(1. 安徽工业大学 冶金工程学院,马鞍山 243032;
2. 中南大学 冶金与环境学院,长沙 410083)
摘 要: 以复杂难处理金精矿火法造锍捕金所得铁锍合金的硫酸浸出渣为原料,采用控电位氯化浸出工艺分离酸溶渣中的Cu、As、Sb等主要杂质元素,贵金属Au单向富集得到高品位金泥,Au泥经过硫酸化焙烧脱硫进一步富集贵金属金。结果表明:双电极体系控电位氯化浸出优化条件为[H+]5mol/L、浸出电位380 mV、液固质量比5:1、温度85 ℃和搅拌浸出2 h,所得渣率为28.2%,浸出渣中Cu、As、Sb含量分别降到0.18%、0.095%、0.084%,浸出率分别达到99.6%、99.8%、99.8%,浸出渣主要成分Si和S的含量分别为29.39%和22.72%,Au品位富集到2.609%;浸出渣硫酸化焙烧脱硫的烧成率为66.5%,S含量降至0.87%,脱硫率为96.2%,焙砂的主要物相为SiO2和单质金,Au品位富集到3.937%。复杂金精矿铁锍合金酸溶渣通过控电位氯化浸出除杂—焙烧脱硫可将贵金属金有效富集。
关键字: 铁锍合金;酸浸渣;控电位;氯化浸出;金
(1. School of Metallurgical Engineering, Anhui University of Technology, Ma’anshan 243032, China;
2. School of Metallurgy and Environment, Central South University, Changsha 410083, China)
Abstract:The leaching residue of iron matte from the pyrometallurgical matte making process of refractory gold concentrate was used as the raw material to separate the impurities of Cu, As, and Sb with the controlled potential chloridizing leaching process. The precious metal Au was enriched and high-grade gold mud was obtained, which was sent to sulfation roasting desulfurization for further enrichment of Au. The results show that the double-electrode controlled potential chloridizing leaching conditions are 5 mol/L for H+ concentration, 380 mV for leaching potential, 5:1 for liquid to solid ratio, 85 ℃ for temperature and 2 h for leaching time. The residue rate is 28.2%, and the contents of Cu, As and Sb are decreased to 0.18%, 0.095%, and 0.084% with the leaching rates of 99.6%, 99.7% and 99.8%, respectively. The contents of Si and S in the leaching residue are 29.39% and 22.72%, and the Au content is enriched to 2.609%. The sulfation roasting desulfurization of the leaching residue achieved the firing rate of 66.5%. The S content is declined to 0.87% with the desulfurization rate of 96.2%. The major phases of the calcine are SiO2 and metallic Au, with the Au content being enriched to 3.973%. The precious metal Au is effectively enriched by controlled potential chloridizing leaching and roasting desulfurization of the iron matte leaching residue from refractory gold concentrate.
Key words: iron matte alloy; acid leaching residue; controlled potential; chloridizing leaching; gold