Process for producing elemental sulfur from an H.sub.2 S-containing gas

US5262135A · kind A · utility

Assignee

• Metallgesellschaft AG · DE

Inventors

• Rainer Lell · Nidderau, DE
• Klaus Stetzer · Dreieich, DE

Key dates

• Filing date: Mar 26, 1992
• Grant date: Nov 16, 1993
• Expiry date: Mar 26, 2012

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01B17/0465
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

The gas to be treated contains H.sub.2 S and carbon compounds first enters the combustion chamber of a Claus process plant and a gas mixture which contains 1 to 3 moles H.sub.2 S per mole of SO.sub.2 is withdrawn from that combustion chamber. The gas mixture is reacted in part to form elemental sulfur in at least one catalytic Claus process stage at temperatures above the dew-point temperature of the sulfur. The elemental sulfur is condensed in and removed from a sulfur cooler. An exhaust gas which contains 0.5 to 5% by volume H.sub.2 S and also contains COS, CS.sub.2 and H.sub.2 O is withdrawn from the last sulfur cooler of the Claus process plant. Oxygen is admixed with that exhaust gas, which is heated to a temperature of at least 200.degree. C. and is contacted with a catalyst, which comprises at least 80% by weight TiO.sub.2. The resulting elemental sulfur is condensed and withdrawn. The gas is subsequently contacted at temperatures of 120.degree. to 160.degree. C. with a catalyst which comprises at least 80% by weight Al.sub.2 O.sub.3.