Investigation of interaction between U(VI) and carbonaceous nanofibers by batch experiments and modeling study
Investigation of interaction between U(VI) and carbonaceous nanofibers by batch experiments and modeling study
复制标题
通过批量实验和模型研究研究U(VI)与碳质纳米纤维之间的相互作用
DOI：
10.1016/j.jcis.2015.08.073
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发表时间：
2015
影响因子：
9.9
通讯作者：
Wang Xiangke
中科院分区：
文献类型：
--
作者：
Zhang Rui;Chen Changlun;Li Jie;Wang Xiangke
以碲纳米线为模板，以葡萄糖为碳源，采用水热碳化法合成了碳质纳米纤维（CNFs）。通过批量吸附实验、双层模型 (DLM) 和 X 射线光电子能谱 (XPS) 相结合，研究了 CNFs 上 U(VI) 的吸附容量和吸附机制。通过考虑以下表面配合物，对吸附边缘进行了很好的建模：强位点上的三键SOUO2+、三键SOUO2OH、三键SOUO2(OH)2−和三键SOUO2(OH)32−以及弱位点上的三键XOUO2OH和三键XOUO2+（S和X代表表面）。 DLM 参数可以很好地拟合吸附等温线。在XPS中观察到A型（三键SOUO2OH和三键XOUO2OH）和B型（三键SOUO2+和三键XOUO2+）之间的差异，因为前者的结合能较低，而后者的结合能较高。解吸和循环实验表明，CNFs在普通钠盐存在下，五轮内具有良好的重复使用性和稳定性。当与蒙脱石共存时，CNF 可以通过伪二级动力学过程将吸附的铀提取到其表面。 CNF作为一种新型的环境功能纳米材料，在分离和废水修复领域应受到更多关注。
Carbonaceous nanofibers (CNFs) were synthesized using tellurium nanowires as a template and using glucose as carbon source by the hydrothermal carbonization method. The sorption capacity and mechanism of U(VI) on CNFs were investigated by a combination of batch sorption experiments, the double layer model (DLM) and X-ray photoelectron spectroscopy (XPS). The sorption edges were modeled well by considering the following surface complexes: triple bondSOUO2+, triple bondSOUO2OH, triple bondSOUO2(OH)2−and triple bondSOUO2(OH)32−on the strong site as well as triple bondXOUO2OH and triple bondXOUO2+on the weak one (S and X represent surface). The sorption isotherms could be well fitted by the DLM parameters. The difference between type A (triple bondSOUO2OH and triple bondXOUO2OH) and type B (triple bondSOUO2+and triple bondXOUO2+) was observed in XPS because the former species are of low binding energy while the latter are of high one. Desorption and recycle experiments showed that CNFs had good reusability and stability in the present of common sodium salts within five rounds. When co-existing with montmorillonite, CNFs could extract the sorbed uranium onto their surface by a pseudo-second order kinetic process. As a new sort of environmental functional nanomaterials, CNFs should be paid more attention in the area of separation and wastewater remediation.