电渗析法回收含Cu、Fe、Ni硫酸溶液中的硫酸

Acid Recovery from Synthetic Cu、Fe、Ni Solution Using Electrodialysis

本文研究了用电渗析法从含铜、铁、镍离子的酸性溶液中回收硫酸的行为。测定了电流密度、给液的初始酸浓度、金属离子类别和浓度对硫酸回收效率的影响，实验结果表明：给液中初始硫酸浓度为１０～２００ｇ／ｌ，金属离子浓度４～５０ｇ／ｌ时，硫酸可以通过电渗析法有效地进行回收，有少量金属离子随同硫酸一起进入产物液．对产物液的污染程度为：铜＞＞铁＞镍．这一现象可由实验所测得的膜电阻：铜＜铁＜镍得到解释。电渗析过程中硫酸从给液到产物液的转移效率与给液中金属离子类型无关．而与给液的初始酸浓度和电流密度有关，能量消耗随电流密度的增加而增大，而与给液的初始酸浓度无关。

Electrodialysis (ED) has been used to recover H2SO4 from synthetic solutions containing Cu, Ni and Fe. The effect of current density, feed acid concentration and type and concentration of metal ions on the efficiency of acid recovery has been measured. Sulphuric acid can be recovered efficiently by electrodialysis for acid concentrations from 10 to 200 g/l and metal concentrations4 to 50 g/l. During the electrodialysis process a small amount of metal is transported with the acid into product stream. The level of contamination is in the order Cu>>Fe>Ni. This agrees well with the observed order of membrane electrical resistances: Cu<Fe<Ni. It was found that acid transfer efficiency is largely independent of the type of metal ion in the dialysate, and transfer efficiency is most strongly effected by the initial acid concentration and current density. The energy consumption increases with increasing current density, but is unaffected by increasing acid concentration in the dialysate. The application of commercial electrodialysers for acid recovery is discussed.