中文摘要：

通过α-酮戊二酸与壳聚糖反应生成Schiff碱,再用NaBH4还原制备出α-酮戊二酸改性壳聚糖。采用FT-IR、XRD和SEM对其结构进行表征,研究其对水溶液中U（Ⅵ）的吸附行为,考察溶液初始pH值、吸附时间、温度等因素对其吸附水溶液中U（Ⅵ）效果的影响。结果表明,在35℃、pH=4.0、吸附时间为45min的条件下,对U（Ⅵ）浓度为5mg/L的水溶液中铀的去除率在99%以上,U（Ⅵ）的剩余浓度已达到国家排放标准（0.05mg/L）。吸附U（Ⅵ）的α-酮戊二酸改性壳聚糖可用8%的NaOH溶液进行解吸再生,解吸再生后的吸附剂对U（Ⅵ）的吸附效果未明显下降。SEM表明,α-酮戊二酸改性壳聚糖表面粗糙,呈现凹凸不平的多孔结构。FT-IR分析显示,α-酮戊二酸改性壳聚糖表面的—COOH是U（Ⅵ）的主要结合位点。

英文摘要：

A kind ofα-ketoglutaric acid modified chitosan（KMCS）was synthesized with the reaction ofα-ketoglutaric acid and chitosan to obtain Schiff base and with the reduction reaction by NaBH4.The structure of KMCS was characterized by FT-IR,XRD and SEM.The effects of initial pH,adsorption time,temperature and other factors on U（Ⅵ）adsorption on KMCS were investigated.The experimental results show that under the condition of 35 ℃,pH=4.0,adsorption time of 45 min,and U（Ⅵ）initial concentration of 5mg/L,the percentage removal of U（Ⅵ）adsorbed by KMCS is higher than 99%,which leads to the U（Ⅵ）concentration in the rest solution lower than thenational emission standard（0.05mg/L）.The KMCS can be regenerated with the solution of 8% NaOH,and there is no obvious decline after regeneration.The SEM images of the samples show that the KMCS has a rough surface and an uneven porous structure.FT-IR analysis demonstrates that—COOH groups of KMCS are the main binding sites of U（Ⅵ）.