Jump to main content
Jump to site search

Issue 26, 2017
Previous Article Next Article

Zwitterionic carbon nanotube assisted thin-film nanocomposite membranes with excellent efficiency for separation of mono/divalent ions from brackish water

Author affiliations

Abstract

Zwitterionization of multiwalled carbon nanotubes (ZCNTs) is initially conducted by grafting poly(4-styrenesulfonic acid) and poly(4-vinylpyridine) copolymers via an atom transfer radical polymerization (ATRP) reaction, and the products obtained are further used as an aqueous additive to fabricate thin-film nanocomposite (TFN) nanofiltration (NF) membranes. The most optimal membrane with a ZCNT dosage of 0.01%, Z-TFN 0.01% shows nearly 31% enhancement in water permeability (14.9 ± 0.5 L m−2 h−1 bar−1), probably due to the shortened ZCNT, which could create a larger number of inorganic–organic interfaces in the barrier layers. Besides, it also exhibits MgSO4/NaCl selectivity (5.6 ± 0.8), 2.8 times higher than that of the pristine one (2.0 ± 0.2), which is attributed to the formation of ion-response channels and the stretching effect of the side chains. By using model brackish water as the feed solution and subjecting it to a two-stage NF process, the outstanding separation ability of the Z-TFN 0.01% membrane for the ions with the final Na+/Mg2+ concentration ratio in the permeate reaching as high as 589.2, as against only 111.7 for the control, is displayed. Furthermore, due to the strong bacteriostasis ability of quaternary ammonium compounds, Z-TFN 0.01% also shows excellent antibacterial properties, as evidenced by the mortality of Escherichia coli to 97% after remaining in contact with the membrane surface.

Graphical abstract: Zwitterionic carbon nanotube assisted thin-film nanocomposite membranes with excellent efficiency for separation of mono/divalent ions from brackish water

Back to tab navigation

Supplementary files

Publication details

The article was received on 01 Apr 2017, accepted on 24 May 2017 and first published on 24 May 2017


Article type: Paper
DOI: 10.1039/C7TA02837G
Citation: J. Mater. Chem. A, 2017,5, 13730-13739
  •   Request permissions

    Zwitterionic carbon nanotube assisted thin-film nanocomposite membranes with excellent efficiency for separation of mono/divalent ions from brackish water

    J. Zheng, M. Li, Y. Yao, X. Zhang and L. Wang, J. Mater. Chem. A, 2017, 5, 13730
    DOI: 10.1039/C7TA02837G

Search articles by author

Spotlight

Advertisements