某难浸金矿的次氯酸盐法直接浸金试验研究

采用次氯酸钠溶液法对国内某难浸金矿进行了直接浸出试验研究，考察了NaClO浓度、NaCl浓度和反应时间等条件对浸金率的影响，并采用X射线衍射、XRF、SEM和EDS能谱等测试对金精矿与浸出渣进行了表征，简要分析了浸出机理。试验结果表明：精矿中的金在pH＜8、电位>900 mV的条件下，能够被浸出并形成稳定配合物存在于溶液中，最佳实验条件为NaCl]=50 g/L，NaClO]=200 g/L，液固比=20∶1， 3 h后反应基本完成，金浸出率可达96.26%，脱硫率达98%以上。与传统氰化法相比，次氯酸盐法具有流程短、污染小和反应速度快等优点。

Experimental Study on the Leaching of Gold from a Refractory Gold Concentrate by Chloride-hypochlorite Solution

In this research，sodium hypochlorite solution was used for leaching gold from a refractory gold concentrate.The influence of NaCl and NaClO concentration，and reaction time to the leaching rate were investigated in this experiment.The raw materials and the leaching residue were characterized by a series of analysis methods such as XRD，XRF，SEM and EDS，and the reaction mechanism are analyzed in this paper.Results indicate that the leaching rate and the desulfurization rate can be achieved 96.26% and 98% respectively at most optimum conditions as follows：NaCl concentration 50 g/L，NaClO concentration 200 g/L，liquid-solid ratio 10∶1，the best reaction time was 150 mins，and these conditions should be guaranteed pH<8.0，Eh>900 mV.Experimental results show that the method of chloride-hypochlorite leaching has the advantages of short process，low pollution and higher in reaction rate compared with the traditional cyanidation method.