Abstract: Crosslinked chitosan, butylchitosan and O-carboxymethyl chitosan were prepared by chemical method respectively, and some chitosan with low molar mass was abtained by using γ-ray. Their characters of adsorption Cr(Ⅵ) were observed. For chitosan, the optimum pH of adsorption Cr(Ⅵ) is 5.0～6.0; the time is 2h; 3mg Cr(Ⅵ) can be adsorbed by a gram chitosan and the adsorption rate can be up to 90%. All the adsorption abilities of crosslinked chitosan, butylchitosan and O-carboxymethyl chitosan are stronger than that of original chitosan. For examples, crosslinked chitosan may reach the adsorption saturation in 1h; the optimum pH of adsorption for butylchitosan is near 5.0, so it is more available in acidic condition. After radiation degradation, chitosan has a range of best adsorption in molar mass of (0.4～0.8)×10⁵g/mol.

Key words: chitosan ramifications, adsorption, Cr(Ⅵ), wastewater treatment

摘要： 采用化学法对壳聚糖进行改性，分别制备了交联壳聚糖、丁烷基壳聚糖和O-羧甲基壳聚糖，用γ射线辐照降解制备了低摩尔质量的壳聚糖，研究了它们对废水中较难处理的污染物Cr(Ⅵ)的吸附情况，壳聚糖对Cr(Ⅵ)吸附的最佳pH值范围为5.0～6.0，最佳吸附时间大约为2h，每克壳聚糖可吸附约3mg Cr(Ⅵ)，吸附率最大可达90%以上。交联壳聚糖、丁烷基壳聚糖和低摩尔质量壳聚糖对Cr(Ⅵ)的吸附效果都比壳聚糖本身要好得多：交联壳聚糖吸附1h即可达到吸附饱和；丁烷基壳聚糖吸附Cr(Ⅵ)的最佳pH值出现在5.0附近，更能适应酸性环境；辐照降解后，壳聚糖在(0.4～0.8)×10⁵g/mol的范围内存在一个吸附最大值。

关键词: 壳聚糖衍生物, 吸附, Cr(Ⅵ), 水处理