Castellón César I, Taboada María E
Departamento de Ingeniería Química y Procesos de Minerales, Facultad de Ingeniería, Universidad de Antofagasta, Av. Angamos 601, Antofagasta 1240000, Chile.
Materials (Basel). 2023 Mar 13;16(6):2312. doi: 10.3390/ma16062312.
One of the main problems in processing chalcopyrite ore with hydrometallurgical methods is its refractoriness, which is due to the formation of a layer that inhibits the contact of the ore with the leaching solution, thus reducing the dissolution rate. The main objective of this paper is to evaluate the leaching potential of iodide ions in copper extraction from chalcopyrite concentrate in an acidic seawater medium. Leaching tests were carried out in glass reactors stirred at 45 °C. Parameters such as iodide salt concentration and acidity were evaluated in ranges of 0-5000 ppm and 0-1.0 M, respectively. According to the results obtained, adding iodide ions to a medium acid enhances the leaching kinetics in the chalcopyrite concentrate, observing that it improves copper extraction at low concentrations of 100 ppm KI compared to high concentrations of 5000 ppm KI. As a result, part of the iodide required to oxidize copper tends to sublimate or is associated with other ions producing iodinated compounds such as CuI. Copper extraction reached 45% within the first 96 h, while at 216 h, it reached an extraction of close to 70% copper. The recovery rate improves at potentials between 600 and 650 mV, while at lower potentials, the copper extraction decreases. The mineral surface was analyzed using SEM/EDS and XRD analyses for the identification of precipitates on the surface, finding porous elemental sulfur and precipitated jarosite. An increase in iodide ions improves the leaching kinetics in the chalcopyrite concentrate, observing that it improves copper extraction at low concentrations of 100 ppm KI compared to high concentrations of 5000 ppm KI. As a result, part of the iodide required to oxidize copper tends to sublimate or is associated with other ions producing iodinated compounds such as CuI. Copper extraction reached 45% within the first 96 h, while at 216 h, it reached an extraction of close to 70% copper. The recovery rate improves at potentials between 600 and 650 mV, while at lower potentials, the copper extraction decreases. The mineral surface was analyzed using SEM/EDS and XRD analyses for the identification of precipitates on the surface, finding porous elemental sulfur and precipitated jarosite.
采用湿法冶金方法处理黄铜矿矿石的主要问题之一是其难熔性，这是由于形成了一层抑制矿石与浸出溶液接触的物质，从而降低了溶解速率。本文的主要目的是评估在酸性海水介质中，碘离子从黄铜矿精矿中提取铜的浸出潜力。浸出试验在45℃搅拌的玻璃反应器中进行。碘盐浓度和酸度等参数分别在0 - 5000 ppm和0 - 1.0 M范围内进行评估。根据所得结果，向中等酸性介质中添加碘离子可提高黄铜矿精矿的浸出动力学，观察到与5000 ppm KI的高浓度相比，在100 ppm KI的低浓度下能提高铜的提取率。结果，氧化铜所需的部分碘化物倾向于升华或与其他离子结合生成碘化化合物，如CuI。在最初的96小时内铜提取率达到45%，而在216小时时，铜提取率接近70%。在600至650 mV的电位下回收率提高，而在较低电位下，铜提取率降低。使用扫描电子显微镜/能谱仪（SEM/EDS）和X射线衍射（XRD）分析对矿物表面进行分析，以识别表面沉淀物质，发现了多孔元素硫和沉淀的黄钾铁矾。向中等酸性介质中添加碘离子可提高黄铜矿精矿的浸出动力学，观察到与5000 ppm KI的高浓度相比，在100 ppm KI的低浓度下能提高铜的提取率。结果，氧化铜所需的部分碘化物倾向于升华或与其他离子结合生成碘化化合物，如CuI。在最初的96小时内铜提取率达到45%，而在216小时时，铜提取率接近70%。在600至650 mV的电位下回收率提高，而在较低电位下，铜提取率降低。使用扫描电子显微镜/能谱仪（SEM/EDS）和X射线衍射（XRD）分析对矿物表面进行分析，以识别表面沉淀物质，发现了多孔元素硫和沉淀的黄钾铁矾。
