Grudinsky Pavel, Pankratov Denis, Kovalev Dmitry, Grigoreva Darya, Dyubanov Valery
Laboratory of Physical Chemistry and Technology of Iron Ore Processing, A.A. Baikov Institute of Metallurgy and Materials Science, Russian Academy of Science, 49 Leninsky Prosp., 119334 Moscow, Russia.
Department of Radiochemistry, Faculty of Chemistry, Lomonosov Moscow State University, 1-3 Leninskiye Gory, 119991 Moscow, Russia.
Materials (Basel). 2021 Sep 2;14(17):5020. doi: 10.3390/ma14175020.
Zinc plant residue (ZPR) is a secondary material generated during hydrometallurgical zinc production that contains considerable contents of valuable elements such as Zn, Cu, Fe, Pb, Cd, Ag, In, Ga, Tl. Zinc, copper and accompanying elements in ZPR are in different minerals, mainly in the ferrites. A promising approach for recycling ZPR is the sulfating roasting using iron sulfates followed by water leaching. In this study, the composition of ZPR and the obtained products were thoroughly investigated by various methods including X-ray diffraction analysis (XRD), chemical phase analysis and Mössbauer spectroscopy. The effect of temperature, amount of iron sulfates and roasting time on the conversion of valuable metals into a water-soluble form was thermodynamically and experimentally studied both using pure ferrites and ZPR. Based on the results of time-resolved XRD analysis and synchronous thermal analysis (STA), a mechanism of the sulfation roasting was elucidated. The rate-controlling step of zinc and copper sulfation process during the ZPR roasting was estimated. The sulfating roasting at 600 °C during 180 min with the optimal Fe(SO)∙9HO addition followed by water leaching enables to recover 99% Zn and 80.3% Cu, while Fe, Pb, Ag, In, Ga retained almost fully in the residue.
锌厂残渣（ZPR）是湿法冶金锌生产过程中产生的一种二次物料，含有大量诸如锌、铜、铁、铅、镉、银、铟、镓、铊等有价元素。ZPR中的锌、铜及伴生元素存在于不同的矿物中，主要是铁氧体矿物。一种回收ZPR的可行方法是使用硫酸铁进行硫酸化焙烧，随后进行水浸出。在本研究中，通过包括X射线衍射分析（XRD）、化学相分析和穆斯堡尔谱等多种方法对ZPR及其所得产物的组成进行了深入研究。利用纯铁氧体和ZPR从热力学和实验两方面研究了温度、硫酸铁用量和焙烧时间对有价金属转化为水溶性形式的影响。基于时间分辨XRD分析和同步热分析（STA）的结果，阐明了硫酸化焙烧的机理。估算了ZPR焙烧过程中锌和铜硫酸化过程的速率控制步骤。在600℃下焙烧180分钟，加入最佳量的Fe₂(SO₄)₃·9H₂O，随后进行水浸出，能够回收99%的锌和80.3%的铜，而铁、铅、银、铟、镓几乎全部保留在残渣中。
