Zheng Xuemei, Li Jinjing, Ma Aiyuan, Liu Bingguo
School of Chemistry and Materials Engineering, Liupanshui Normal University, Liupanshui 553004, China.
Key Laboratory of Unconventional Metallurgy, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China.
Materials (Basel). 2023 Jul 20;16(14):5132. doi: 10.3390/ma16145132.
Metallurgical slag and dust (MSD) are abundant Zn-containing secondary resources that can partially alleviate the shortage of zinc minerals, with hazardous characteristics and a high recycling value. In this work, the process conditions of recycling Zn from MSD materials leaching by ammonium acetate (NH-CHCOONH-HO) were optimised using response surface methodology (RSM). The influences of liquid/solid ratio, stirring speed, leaching time, total ammonia concentration, and the interactions between these variables on the Zn effective extraction rate during the ammonium acetate leaching process were investigated. Additionally, the predicted regression equation between the Zn effective extraction rate and the four affecting factors was established, and the optimal process parameters were determined with a stirring speed of 345 r/min, leaching temperature of 25 °C, [NH]/[NH] of 1:1, total ammonia concentration of 4.8 mol/L, liquid/solid ratio of 4.3:1, and leaching time of 46 min. The Zn effective extraction rates predicted by the proposed model and the measured values were 85.25% and 84.67%, respectively, with a relative error of 0.58% between the two values, indicating the accuracy and reliability of the proposed model. XRD and SEM-EDS analysis results showed that ZnSiO, ZnS, and ZnFeO were among the main factors affecting the low extraction rate of zinc from metallurgical slag dust. This work established a new technology prototype for the effective and clean extraction of zinc resources, which can provide new routes to effectively utilise Zn-containing MSD materials and lay a foundation for developing other novel techniques for recycling Zn from Zn-containing secondary resources.
冶金炉渣和粉尘（MSD）是富含锌的二次资源，可部分缓解锌矿物短缺问题，具有有害特性但回收价值高。在本工作中，采用响应面法（RSM）优化了用醋酸铵（NH₄CH₃COONH₄·H₂O）从MSD材料浸出中回收锌的工艺条件。研究了液固比、搅拌速度、浸出时间、总氨浓度以及这些变量之间的相互作用对醋酸铵浸出过程中锌有效提取率的影响。此外，建立了锌有效提取率与四个影响因素之间的预测回归方程，并确定了最佳工艺参数为搅拌速度345 r/min、浸出温度25℃、[NH₃]/[NH₄⁺]为1:1、总氨浓度4.8 mol/L、液固比4.3:1和浸出时间46 min。所提模型预测的锌有效提取率和测量值分别为85.25%和84.67%，两者相对误差为0.58%，表明所提模型的准确性和可靠性。XRD和SEM-EDS分析结果表明，ZnSiO₄、ZnS和ZnFe₂O₄是影响冶金炉渣粉尘中锌提取率低的主要因素。本工作建立了一种有效清洁提取锌资源的新技术原型，可为有效利用含锌MSD材料提供新途径，并为开发从含锌二次资源中回收锌的其他新技术奠定基础。
