N-甲基咪唑固载化离子交换树脂对砷的吸附分离

Adsorption and Separation of As(Ⅴ) with N-Methylimidazolium Functionalized Anion Exchange Resin

研究了N-甲基咪唑阴离子交换树脂(RCl)对水中As(Ⅴ)的吸附。RCl有较高的热稳定性和化学稳定性,并且可适用于较宽的酸度范围(pH 1～12)。RCl可去除水中低浓度的As(Ⅴ)。树脂和As(Ⅴ)发生阴离子交换反应,此反应在60 min时快速达到平衡,为了保证吸附反应更完全,所有吸附实验均进行2 h。吸附数据符合Langmuir吸附等温方程,RCl对As(Ⅴ)的最大吸附容量为67.2 mg/g。随着温度的升高,吸附率逐渐增大,表明此阴离子交换反应是吸热反应。对负载As?的RCl树脂用0.1 mol/L HCl进行解吸附,解吸附率达到99.46%,树脂可以再生并且重复利用。

The adsorption behavior of As（V） with N-methylimidazolium functionalized strongly basic anion exchange resin in C1-form （RC1） was systematically investigated. The RC1 had high thermal stability and good ehemical stability under the experimental conditions, and it could be used in the wide pH range from 1 to 12. So RC1 was very suitable for removing As（V） from water at a low coneentration level. The adsorption mechanism was in aeeord with anion exehange meehanism. The adsorption equilibrium was attained at 60 min. To make sure true equilibrium was established, all the subsequent adsorption experiments were carried out for 2 h. The adsorption data for RC1 was consistent with the Langmuir isotherm equation, and the maximum adsorption capacity of As（V） was 67.2 mg/g. The adsorption percentage increased slightly with increasing temperature, which showed that the reaction was endothermic. RC1 was easily regenerated by 0. 1 mol/L HC1, and the desorption pereentage was up to 99.46%.