Ultrasound assisted photocatalytic degradation of diclofenac in an aqueous environment

Diclofenac (DF) is an anti-inflammatory drug found in aqueous environments as a pollutant due to its widespread use. The sonolytic, photocatalytic and sonophotocatalytic degradation of DF using three photocatalysts (TiO2, ZnO and Fe–ZnO) were studied. The degradation of DF followed first-order like kinetics. The sonophotocatalytic degradation using TiO2 under UV–vis radiation showed a slight synergistic enhancement in the degradation of the parent compound, whereas a detrimental effect was observed for the mineralization process. In the case of Fe–ZnO, both degradation and mineralization showed near additive effects. A number of degradation products were identified.