Ferric chloride prepn. - from waste ferrous chloride soln. e.g. from etching processes, by chlorination and concn.

摘要

Ferric chloride is prepared in solution by evaporating a soln. of ferrous chloride to concentrate it and simultaneously adding Cl2. The chlorination is effected first, pref.in Venturi effect chlorometers located between sources of Cl2 and FeCl2. The concn. is then carried out in a closed circuit, with external application of heat. FeCl3 can be produced from industrial scrap FeCl2 of low concn. produced during etching of ferrous material with HCl, with saving of cost of normally expensive raw materials.