超声波强化浸出含铟锌渣及浸出液提铟、制取纳米多孔ZnFe2O4电极材料的基础研究

In this project, hydrometallurgy zinc residue (indium-bearing zinc residue) is selected as research object and sulfuric acid is selected as leaching agent. Aming at the problems of low indium and zinc recovery rate from indium-bearing zinc residue and the disadvantages of severe operational condition, high raw material consuming, high pollution and energy consuming in high temperature acid leaching method which is now widely used for the leaching of indium-bearing zinc residue, ultrasonic is introduced into the leaching process of indium-bearing zinc residue instead of high temperature acid leaching method. In particular, by comparing reaction kinetics and the changes of microstruture and properties of indium-bearing zinc residue before and after normal conditional leaching and ultrasonic assistant leaching, and combining with the first-principles calculations, the essential mechanism of leaching reaction and the underlying reason for ultrasonic intensified leaching will be reaveled. Aming at the problems of difficulty in separating Zn and Fe ions in leaching solution, nonutilization of Fe resources, and pollutions of low concentration SO2 and iron oxide residue produced in the process of indium leaching from jarosite residue, a new technology that without separating Zn and Fe ions and directly using these Zn and Fe ions in the purified liquid after indium extraction to prepare nano porous ZnFe2O4 electrode material with high additional value is proposed. The results of this project can perfect the leaching mechanism of hydrometallurgy zinc residue and the ultrasonic assistant leaching mechanism, which can provide theoretical basis for its high-efficient leaching. This project also provides a new way for the higher value utilizations of Zn and Fe resources, simplifying the process of indium extraction from indium-bearing zinc residue, and decreasing pollution.

本项目以湿法炼锌渣（含铟锌渣）为研究对象，以硫酸为浸出剂，针对含铟锌 渣中铟、锌浸出率低，而目前采用的高温高酸浸出存在操作条件苛刻、原材料消耗大、污染 大、能耗高等缺点，将超声波引入到含铟锌渣的浸出过程中替代高温高酸浸出,通过对比超 声波强化浸出和常规浸出反应动力学、浸出前后含铟锌渣的结构特性变化并结合第一性原理 计算从本质上分析和揭示含铟锌渣的浸出反应机理以及超声波强化浸出的作用机制。针对浸 出液中锌、铁分离困难，铁资源无法充分利用，铁矾渣提铟产生的低浓度二氧化硫和氧化铁 渣污染环境等问题，提出一种无需锌铁分离直接利用提铟净化液中的锌、铁离子制备高附加 值的纳米多孔铁酸锌电极材料的新工艺。项目研究结果可完善含铟锌渣在酸性体系中的浸出 机理、超声波强化浸出机制和动力学理论，为其高效浸取提供理论依据；同时该研究为简化含铟锌渣提铟流程、降低污染以及锌、铁资源的高值化利用提供了一条新的途径。

本项目以含铟锌渣为研究对象，以硫酸为浸出剂，针对含铟锌渣中铟、锌浸出率低，且目前采用的浸出工艺存在操作条件苛刻、原材料消耗大、污染大、能耗高等缺点，将超声波引入到含铟锌渣的浸出过程中，研究了含铟锌渣的浸出机理和超声波强化铟、锌浸出工艺及动力学。研究发现：常规酸浸与超声波酸浸过程相似，颗粒可以近似看作是整体溶解，常规浸出慢的主要原因在于渣中主要载铟/锌物相ZnFe2O4晶体内部含有稳定的Zn–O共价键；超声波引入能显著提高铟、锌的浸出率，其作用机理在于超声波的空化作用创造了新的活性表面，加快了浸出反应速率，使浸出反应的表观活化能和反应级数降低。针对浸出液中锌、铁分离困难，铁资源无法充分利用，污染环境等问题，首先以纯的锌盐和铁盐为原料，探索研究了均相沉淀法、化学沉淀法、蔗糖辅助烧结法制备高性能锂离子电池用铁酸锌基电极材料；在此研究基础上，直接利用浸出液制备出了具有应用前景的高性能纳米多孔铁酸锌以及纳米铁酸锌/氧化铁锂离子电池用负极材料。其中制备的纳米铁酸锌/氧化铁复合电极材料在1000 mAg-1充放电电流密度下，经过900次充放电循环后放电比容量保持在1000 mAhg-1；在大电流密度5000 mAg-1下仍能获得535 mAhg-1的放电比容量。制备的纳米多孔铁酸锌在500 mAg-1充放电电流密度下300次充放电循环后放电比容量为1371 mAhg-1，在电流密度1000 mAg-1下900次充放电循环后放电比容量为1140 mAhg-1。电化学反应动力学和储荷机理分析发现，赝电容行为对纳米铁酸锌电极的可逆容量有显著的贡献。本项目的研究结果进一步完善了含铟锌渣浸出机理、超声波强化浸出机理和动力学理论，为高效浸取含铟锌渣提供理论依据和设计模型，同时该研究对含铟锌渣酸浸液中有价金属的综合利用提供一条新的途径，具有重要的理论意义和实际应用参考价值。