除镍离子交换树脂的优选及其效能的研究

为优选除Ni~(2+)交换树脂,采用电镀镍废水(Ni~(2+)的质量浓度为80 mg/L)研究了5种阳离子交换树脂对Ni~(2+)的吸附等温式和吸附动力学,考察了其对电镀镍废水中Ni~(2+)的吸附交换容量、吸附交换速率、再生性能以及废水中共存离子对树脂处理电镀镍废水效能的影响。结果表明,在120 min内5种阳离子树脂对Ni~(2+)的吸附基本达到平衡,吸附等温线均符合Freundlich吸附,吸附动力学均遵循准二级动力学方程;KP752和CH-90树脂对Ni~(2+)吸附交换容量分别为22.421和22.831 mg/g,吸附效果最好,并且2种树脂对Ni~(2+)的回收率都可达80%以上;共存的Ca~(2+)、Mg~(2+)会显著影响CH-90树脂吸附Ni~(2+)的效果,而对KP752树脂的影响较小。

Research on optimization and efficiency of ion exchange resin for Ni2+removal

In order to select the best ion exchange resin for Ni2+ removal, the adsorption isotherms and adsorption kinetics of 5 kinds of cation exchange resins on Ni2 + were studied using nickel electroplating wastewater (mass concentration of Ni2+ was 80 mg/L). The effect of the above resins on adsorption exchange capacity, exchange adsorption rate and regeneration rate of Ni2 + in nickel electroplating wastewater was investigated. Meanwhile, the effect of coexisting ions in wastewater on the treatment of nickel electroplating wastewater by resins was studied also. The results showed that, the adsorption of Ni2+by 5 kinds of cation resins reached equilibrium in 120 min, the adsorption isotherms were in accordance with the Freundlich adsorption;and the adsorption kinetics fit the pseudo-second order kinetic equation. The adsorption exchange capacities of KP752 and CH-90 resin for Ni2+ were 22.421 and 22.831 mg/L respectively, which showed the best adsorption effect. More than that, the recovery rate of Ni2+by the said two kinds of resins both above 80%. The coexistence of Ca2+ and Mg2+ in wastewater could significantly affect the adsorption efficiency of CH-90 resin on Ni2+, however, its influence on KP752 resin was small.