离子交换与吸附

以自制亚胺二乙酸和羧酸基功能纤维为吸附材料,系统研究了有限浴及柱吸附条件下对Ni²⁺、Ca²⁺和Mg²⁺共存废水的选择性吸附性能。结果表明,与羧酸基纤维相比,亚胺二乙酸纤维具有很好的选择性吸附功能(有限浴条件下k_Ca^Ni和k_Mg^Ni分别为4.63和11.33;柱吸附条件下k_Ca^Ni和k_Mg^Ni分别为5.26和136.17),且对Ni²⁺的饱和吸附容量可达100mg/g左右;以2.5mol/L硫酸溶液为洗脱剂,Ni²⁺回收率≥94%;自制纤维经5次使用与再生循环后,对Ni²⁺吸附容量基本不变,具有良好的实际应用前景。

The selective adsorption and desorption properties of iminodiacetic acid fibers and carboxylic acid fibers for removal of Ni²⁺,Ca²⁺ and Mg²⁺ were studied by static and dynamic experiments.The results showed that adsorption selectivity of iminodiacetic acid fiber was better than that of carboxylic acid fibers(For iminodiacetic acid fiber,the selectivity coefficients of k_Ca^Ni and k_Mg^Ni were 4.63 and 11.33 respectively by static experiments,and k_Ca^Ni and k_Mg^Ni were 5.26 and 136.17 respectively by dynamic experiments).The operating adsorption capacity of Ni²⁺ with iminodiacetic acid fibers could be up to 100rag/g,and the recovery efficiency of Ni²⁺was over 94% when 2.5mol/L sulfuric acid was used as eluent.The iminodiacetic acid fibers showed excellent adsorption and desorption properties during 5 cycles of adsorption-regeneration,and good application prospect for the recovery of Ni²⁺ from industrial wastewater.