ABSTRACT

Heavy metal pollution is extraordinary critical, so it is urgent to develop an effective adsorbent to dispose of such pollution. Modified chitosan was combined with polyacrylic acid to form N-carboxymethyl chitosan hydrogel (NCS-hydrogel) adsorbent. The morphology and structure of NCS-hydrogel were analyzed and identified by infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis and other characterization methods. NCS-hydrogel adsorption was used to treat water pollution of Cu, Cd and Pb ions, and the influencing factors of adsorption performance were studied. The intrinsic mechanism of adsorption process was discussed by thermodynamic, kinetic and isotherm models. The results show that the adsorption process of metal ions by NCS-hydrogel meets the spontaneous monolayer chemisorption, and the adsorption process is accompanied by heat release.

摘要

重金属污染异常严重，因此迫切需要开发一种有效的吸附剂来处理这种污染。改性壳聚糖与聚丙烯酸结合形成N-羧甲基壳聚糖水凝胶（NCS-hydrogel）吸附剂。采用红外光谱、扫描电镜、热重分析等表征手段对NCS-水凝胶的形貌和结构进行了分析鉴定。采用NCS-水凝胶吸附法处理Cu、Cd和Pb离子的水污染，研究了吸附性能的影响因素。通过热力学、动力学和等温线模型讨论了吸附过程的内在机理。结果表明，NCS-水凝胶对金属离子的吸附过程符合自发的单层化学吸附，