Abstract: With the static and dynamic experiments, the adsorption behavior of Pb2+ on D418 resin was studied, and the adsorption process analyzed from the aspects of thermodynamics and kinetics, and the adsorption mechanism analyzed by infrared spectroscopy. The experimental results showed that in the studied condition range, the equilibrium adsorption data fitted to both Langmuir and Freundlich isotherms. The adsorption of Pb2+ on the resin was an endothermic process. Kinetic analysis showed that the adsorption rate was mainly governed by liquid film diffusion, with the increment of initial solution concentration, the adsorption rate would decrease. The static saturated adsorption capacity was 375 mg/g (based on resin) at 313 K, and the desorption rate could reach 97% by 3 mol/L nitric acid at 298 K. The optimal quantity of regenerant was five bed volumes. The resin can be used in wastewater treatment and enrichment of lead.

Key words: lead ion, macroporous chelating resin, adsorption, desorption, mechanism

摘要： 通过静态和动态吸附实验，研究了Pb2+在D418树脂上的吸附行为，从热力学和动力学方面对吸附过程进行了分析，并通过红外光谱探讨了吸附机理. 结果表明，在所研究的条件范围内，Pb2+在D418树脂上的吸附是吸热过程，同时符合Freundlich和Langmuir等温吸附方程；液膜扩散为Pb2+在D418树脂上吸附速率的主要控制步骤，随着溶液初始浓度的增大，吸附速率逐渐减小；313 K温度下树脂的静态饱和吸附容量为375 mg/g，在298 K下用3 mol/L的硝酸作为解吸剂，解吸率可达97%；最佳的解吸剂用量为5倍床层体积. 该树脂吸附操作简单，易再生，不产生二次污染，有望用于含铅废水的治理及铅的富集.

关键词: 铅离子, 大孔螯合树脂, 吸附, 解吸, 机理