新型聚合物网络水凝胶制备及其吸附性能研究

Preparation of novel polymer network hydrogel and its adsorption performance

为同步吸附复合污水中的重金属离子及含酚化合物,利用半胱氨酸接枝改性β-环糊精(β-CD)得到巯基接枝β-环糊精(β-CD-Cys),氧化偶合反应巯基得到二硫键交联型新型聚合物网络水凝胶。通过红外光谱(IR)、核磁共振谱(1H NMR)结合扫描电镜(SEM)表征其中间及最终产物,考察新型水凝胶热稳定性能和溶胀性能,并测试其分子-离子同步识别性能。结果表明,设计的反应路线合理,成功制得新型聚合物网络水凝胶,该新型水凝胶具有良好的热稳定性、溶胀性。同步去除重金属离子和含酚污染物的性能较优,对Cu^2+、Pb^2+、Cr^3+、Zn^2+和苯酚的最大吸附量分别为172.16、465.56、65.98、187.55、46.55mg×g^-1。新型聚合物网络水凝胶对重金属离子及苯酚的吸附符合准二级动力学模型,吸附等温线符合Langmuir吸附等温线。

In order to simultaneously adsorb heavy metal ions and phenolic compounds in composite wastewater,β-cyclodextrin(β-CD) was modified with cysteine to obtain sulfhydryl grafted β-cyclodextrin(β-CD-Cys), and sulfydryl was then oxidized to prepare disulfide-crosslinking novel polymer network hydrogel. The intermediate and final products were characterized by infrared spectroscopy(IR), nuclear magnetic resonance spectroscopy(1H NMR) and scanning electron microscopy(SEM). The thermal stability and swelling properties of the novel hydrogels were investigated and their molecular-ion synchronous recognition performance was tested. The results show that the simple reaction route is reasonable to prepare novel polymer network hydrogel, which has good thermal stability and swelling ability. The performance of simultaneous removal of heavy metal ions and phenol-containing contaminants was superior. The maximum adsorption amounts of Cu^2+, Pb^2+, Cr^3+, Zn^2+ and phenol were 172.16, 465.56, 65.98, 187.55 and 46.55 mg×g^-1, respectively. The adsorption processes followed the quasi-secondary kinetic model, and the adsorption isotherm conformed to the Langmuir adsorption isotherm.