GB310063A - An improved process for eliminating sulphur compounds from gases - Google Patents

Abstract

310,063. Johnson, J. Y., (I. G. Farbenindustrie Akt.-Ges.). Oct. 20, 1927. Purifying processes; materials and compositions for purifying. - Sulphur compounds are removed from coal gas, water gas, or producer gas, by passing the gas with sufficient oxygen or oxygen-containing gas to form sulphur-oxygen compounds, over solid adsorbents, particularly active charcoal or bodies containing it, at 150-250‹ C., or over compounds of alkaline earth metals, aluminium, or heavy metals with non-metals other than oxygen of the 5th and 6th groups of the periodic system. Ammonia is added if necessary before or after the catalytic treatment to ensure the formation of ammonium salts, or the sulphur-oxygen compounds are washed out with aqueous ammonia. Nitrides, phosphides and sulphides of copper and the iron group of metals are suitable agents, the temperature required being up to 400‹ C. In a modification, the adsorbent charcoal is first charged with sulphur in known manner by limiting the oxygen supply, the sulphur then being oxidized by supplying air or oxygen at 150-250‹ C. The hot gases coming from the catalyst may be cooled only to the degree in which sufficient water vapour for the formation of ammonium salts, particularly sulphite, is present, gaseous ammonia then being added and the salts precipitated as in an electrical separator. In an example producer gas containing 2.7 grams of sulphur per cubic metre is mixed with 2 per cent by volume of air and passed over a granular catalytic alloy, consisting of 67 per cent of iron, 22 per cent of phosphorus and 11 per cent of silicon, heated to 400‹ C., 0.4 per cent by volume of gaseous ammonia is mixed with the escaping gases at 350‹ C., the ammonium salts being separated as by means of a high tension electric field. Specification 280,947 is referred to.