Polyacrylonitrile/polypyrrole core/shell nanofiber mat for the removal of hexavalent chromium from aqueous solution.
Polyacrylonitrile/polypyrrole core/shell nanofiber mat for the removal of hexavalent chromium from aqueous solution.
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DOI：
10.1016/j.jhazmat.2012.11.020
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发表时间：
2013-01
影响因子：
13.6
通讯作者：
Jianqiang Wang;K. Pan;Qiwei He;B. Cao
中科院分区：
文献类型：
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作者：
Jianqiang Wang;K. Pan;Qiwei He;B. Cao
采用电纺法制备了聚丙烯腈/聚吡咯(PAn/PPy)核壳结构纳米纤维，并通过原位聚合反应去除水溶液中的六价铬(Cr6+)。衰减全反射傅里叶变换红外光谱(ATR-FTIR)和X射线光电子能谱(XPS)结果表明，PAN纳米纤维表面存在聚吡咯(PPy)层。用扫描电子显微镜和透射电子显微镜研究了核壳PAN/PPy纳米纤维的形态和结构，从扫描电子显微镜和透射电子显微镜的图像可以清楚地证明核壳结构的存在。吸附结果表明，随着初始溶液pH的降低，吸附容量增大。当初始溶液浓度从100 mg/L增加到200 mg/100时，30min和90min内达到吸附平衡，吸附过程符合准二级模型。等温线数据符合Langmuir等温线模型。热力学研究表明，吸附过程本质上是吸热自发的。解吸结果表明，使用5次后，吸附容量仍能保持在80%以上。并用XPS研究了其吸附机理。
Polyacrylonitrile/polypyrrole (PAN/PPy) core–shell structure nanofibers were prepared via electrospinning followed by in situ polymerization of pyrrole monomer for the removal of hexavalent chromium (Cr(VI)) from aqueous solution. Attenuated total reflections Fourier transform infrared (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS) results confirmed the presence of the polypyrrole (PPy) layer on the surface of PAN nanofibers. The morphology and structure of the core–shell PAN/PPy nanofibers were studied by scanning electron microscopy (SEM) and transmission electron microscope (TEM), and the core–shell structure can be clearly proved from the SEM and TEM images. Adsorption results indicated that the adsorption capacity increased with the initial solution pH decreased. The adsorption equilibrium reached within 30 and 90min as the initial solution concentration increased from 100 to 200mg/L, and the process can be described using the pseudo-second-order model. Isotherm data fitted well to the Langmuir isotherm model. Thermodynamic study revealed that the adsorption process is endothermic and spontaneous in nature. Desorption results showed that the adsorption capacity can remain up to 80% after 5 times usage. The adsorption mechanism was also studied by XPS.