Process for the manufacture of an anhydrous melt containing stannous chloride and containing only small quantities of oxide and oxychloride

摘要

112.8 kgs. of hydrated stannous chloride, in commercial form or made by dissolving fine tin in hydrochloric acid, is heated in a cast iron or graphite crucible until it dissolves in its own water of crystallization. 37.3 kgs. of potassium chloride, e.g. as sylvine, is added and the mixture heated and stirred until it dries and then again becomes molten, at 224 DEG C. The KCl, Sn CI2 formed may be cast or used immediately for tinning metals.ALSO:Iron, copper and alloys of iron, copper or zinc are tinned by immersion in a salt bath formed by melting potassium and stannous chlorides in proportions such that more than 38 per cent KCl is present and preferably in proportions corresponding to KClSnCl2. Other fusible salts, such as halides of alkali metals, alkaline earth metals and zinc may be present. Reference is also made to fused mixtures of stannous chloride with sodium, ammonium, magnesium, calcium, barium and zinc chlorides.