METHOD FOR EXTRACTING METALS FROM METAL-CONTAINING MATERIALS BY PYROHYDROLYSIS

摘要

The invention relates to a method for extracting metals from metal-containing materials, especially waste, by pyrohydrolysis, the metal-containing materials which contain at least one or more of the metals from the group consisting of Zn, Cd, Pb, Hg, Cu, Sn (as Sn(0) and Sn(II)), As, Sb, Au, Ag and Bi, being made to react at 700-1100 DEG C, advantageously 800-900 DEG C, with a gas composition which at least comprises 25-45 % by volume of water vapour, 0-12 % by volume of carbon dioxide, 2-20 % by volume of hydrogen chloride, 0-15 % by volume of carbon monoxide, the remainder being nitrogen and possibly oxygen, the metals from the abovementioned group being extracted in the form of volatile metal chlorides. More in particular, metal-containing materials are used which also contain one or more metals from the group consisting of Fe, Cr, Mn, Ni, Mg, Ca, Al, Si, Ti, Co and Zr, said last group of materials being hydrolysed, under the reaction conditions, to give non-volatile metal oxides, or remaining, in the oxidic form or form (2) a non-volatile metal chloride and therefore remaining behind in the starting material.