GB352477A - Process of recovering sulphur from sulphide minerals - Google Patents

Abstract

Sulphur is recovered from the gases evolved during the smelting of sulphide ores, such as copper pyrites, with a solid reducing agent, e.g. coke in an enclosed blast furnace by passing the gases, which, by adjustment of the blast, contain no free oxygen, at a temperature of 350-400 DEG C. over a catalyst consisting of a metallic oxide, such as an iron or aluminium oxide, produced from the hydrate and retaining some of the combined water; alternatively, bauxite may be employed. The temperature of the gases should exceed 350 DEG C. and dust is removed prior to the catalytic action by passing them first through a settling chamber and then through an electric precipitator. The contained carbon bisulphide, oxysulphide and sulphuretted hydrogen are acted on by the sulphur dioxide formed to produce elementary sulphur. The reactions are exothermic and the catalytic chamber should be maintained at 350-400 DEG C. and the temperature of the outgoing gases should not exceed 400 DEG C. The reduction of the excess of the sulphur dioxide is effected by the introduction of carbon monoxide, preferably as producer gas, the gases passing through a second catalytic chamber to a condenser, preferably a water-tube boiler, where they are cooled to 150-120 DEG C. Liquid sulphur is withdrawn and the gases pass through an electric precipitating chamber maintained at 125-130 DEG C. where the remainder of the elementary sulphur is deposited. Traces of sulphur and sulphur compounds may be removed by heating the gases and burning them with air in the presence of a catalyst, the sulphur dioxide formed being removed by scrubbing with water.