The raffinate in the extraction process contains plenty of acid and metallic ions, the dispose of which causes the resource loss and environmental pollution. The present study proposed an innovative way to solve this problem by using raffinate as the leaching agent in the copper leaching process. The effects of significant leaching parameters were investigated and optimized using the central composite design (CCD) of response surface methodology (RSM). A maximum leaching efficiency of 96.74 % can be obtained under the 53.22 Kg/t of initial acidity, 2.54 h of leaching time and 5.95 of liquid/solid ratio. In addition, the comparative features of samples before and after leaching process were analyzed by using the X-ray diffraction (XRD), sieving test, scanning electron microscope (SEM) and adsorption-desorption isotherms. We found that the majority of copper components have been removed from copper ores, causing the reduction of size distributions. Specifically, the content of <38 μm after leaching was largely increased from 43.71% to 85.00%. It also led to the appearance of micro pores and cracks in the copper ores, so as to increase the specific surface area and the adsorption mean aperture, which were beneficial to the copper leaching process.

提取过程中的提余液含有大量的酸和金属离子，这些离子的处理会造成资源损失和环境污染。本研究提出了一种新颖的方法，通过在铜浸出过程中使用萃余液作为浸出剂来解决该问题。使用响应面方法（RSM）的中央复合设计（CCD）对重要浸出参数的影响进行了研究和优化。在初始酸度为53.22 Kg / t，浸出时间为2.54 h，液/固比为5.95的条件下，最大浸出效率为96.74％。此外，通过X射线衍射（XRD），筛分试验，扫描电子显微镜（SEM）和吸附-解吸等温线分析了样品浸出前后的比较特征。我们发现大多数铜成分已从铜矿石中去除，从而导致尺寸分布减小。具体而言，浸出后<38μm的含量从43.71％大幅增加至85.00％。这也导致铜矿中出现微孔和裂纹，从而增加了比表面积和吸附平均孔径，有利于铜的浸出过程。