Trickle bed reactor technology for propylene epoxidation with extrudates – Catalyst characterization, kinetic studies and modelling

Titanium silicate (TS-1) extrudates were prepared, characterized and tested in a trickle bed reactor (TBR) for selective epoxidation of propylene to propylene oxide. Hydrogen peroxide was used as the epoxidation agent. A preliminary study was conducted with extrudates with a diameters 1.5–3 mm. The smallest extrudate showed the highest propylene conversion and was used for an extensive screening of the reaction conditions (temperature, pressure, liquid and gas flow rates, composition of the educt solution). A dynamic multiphase reactor model was developed based on the steady state reaction kinetics approach. The internal mass transfer effects inside the extrudates were described with a reaction–diffusion model and the backmixing effects inside the catalyst bed were modelled with the axial dispersion concept. The mass balances of the components in the gas, liquid and solid catalyst phases were solved numerically with gProms ModelBuilder. The prediction of the model was for the most experimental data within +/- 10 %. The model was used to the simulate the concentration profiles of the participating molecules in time and space.