The visible light-driven photodegradation of dimethyl sulfide on S-doped TiO₂: Characterization, kinetics, and reaction pathways

Sulfur-doped TiO₂ prepared by a sol-gel method to degrade dimethyl sulfide (DMS) under visible light irradiation was investigated. The degradation reactions of DMS were performed under various operation conditions. The results indicate that S-doped TiO₂ photocatalysts are mainly nano-size with an anatase-phase structure. Relative humidity and inlet DMS concentration significantly influence the DMS conversion and mineralization. Langmuir-Hinshelwood kinetic models have been used in the analysis of the experimental data obtained. The main oxidation products of DMS photodegradation are SO₂, CO₂, DMDS, DMSO, DMSO₂, CO, and MSA. Two possible mechanisms have been developed for photodegradation of DMS in a dry and a humid environment.