湿法炼铜的目标是以最低的能源消耗和最高的电流效率生产高品质的阴极铜,如何达成这一目标便成为研究的重点。阳极材料是阳极过电位、电流效率、阴极铜品质的重要影响因素,节能阳极的开发对铜电积工业具有重要的现实意义,其中在铅合金阳极中引入Ag、Ca、Co、RE等合金元素可提升铅合金的机械强度,抑制铅的溶解,提升电催化活性和耐腐蚀性能;在导电基底上制备具有优良导电性和催化活性的β-PbO2、IrO2-Ta2O5、TiB2/β-PbO2、Co3O4等活性层的复合阳极,可提升阳极的耐腐蚀性能,降低析氧过电位;石墨、具有三维结构的铅以及复合PANI/Co3O4可以提高阳极的活性比表面积,提升电流效率;调整电解液中铜酸比例为0.25～0.30、添加古尔胶、硫脲、Co2+也可以提升阳极性能和改善阴极铜品质;此外通过优化电解液温度、极板间距等工艺条件也会影响阳极的寿命和催化活性。主要从析氧阳极的开发、溶液体系调整以及工艺参数优化等3个方面对湿法炼铜节能措施进行介绍,最后,对铜电积节能的发展方向进行了展望。
The aim of copper hydrometallurgy is to produce high-quality cathode copper with the lowest energy consumption and the highest current efficiency. How to achieve this objective has become the focus of research. The anode material significantly influences the anode overpotential, current efficiency and cathode copper quality. Therefore, developing energy-saving anodes holds great practical significance for the copper electrowinning industry. The introduction of alloying element such as Ag, Ca, Co and Re into the lead alloy anode can enhance the mechanical strength of lead alloy, inhibit lead dissolution, and improve its electrocatalytic activity and corrosion resistance; the fabrication of composite anodes with active layers such as β-PbO2, IrO2-Ta2O5, TiB2/β-PbO2 and Co3O4 on conductive substrates, which possess excellent conductivity and catalytic activity, can enhance the anode’s corrosion resistance and reduce the oxygen evolution overpotential; it is found that graphite, lead with a three-dimensional structure and the PANI/Co3O4 composite can enhance both the active specific surface area and current efficiency of anode. By adjusting the copper acid ratio in the electrolyte from 0.25 to 0.30, and adding guar gum, thiourea and Co2+, the performance of the anode can be enhanced and the quality of the cathode copper can be improved. Furthermore, optimizing process conditions such as the temperature of the electrolyte and electrode spacing can also impact the anode’s lifespan and catalytic activity. In this paper, energy-saving measures for hydrometallurgical copper refining were mainly introduced from three aspects: the development of oxygen-evolving anodes, adjustments to the solution system, and optimization of process parameters. Finally, the future development direction of energy-saving in copper electrowinning was discussed.
