Modelling of trickle bed reactor for the catalytic wet air oxidation of phenol

A non-isothermal trickle-bed transport-reaction model has been developed and tested for the catalytic wet air oxidation of phenol over CuO/gamma-Al2O3. Isothermal simulations confirmed that partial catalyst wetting, and the resulting gas-solid mass transfer, leads to higher phenol conversions, when oxygen is the limiting reactant. Non-isothermal simulations evidenced that phenol conversion and adiabatic temperature rise may be overestimated if water evaporation is neglected. When accounting for the latter, the temperature rise exhibited a maximum at gas velocities slightly above the stoichiometric demand for complete mineralisation. It was further observed that under the conditions studied, the temperature rise levels off with increasing inlet phenol concentration, while with increasing inlet temperature it reaches a maximum and then drops.