盐酸溶液中双氧水浸出黄铜矿（英文）

Leaching of chalcopyrite with hydrogen peroxide in hydrochloric acid solution

本文旨在研究以双氧水为强氧化剂的黄铜矿精矿的盐酸浸出过程。研究搅拌速度、固液比、温度、HCl和H_2O_2浓度等浸出参数对金属浸出率的影响。室温下,用3.0 mol/L H_2O_2和0.5 mol/L HCl溶液与黄铜矿反应180 min后,获得33%的最大铜浸出率。结果表明,在反应的前60 min,铜的浸出率增大;此后,由于双氧水的快速催化分解,铜浸出率基本上保持不变。此外,固液比对铜的浸出率影响显著,而且在最稀的悬浮液中(即固液比1:100)铜的浸出率最高。溶出过程可用一级动力学方程描述,表观活化能为19.6 kJ/mol,表明溶出过程受扩散控制,对于HCl和H_2O_2的反应级数分别为0.30和0.53。浸出渣的XRD和SEM/EDS分析结果表明,矿物表面生成单质硫,抑制浸出率的提高。

The aim of this work was to investigate the leaching of chalcopyrite concentrate in hydrochloric acid with hydrogen peroxide as a strong oxidizing agent. The effects of the leaching variables on metal extraction, such as stirring speed, solid-to-liquid ratio, temperature and HCl and H2O2 concentrations, were studied. The maximum final copper extraction of 33% was attained with 3.0 mol/L H2O2 in 0.5 mol/L HCl at room temperature after 180 min of the reaction. The results showed that the copper extraction was increased in the first 60 min of reaction, after which it essentially ceased due to the fast catalytic decomposition of hydrogen peroxide. Further, solid-to-liquid ratio affected the copper extraction significantly and the highest copper extraction was obtained in the most dilute suspension（i.e., S/L ratio of 1：100）. The dissolution process was described by the first order kinetics equation. The apparent activation energy of 19.6 k J/mol suggested that the dissolution process was under diffusion control. The reaction orders for HCl and H2O2 were established to be 0.30 and 0.53, respectively. The results of the XRD and SEM/EDS analysis of the leaching residue indicated the generation of the elemental sulphur on mineral surfaces which tended to inhibit the leaching rate.