(404b) A Kinetic and Mass Transfer Model for Glycerol Hydrogenation in A Trickle Bed Reactor

Glycerol hydrogenation to propylene glycol was carried out in trickle bed reactor over a broad range of reaction conditions. Outlet glycerol conversion, selectivity to PG, and temperature profiles along the trickle bed were collected experimentally to characterize the system. A detailed model of glycerol hydrogenolysis has been developed that includes a mechanistically based kinetic rate expression, energy transport, mass transport through the liquid phase, and partial wetting of the trickle bed. Optimal kinetic parameters based on all collected data from the trickle bed system were determined via regression analysis. Model predictions agree with experimental data and accurately predict trends in reactor performance with liquid flow rate, temperature, hydrogen pressure, and base promoter concentration. The kinetic rate expression represents truly intrinsic kinetics and is compared with batch reactor data to unify reactions in both environments. The model is thus a useful tool for predicting laboratory reactor performance and for preliminary design of commercial-scale trickle bed systems.