Catalysts for Treating H2S Malodor Problem at Ambient Temperature

Malodor can cause discomfort, and long term exposure is known to have serious health consequences. H₂S is one of the major malodor pollutants generated from anaerobic decomposition of sulfur-containing organic matter, and often found in domestic and industrial situations, and particularly in sewer lines. Existing solutions to H₂S problem including Claus process, which uses catalyst to convert H₂S into sulfur at high temperature (about 500 K), and the use of adsorbents. These are energy intensive processes that are not sustainable. This work presents a new route to convert H₂S under room temperature and humid conditions, which suits for the applications near the malodor source such as sewer. Vanadia-titania catalyst (V₂O₅/TiO₂) is successfully developed to treat H₂S at room temperature. The optimized catalyst can treat H₂S concentrations in the range of 3 to 35 ppm that are often found in practical situation. XPS was used to monitor sulfur accumulation on the surface and their potential impact on the catalyst activity. It was found that not only the catalyst is active for H₂S abatement at room temperature, but also tolerant of S deposition. Thus, negligible catalyst deactivation was observed under prolonged reaction.