从铅冰铜中高效选择性提取铜的工艺研究

采用高温高压纯氧氧化法选择性提取铅冰铜中铜, 研究了硫酸用量、浸出温度、反应时间、液固比、氧气压力、搅拌速度以及分散剂木质素用量对铜浸出率的影响及对浸出液中铁含量的影响。铅冰铜经氧压浸出后进行液固分离, 铅冰铜中的铜进入液相中, 绝大部分铁以赤铁矿的形式与铅、银、金等有价金属一起进入渣相中; 浸出后的硫酸铜溶液经调酸后直接进行旋流电解可得到合格的阴极铜产品, 浸出渣返回铅冶炼系统综合回收铅、银、金等有价元素。高温氧压浸出铅冰铜, 铜浸出率可达93.5%, 阴极铜产品质量达到99.975%, 有效实现了铅冰铜中铜的选择性提取。

Technique for Selective Extraction of Copper from Lead Matte

Experiment on selective extraction of copper from lead matte was performed by means of high-temperature and high-pressure oxidation in O₂ atmosphere, and effects of H₂SO₄ dosage, leaching temperature, reaction time, liquid-solid ratio, oxygen pressure, stirring speed and lignin dosage on the leaching efficiency of copper and iron content in the leachate were discussed. In the experiment, a liquid-solid separation was proceeded after an oxygen pressure leaching, leading to Cu in the lead matte pulled into liquid phase and most of Fe into slag in the form of hematite together with other valuable metals, including Pb, Ag, Au. The copper sulfate solution from leaching process was directly subjected to the cyclone electrolysis after pH adjustment, resulting in the qualified cathode copper, while the leach residue was back to lead smelting system for comprehensive recovery of Pb, Ag and Au. It is shown that oxygen pressure leaching of lead matte at an elevated temperature can lead to the selective extraction of copper from lead matte with copper leaching rate up to 93.5%, and the obtained cathode copper product with purity up to 99.975%.