【摘要】 采用低温等离子体法将O-磷酸乙醇胺(O-PEA)接枝到多壁碳纳米管表面(MWCNTs),并使用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)和拉曼光谱(Raman)表征改性前后的MWCNTs的物化性质.通过静态吸附实验研究改性碳纳米管对溶液中U(Ⅵ)的吸附容量,同时,还研究了吸附时间、pH、离子强度和温度对吸附性能的影响.结果表明,通过低温等离子体法改性后的MWCNTs(PTMWCNTs-4)对U(Ⅵ)的吸附性能最好,其吸附容量大约是未改性MWCNTs吸附量的3倍.改性后的MWCNTs吸附速率更快. PTMWCNTs-4对U(Ⅵ)的吸附在pH<7.0条件下不受离子强度影响,属于内层络合机理;而在pH>7.0条件下受离子强度影响,属于外层络合机理或离子交换.热力学数据表明,吸附过程放热且可自发进行.本文为U(Ⅵ)的有效去除提供了一种新型环保的改性方法.更多还原

【Abstract】 Multiwalled carbon nanotubes(MWCNTs) grafted O-phosphoethanolamine(O-PEA) were prepared by nonthermal plasma technology for U(VI) adsorption. The modified MWCNTs were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), Fourier transform infrared spectrometer(FTIR), X-ray diffraction(XRD) and Raman spectra. The static adsorption study was carried out and the parameter effect on the adsorption capacity including contact time, pH, ionic strength and temperature were investigated. The results indicate that U(Ⅵ) adsorption on MWCNTs(PTMWCNTs-4) is the best, about three times that of the raw MWCNTs. The modified MWCNTs have a faster adsorption rate. The adsorption of U(Ⅵ) on PTMWCNTs-4 is dominated by the innersphere surface complexation at p H<7.0, whereas by the outer-sphere surface complexation or ion exchange at pH>7.0.Thermodynamic data show that the adsorption process is an exothermic and spontaneous process. This work provides a new environmental modification method for the efficient removal of U(Ⅵ).更多还原