ABSTRACT

Recycling of waste printed circuit boards (PCBs) receives increasing attention due to abundant metallic resources and significant environmental threats. This work proposes a process for copper recovery from PCBs by froth flotation and oxidation leaching. Copper grade is improved from 38.70 % to 68.34 % with the recovery of 88.76 % by froth flotation, and froth flotation is significantly influenced by copper liberation and particles dispersion of PCB powders. Process variables of oxidation leaching are examined by response surface methodology (RSM). A reliable mathematical model is obtained to predict the response as a function of independent variables and their interactions. Oxidation leaching is remarkably influenced by experimental variables, and the interactions between sulphuric acid and hydrogen peroxide are significant. Optimum conditions are achieved as sulfuric acid 1.0 mol/L, hydrogen peroxide 17 %, temperature 50 °C and time 234 minutes, and the maximum leaching ratio of Cu is up to 99.94 %, indicating that oxidation leaching is an effective method for Cu recovery from PCBs.

摘要

由于丰富的金属资源和重大的环境威胁，废印刷电路板（PCB）的回收越来越受到关注。这项工作提出了一种通过泡沫浮选和氧化浸出从PCB中回收铜的方法。通过泡沫浮选将铜品位从38.70％提高到68.34％，回收率达到88.76％，并且泡沫浮选受铜的释放和PCB粉的颗粒分散性的显着影响。氧化浸出的工艺变量通过响应面法（RSM）进行检查。获得了可靠的数学模型，以根据独立变量及其相互作用来预测响应。氧化浸出受到实验变量的显着影响，硫酸和过氧化氢之间的相互作用非常重要。