LEAD PRODUCTION METHOD Russian patent published in 2015 - IPC C22B13/00 C22B7/00 C22B3/10 

FIELD: metallurgy.

SUBSTANCE: method includes the treatment of lead-bearing raw materials by the solution of chloride of alkaline metal and hydrochloric acid, separation of insoluble precipitate from the solution, crystallisation from the solution of lead chloride, its separation, purification of the obtained master solution from sulphate ion and its return for treatment of lead-bearing raw materials, obtaining of lead and hydrochloric acid which is returned for treatment of lead-bearing raw materials. Meanwhile from lead chloride after its crystallisation by dissolution in water the solution of lead chloride is obtained. The solution is treated by ammonium carbonate with obtaining of lead carbonate which is separated with obtaining of ammonium chloride solution. The lead carbonate is decomposed thermally into lead oxide and carbon dioxide. From lead oxide the lead is obtained, and the ammonium chloride obtained by separation of lead carbonate is treated by calcium hydroxide with obtaining of ammonia and calcium chloride. From calcium chloride and sulphuric acid the hydrochloric acid is obtained. From carbon dioxide, obtained by thermal decomposition of lead carbonate, and from ammonia the ammonium carbonate is obtained which is returned for treatment of chloride lead solution.

EFFECT: avoidance of formation of sulphurous gas and vapours of chlorides and creation of closed production cycle, obtaining of commodity lead without use of electrolysis for regeneration of reactants that improves environmental friendliness of lead production.

4 cl, 2 ex