Process for removing sulfur compounds from a gas with hydrogenation and direct oxidation steps

摘要

A process for removing sulfur from a gas containing sulfur compounds as H2S, SO2, COS, CS2 . . . , in a quantity of up to 15% wt; particularly gases emanating from the Claus process: A first hydrogenation of the sulfur compounds into H2S, the hydrogenation gas being used to regenerate a deactivated bed of oxidation catalyst, both being carried out at 200-500° C. After sulfur removal, the resulting gas undergoes a second hydrogenation step and then a direct oxidation step, said step being operated under the dew point of sulfur to trap the formed sulfur in the catalyst. In the further cycle, the gas streams are switched so as to regenerate the catalyst in run which is deactivated.

主权项

1. A process for removal of sulfur compounds contained in a gas to be processed containing up to 15% volume of sulfur compounds expressed as H2S, said process comprising:
1) first hydrogenating of said sulfur compounds into H2S, in the presence of hydrogen over an hydrogenation catalyst, the gas entering at a temperature of 200-320° C., 2) directly oxidating of H2S into elemental sulfur in the presence of oxygen over a bed of direct oxidation catalyst, at a controlled temperature below sulfur dew point, depositing elemental sulfur in the catalyst bed and obtaining a purified gas, 3) regenerating of deactivated direct oxidation catalyst, regeneration being carried out in-situ by passage of a hot gas at a temperature above the sulfur dew point, then cooling gas obtained, condensing and separating of elemental sulfur, obtaining an elemental sulfur depleted gas and a regenerated catalyst, wherein
regeneration is carried out by the passage of the hot gas issued from the first hydrogenation step, elemental sulfur depleted gas undergoes a second hydrogenation in the presence of hydrogen over an hydrogenation catalyst, the gas entering at a temperature of 122 to 320° C., and direct oxidation of the obtained gas.