GB370965A - Improvements in or relating to processes for eliminating chlorine from solutions containing zinc chloride and to improved solutions obtained thereby - Google Patents

Abstract

A process for eliminating chlorine from solutions, as of zinc sulphate, containing zinc chloride comprises adding copper sulphate, and copper powder to convert the cupric chloride thus formed to insoluble cuprous chloride, which is removed. The quantity of copper sulphate, which may be present at least in part in the solution treated, is preferably adjusted to be twice that theoretically required, and the copper powder, preferably obtained electrolytically at high current density, should be added in large excess, for example, ten times the theoretical quantity. The cuprous chloride may be reconverted to finely divided copper, which may be employed in place of the electrolytic copper, by treatment with zinc balls, scrap, &c. In an application of the process, zinc-containing alloys, as brass, admixed with coal and if required with zinciferous ores, are treated in a blast furnace. The evolved fume is collected, and the residue admixed with a large quantity of alloy and blown. Copper obtained from the converter passes to electrolytic refining operations. The fumes from this and the previous operation, containing zinc, zinc oxide and sulphate, lead oxide, copper oxide, copper, tin, and silver are dissolved in sulphuric acid and treated for the removal of chlorine as above. The solution, containing 0,3 per cent of chlorine or less, after further treatment, may be used for the preparation of lithopone. The Specification as open to inspection under Sect. 91 (3) (a) comprises the removal of chlorine present in solution as chlorides generally. This subject-matter, in its wide aspect, does not appear in the Specification as accepted. Reference has been directed by the Comptroller to Specifications 276,200 and 285,662, [both in Class 1 (iii), Oxides &c., Metallic].ALSO:In an application of a process for removal of chlorine from solutions containing zinc chloride, zinc-containing alloys, as brass, ad-mixed with coal and if desired with zinciferous ores, are treated in a blast furnace. The evolved fume is collected, and the residue admixed with a large quantity of alloy and blown. Copper obtained from the converter passes to electrolytic refining operations. The fumes from this and the previous operation, containing zinc, zinc oxide, and sulphate, lead oxide, copper oxide, copper, tin, and silver are dissolved in sulphuric acid, and treated for the removal of chlorine. Reference has been directed by the Comptroller to Specifications 276,200 and 285,662, [both in Class 82 (i), Metals, Extracting &c.].