Abstract: This invention provides a catalyst and method for removing sulphur compounds from a fluid stream and decomposing such compounds to produce sulphur. Sour natural gas can be sweetened effectively by this invention, and sulfur can be prepared thereby. The invention employs a catalyst containing an alkali metal sulfide and sulfides(s) or selenide(s) of metal(s) showing polyvalent and/or amphoteric character, e.g. Zn, etc. The catalyst is generally impregnated on a microporous type support (e.g., alumina) and is capable of providing reactive oxygen. Its activity is sustained by exposure to small amounts of oxygen either while decomposing the sulphur compound, or thereafter.