PubAg

Main content area

Selective removal of tungstate anions from aqueous solutions by surface anion‐imprinted ceramic membranes

Author:
Dong, Zhihui, Zeng, Jianxian, Zhou, Hu, Lv, Chaoqiang, Ma, Yichang, Zeng, Jiehui
Source:
Journal of chemical technology and biotechnology 2019 v.94 no.3 pp. 942-954
ISSN:
0268-2575
Subject:
Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, anions, aqueous solutions, binding capacity, ceramics, chromium, electrostatic interactions, filtration, molybdenum, pH, porosity, scanning electron microscopy, technology, thermogravimetry
Abstract:
BACKGROUND: It is significantly important to develop new technologies and materials for removal of tungstate anions (W(VI)) from aqueous solutions. An ion imprinted membrane not only possesses all virtues of a separation membrane, but also has tailor‐made recognition sites. In this work, a novel surface anion‐imprinted ceramic membrane (IIP‐PEI/CM) was fabricated to remove W(VI) selectively from aqueous solutions. RESULTS: FT‐IR, XPS, TGA, SEM, streaming potential, pore size distribution and water flux confirmed the successful fabrication of IIP‐PEI/CM. With increasing pH, binding capacities (Qₑ) of W(VI) onto IIP‐PEI/CM and non‐imprinted membrane (NIP‐PEI/CM) rapidly decreased. At pH = 2.0, Qₑ values of IIP‐PEI/CM and NIP‐PEI/CM were 139.4 and 47.9 mg 100 g⁻¹, respectively. Binding equilibrium was achieved within 3 min, showing an ultra‐fast kinetic process. Compared with NIP‐PEI/CM, IIP‐PEI/CM had higher selectivity for W(VI) in the presence of Mo(VI) and Cr(VI) ions, and its selectivity coefficients for W(VI)/Mo(VI) and W(VI)/Cr(VI) were 15.47 and 19.74, respectively. During dynamic filtration, IIP‐PEI/CM was effective and selective for removal of W(VI), and it had a good reusability. Protonated amine groups within PEI participated the uptake of W(VI) by electrostatic interactions. CONCLUSION: IIP‐PEI/CM showed ultrafast and selective binding of W(VI) anions, and has potential application for W(VI) removal/recovery from aqueous solutions. © 2018 Society of Chemical Industry
Agid:
6304694