臭氧氧化改性碳纳米管对铀的吸附性能

通过臭氧氧化改性方法制备含有大量含氧官能团的改性碳纳米管(CNT)。采用有机元素分析、X射线光电子能谱(XPS)元素分析以及Boehm滴定法分别测得样品的表面含氧量、总含氧量以及不同含氧官能团含量,并对产物的比表面积、孔体积和孔径进行测定。结果表明,改性后含氧功能团数量增加了3~7倍,并且这种臭氧改性技术受温度影响显著。然后,考察了改性CNT对铀的吸附性能,对吸附条件进行优化。结果表明,未经改性的CNT样品的吸附效果较差,铀去除率仅为78.0%,而改性后的CNT对铀的吸附效果有显著提高,铀去除率高达95.0%以上,表明含氧量的增加显著提高了改性物对铀的吸附效果。

Adsorption Performance of Carbon Nanotube Oxidized by Ozone for Uranium

Carbon nanotubes(CNT) with plenty of oxygen containing functional groups were successfully prepared by the ozone oxidation method. The contents of oxygen containing functional groups in the samples were determined by organic element analysis, XPS element analysis and the Boehm titration. The special surface area, pore volume and pore diameter were measured. Results show that the contents of oxygen containing functional groups increase 3-7 times after modification. This ozone modification technique is significantly influenced by temperature. The adsorption performance of the modified CNT for uranium from aqueous solutions was investigated, and the optimum adsorption conditions were obtained. Results show that CNT without modification has poor adsorption efficiency, and the maximum removal rate of uranium is only 78.0%. The adsorption property of the modified CNT is significantly improved due to the increasing contents of oxygen containing functional groups, and the maximum removal rate of uranium is up to above 95.0%.