壳聚糖衍生物的制备及其对Cr(Ⅵ)离子的吸附  

Adsorption of Cr(Ⅵ) to Prepared Chitosan Ramifications

作　　者：刘小鹏[1] 张剑波[1] 王维敬[1] 李凤[1] 

机构地区：[1]北京大学环境学院环境科学系,北京100871

出　　处：《北京大学学报（自然科学版）》2003年第6期880-887,共8页Acta Scientiarum Naturalium Universitatis Pekinensis

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 3mgCr(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)× 10 5g mol的范围内存在一个吸附最大值。Crosslinked chitosan, butylchitosan and O-carboxymethyl chi t osan were prepared by chemical method respectively, and some chitosan with low m olar 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 ti me is 2?h; 3?mg Cr(Ⅵ) can be adsorbed by a gram chitosan and the adsorpti o n rate can be up to 90 %. All the adsorption abilities of crosslinked chitosan, butylchitosan and O-carboxymethyl chitosan are stronger than that of original c hitosan. For examples, crosslinked chitosan may reach the adsorption saturation in 1?h; the optimum pH of adsorption for butylchitosan is near 5.0, so it is mo r e available in acidic condition.After radiation degradation, chitosan has a ra nge of best adsorption in molar mass of (0.4～0.8) ×10 5?g/mol.

关 键 词：壳聚糖衍生物 吸附 Cr(Ⅵ) 水处理 

分 类 号：O647.3[理学—物理化学]