酸盐分离技术在镍电积阳极液中的应用

Application of Separation Technology of Acid and Salt in Nickel Anodic Electrolyte

目前酸盐分离技术主要有树脂吸附法、离子交换法和膜分离技术三大类,但将其应用于镍湿法冶炼中镍电积阳极液的报道较少。总结了三大类酸盐分离技术的原理和应用,并分别采用树脂吸附法、扩散渗析法、特种纳滤膜和电渗析结合的方法对镍电积阳极液进行酸盐分离试验。结果表明,三种方法对镍电积阳极液均有一定的分离效果,其中树脂吸附法易饱和,需反洗再生,造成体积膨胀;扩散渗析法对硫酸的回收率在80%以上,镍的截留率在90%以上,但回收的硫酸浓度较低,同样存在体积膨胀问题;特种纳滤膜和电渗析结合法对镍离子的截留率可达90%以上,氢离子去除率可达70%以上,同时浓缩后的氢离子浓度可提高400%以上,镍离子浓度可提高500%以上,淡化液中各种离子浓度小于50 mg/L,可用作纯水,并且该方法不会造成系统体积膨胀,具有工业化应用价值。

At present,there are three main types of acid and salt separation technology,i.e.,resin adsorption method,ion exchange method and membrane separation technology,but there are few reports about its application on nickel anodic electrolyte of hydrometallurgy.The principles and applications of three types of acid and salt separation technologies were summarized,and the acid and salt separation experiment of nickel anodic electrolyte were carried out by resin adsorption,diffusion dialysis,special nanofiltration membrane and electrodialysis combined methods.The results show that the three methods have a certain separation effect on nickel anodic electrolyte,the resin adsorption method is easy to saturate and requires backwashing to regenerate,which may cause volume expansion;Diffusion dialysis method has a recovery rate of 80%above for sulfuric acid and a rejection rate of 90%above for nickel,but the concentration of recovered sulfuric acid is low,which can also cause volume expansion;The combined method of special nanofiltration membrane and electrodialysis has a rejection rate of 90%above for nickel ions,and a removal rate of hydrogen ions of 70%above.At the same time,the concentration of hydrogen ions after concentration can be raised by more than 400%,and the concentration of nickel ions can be raised by 500%,the concentration of various ions in desalination solution is less than 50 mg L,which can be used as pure water,and this method will not cause system volume expansion,which has industrial application value.