Catalyst and method for the selective oxidation of sulfur compounds to elemental sulfur

Abstract

The invention provides a catalyst; a method for making the catalyst and a method for using the catalyst to promote the selective oxidation of hydrogen sulfide into elemental sulfur. The catalyst may be prepared by contacting a catalyst support, such as silica, with a solution containing ammonium metal salts, such as ammonium iron citrate and ammonium zinc citrate, and an amount of chloride (e.g., ammonium chloride) that is between about 0.1 and about 20 weight percent of the metal ions in the solution, to produce a support material impregnated with ammonium metal citrate salts and ammonium chloride. This impregnated catalyst support is then dried and calcined to produce a catalyst, such as iron and zinc oxide mixture supported on silica. It has been found that by adding chloride to the impregnated catalyst support prior to calcination and drying, that the sintering of the metal oxides can be controlled and the formation of a mixed metal oxide is promoted. It has also been found that the catalyst of the invention exhibits improved selectivity characteristics when compared to a catalyst prepared without the chloride.

Dependencies are inferred from the claim text.