Faculty of Mining, Petroleum and Geophysics, Shahrood University of Technology, Shahrood, Iran.
Environ Sci Pollut Res Int. 2020 Feb;27(6):6239-6252. doi: 10.1007/s11356-019-07199-z. Epub 2019 Dec 21.
This research was aimed to investigate the leaching behavior of zinc and copper from a porcelain stone tailings sample using RSM-CCD modeling. The synergetic and individual effects of five main factors including liquid/solid ratio, sulfuric acid concentration, agitation speed, leaching time, and temperature were examined on the recoveries of zinc and copper. For this purpose, two 2F1 models with R values of 0.9341 and 0.8693 were developed for the relationship between the leaching efficiencies of copper and zinc and effective terms, respectively. The results indicated that the leaching process was significantly influenced by the interactive effects between factors. The leaching recoveries increased by increasing all factors in the range studied. However, the recoveries were nearly independent of the agitation rate, indicating surface chemical reaction as the leaching kinetics controlling step. It was also found that the linear effect of temperature, the interaction effect of leaching time with liquid/solid ratio, and the interactive effect between sulfuric acid concentration and agitation rate had the greatest impact on the leaching rate of copper. Additionally, the linear effect of temperature and the interactive effect of temperature with agitation speed and liquid/solid ratio were distinguished to be the most effective factors on the recoveries of zinc. Moreover, the optimization was performed using desirability function approach, and the highest recoveries of copper (73.95%) and zinc (81.02%) were obtained at an acid concentration of 10%, 300 rpm agitation rate, 10 mL/g liquid/solid ratio, 35 °C temperature, and 75 min leaching time.
本研究旨在采用 RSM-CCD 模型研究从瓷石尾矿中浸出锌和铜的行为。考察了液固比、硫酸浓度、搅拌速度、浸出时间和温度五个主要因素对锌和铜回收率的协同和单独影响。为此，分别建立了两个 2F1 模型，其 R 值分别为 0.9341 和 0.8693，用于描述铜和锌浸出效率与有效项之间的关系。结果表明，浸出过程受各因素之间交互作用的显著影响。在所研究的范围内，所有因素的增加都会提高浸出回收率。然而，回收率几乎与搅拌速度无关，表明表面化学反应是浸出动力学的控制步骤。还发现，温度的线性效应、浸出时间与液固比的交互效应以及硫酸浓度与搅拌速度的交互效应对铜的浸出率影响最大。此外，温度的线性效应以及温度与搅拌速度和液固比的交互效应被确定为锌回收率的最有效因素。此外，通过使用适宜性函数方法进行了优化，在酸浓度为 10%、搅拌速度为 300rpm、液固比为 10mL/g、温度为 35°C 和浸出时间为 75min 的条件下，获得了最高的铜（73.95%）和锌（81.02%）回收率。
