| 摘要 |
The method for refining of Au and Ag from ore comprises (1) mixing it with a flux (ore:1000, NaOH:200-300, KNO3:30-50, Zn-Cu alloy powder (or PbO):150-250, CaO:300-400, NaHCO3:280-320, Borax:80- 150, C:40-60, flourite:100- 200, silica:100-150, Na2SO4 or NaSO3.7H2O or Na2S:80-150, in wt.%), (2) melting it at 1800- 2000 deg.C and separating by maintaing melts for 90-100 min, (3) after remelting and quenching, thus obtained granular metal is dissolved by nitrohydrochloric acid, precipitating AgCl by air cooling it for 24 hrs, filtering AgCl from soln. which is neutralized by urea or H2O2, then precipitating Au by air cooling of neutralized soln. projected by Na2SO3.7H2O, and purifying Au and Ag p.p.t. by ZnO and H2SO4, (4) roasting a mixture or Au, Ag and fluorite to 5% of each metal at 780-820 deg.C, and (5) refining of Au and Ag with flux (Borax:35, NaHCO3:35-45, silica:15-20, C(purity:99.0-99.7%):5-6, in wt.%, when metal is 100 wt.%) by melting at 1000-1200 deg.C in crucible.
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