Mineralogical Phase Transform of Salt-roasted Concentrate and Enhancement of Gold Leaching by Chlorine-hypochlorite Solution

소금-소성정광에 대한 광물학적 상변화와 염소-차아염소산 용액을 이용한 금 용출 향상

  • Received : 2012.11.13
  • Accepted : 2013.03.21
  • Published : 2013.03.31


In order to optimize the gold leaching process from refractory sulfide concentrate, a chlorine-hypochlorite solution with varying concentrations and temperatures were applied to salt-roasted concentrate. The concentrate consisted of pyrite, chalcopyrite, and galena, which were turned into hematite through air-roasting at $750^{\circ}C$. Also these concentrates were changed into hematite and nantokite (CuCl)) through salt (NaCl)-roasting at $750^{\circ}C$. The results of the gold leaching experiments showed that the best gold leaching parameters were obtained when the hydrochloric acid-sodium hypochlorite mix was at a ratio of 1 : 2, the added concentration was 1.0 M concentration, the pulp density was 1.0%, and the leaching was done at a $60^{\circ}C$ leaching temperature. The leaching rate for gold was much greater in the roasted concentrate than in the raw concentrate. The leaching rate was greater in the salt-roasted concentrate than in the plain roasted concentrate too. From XRD analysis, quartz was found in the salt-roasted concentrate and in the solid residue from the chlorine-hypochlorite leaching solution at $60^{\circ}C$.


refractory sulfide concentrate;phase transformation;salt-roasted concentrate;gold leaching;chlorine-hypochlorite solution


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