College of Ocean, Harbin Institute of Technology at Weihai, Weihai, PR China.
J Hazard Mater. 2010 Sep 15;181(1-3):908-15. doi: 10.1016/j.jhazmat.2010.05.098. Epub 2010 Jun 1.
This paper reports the optimization of the process parameters for recovery of zinc from hot galvanizing slag in an anion-exchange membrane electrolysis reactor. The experiments were carried out in an ammoniacal ammonium chloride system. The influence of composition of electrolytes, pH, stirring rate, current density and temperature, on cathodic current efficiency, specific power consumption and anodic dissolution of Zn were investigated. The results indicate that the cathode current efficiency increases and the hydrogen evolution decreased with increasing the cathode current density. The partial current for electrodeposition of Zn has liner relationship with omega(1/2) (omega: rotation rate). The highest current efficiency for dissolving zinc was obtained when NH(4)Cl concentration was 53.46 g L(-1) and the anodic dissolution of zinc was determined by mass transfer rate at stirring rate 0-300 r min(-1). Increase in temperature benefits to improve CE and dissolution of Zn, and reduce cell voltage. Initial pH of electrolytes plays an important role in the deposition and anodic dissolution of Zn. The results of single factor experiment show that about 50% energy consumption was saved for electrodeposition of Zn in the anion-exchange membrane electrolysis reactor.
本文报告了在阴离子交换膜电解槽中从热镀锌渣中回收锌的工艺参数优化。实验在氨性氯化铵体系中进行。考察了电解液组成、pH 值、搅拌速度、电流密度和温度对阴极电流效率、比能耗和锌阳极溶解的影响。结果表明,随着阴极电流密度的增加,阴极电流效率增加,析氢减少。锌的部分电流与 ω(1/2)(ω:转速)呈线性关系。当氯化铵浓度为 53.46 g/L 时,获得了最高的锌溶解电流效率,在搅拌速度为 0-300 r/min 时,锌的阳极溶解由传质速率决定。升高温度有利于提高 CE 和锌的溶解,降低槽压。电解液初始 pH 值对锌的沉积和阳极溶解有重要影响。单因素实验结果表明,在阴离子交换膜电解槽中进行锌电沉积可节省约 50%的能耗。