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℃、p H＝4.0、吸附时间为45 min的条件下，对U （Ⅵ）浓度为5 mg／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（0.05 mg／L ）。吸附U （Ⅵ）的α‐酮戊二酸改性壳聚糖可用8％的NaO H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—COO H是U （Ⅵ）的主要结合位点。%A kind of α‐ketoglutaric acid modified chitosan (KMCS) was synthesized with the reaction of α‐ketoglutaric acid and chitosan to obtain Schiff base and with the reduc‐tion 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 5 mg/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 the national emission standard (0.05 mg/L) .The KMCS can be regenerated with the solu‐tion 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 struc‐ture .FT‐IR analysis demonstrates that —COOH groups of KMCS are the main binding sites of U (Ⅵ) .
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