Kinetic modelling for the photocatalytic degradation of phenol by using TiO 2 ‐coated glass raschig rings under simulated solar light

BACKGROUND Immobilisation of TiO 2 photocatalysts has proven to be an efficient technological approach concerning both practical and economical aspects. The efficiency of photocatalytic phenol degradation using glass raschig rings coated with TiO 2 Aeroxide ® P25 was evaluated in a recirculation reactor operating under simulated solar light irradiation, by comparing the first order reaction rate ( r ) as a function of several operation conditions. RESULTS The reaction rate increases with the initial phenol concentration ([ PhOH ] 0 ), the irradiation intensity ( I ), the number of TiO 2 ‐coated rings ( N ), and the hydrogen peroxide concentration [ H 2 O 2 ], and is minimally affected by the solution's flow rate ( Q ). A kinetic model was developed for the determination of the r as a function of the operating parameters. CONCLUSIONS The empirical model allows the prediction of the efficiency of the photocatalytic degradation process in a wide range of operation conditions, which can be considered a useful tool for the scaling‐up of the water treatment process. © 2014 Society of Chemical Industry