REDUCTION OF SULFUR-DIOXIDE OVER ALUMINA-SUPPORTED MOLYBDENUM SULFIDE CATALYSTS

An experimental investigation of the reduction of SO2 with CH4 using molybdenum sulfide supported on alumina as a catalyst was carried out. Three molybdenum loadings of 5, 10, and 15% were used. In addition, a catalyst which contained cobalt (5% Co-15% Mo/Al2O3) was evaluated. The evaluations were based on the activity as well as the yields of sulfur and carbon dioxide. Experiments were carried out at temperatures ranging from 650 to 725-degrees-C and inlet molar feed ratios of SO2 to CH4 of 1.0 and 2.0. The 5 and 10% molybdenum loadings showed similar activities and yields to each other. The catalyst containing 15% molybdenum had the highest activity and yields (above 77% for both sulfur and CO2). All catalysts tested were more effective than alumina itself. The activity of the 15% Mo/Al2O3 catalyst was 1.5-2 times that of alumina. This catalyst was stable under all reaction conditions. The addition of cobalt reduced the activity by 20%. In order to minimize the production of undesired by-products, the reaction temperature should be less than 700-degrees-C.