Sulfur-resistance properties of WS2-added Pt/TiO2 catalysts for selective catalytic oxidation

An representative method to reduce CO and NH3 emissions is selective catalytic oxidation (SCO). Pt-based catalysts with relatively high resistance to SO2 compared with other materials are widely used for this purpose. However, the sulfuric acid generated from the oxidation of SO2 in the temperature range of 200–300 °C coats the surface of the catalyst, resulting in its deactivation. In this study, we added WS2 to Pt/TiO2 catalyst to synthesize a catalyst that is not easily poisoned by SO2 and shows improved oxidation performance. We confirmed that the coexistence of WS2 and WO3 formed during calcination conferred the catalysts with resistance to SO2. Loading of the catalysts with 3.6 wt% WS2 improved their Pt dispersion and increased the Pt0/Pttotal ratio owing to the formation of Pt0. Our findings suggest a direct method for the efficient preparation of oxidation catalysts with good applicability to the steelmaking industry.