and a platinum anode using a Nafion membrane to separate the electrode compartments. The model, programmed in Matlab, includes mechanisms for all transient phenomena occurring in the electrolytic cell, such as bulk diffusion, intra-particle diffusion, adsorption, charge transfer reactions and surface reactions. The objective is to use this model to find rate constants and other model parameters, determine the rate-limiting steps, and identify the most sensitive variables to better understand the process and improve its performance. The development of this kinetic model is a crucial step towards scale-up of electrocatalytic hydrogenation as a keystone of novel pyrolysis-based bioenergy systems.