ABSTRACT CTS-9626893 This is a study of molecular structure-activity relationships in the oxidation of sulfur dioxide to sulfur trioxide over supported solid metal-oxide catalysts. (The sulfuric acid contact process, which uses a supported molten salt as the catalyst, is not the subject of this study.) Fundamental issues addressed include the kinetics, the reaction mechanism, the nature of the active site including size and structure, and the effects of the support, surface additives and various gases such as water, nitric oxide, hydrocarbons, and ammonia. Model supported catalysts containing reducible oxides of vanadium, molybdenum, chromium, rhenium, or manganese are synthesized, characterized by Raman, infrared, and nuclear magnetic resonance spectroscopies, and tested for catalytic activity for the subject reaction. This information is used to establish structure-activity relationships for oxidation of sulfur dioxide. The solid-oxide catalyzed oxidation of sulfur dioxide is important in the industrial production of sulfuric acid as well as in several environmental technologies including the DESONOX and SNOX processes for removing nitrogen and sulfur from industrial (including electric power generator) plants and selective catalytic reduction to remove nitrogen oxides, for in which sulfur trioxide is a poison.
