Phenol oxidation in a periodically operated trickle bed reactor

The present contribution reports an experimental study of the oxidation of phenol aqueous solutions over a CuO/γ-Al2O3 catalyst carried out in a trickle bed reactor. Steady-state as well as periodic on-off experiments were performed. In the range of operating conditions studied, it was observed that liquid flow modulation has a mild effect on phenol conversion but it does affect product distribution, favoring the mineralization process. When the liquid flow is halted, the intermediate products remain inside the catalyst and are further oxidized to final products. The residence time of the intermediates and the average oxygen concentrations inside the catalytic pellet during liquid flow modulation are higher than those attained in steady-state operation.