离子交换法从硫酸亚铁溶液中分离镍实验研究

本文针对高铁低镍硫酸亚铁溶液中镍铁分离困难的生产实际，采用离子交换技术对硫酸亚铁溶液中的镍铁分离进行了研究。通过条件实验考察了树脂装填量、吸附前液pH值、吸附时间、镍离子浓度等对镍铁分离效果的影响。结果表明，CH-90树脂对含镍硫酸亚铁溶液中镍有明显的优先选择性，树脂对镍的工作交换容量为15 mg/g。经过离子交换树脂处理，溶液中的铁镍摩尔比由处理前的17:1最高可以提高到93:1，镍去除率达到87%，处理后溶液含镍小于0.3 g/L，具有良好的分离效果。改变初始浓度和吸附反应时间，探究了树脂的吸附等温线和吸附动力学过程，发现树脂符合Langmuir吸附和准二级动力学方程，说明吸附属于单分子层吸附和定点吸附，吸附过程主要是离子交换控制的。

Experimental study on nickel removal in ferrous sulphate solution by ion exchange method

Based on the problem of nickel remove from ferrous sulphate solution with low nickel content, it was investigated by ion exchange process in this paper. Different factor, such as resin filling capacity, time, pH and so on, was investigated to explore the performance of nickel remove from ferrous sulphate solution by designed experiments. The results indicate that priority selectivity for nickel is presented in ferrous sulphate solution after resin treatment and the operating capacity of CH-90 resin is 0.7-0.95 mol/L. Iron/nickel molar ratio is increased from 17:1 to 93:1 after resin. Removal rate on nickel reached 87% and nickel content is reduced to 0.3 g/L. In other words, nickel is removed effectually from ferrous sulphate solution. The adsorption isotherms and adsorption kinetics were evaluated by changing the initial concentration and adsorption reaction time．It was found that the resin was in line with the Langmuir adsorption isotherm,and met the quasi-second-order kinetic equation．Results showed that the adsorption of Ni_²⁺ can be classified as monolayer adsorption and site-specific adsorption,and the adsorption process was mainly controlled by ion-exchange。