title: High-Flux Positively Charged Nanocomposite Nanofiltration Membranes Filled with Poly(dopamine) Modified Multiwall Carbon Nanotubes.
abstract: The poor dispensability of pristine carbon nanotubes in water impedes their implications in thin-film nanocomposite membranes for crucial utilities such as water purification. In this work, high-flux positively charged nanocomposite nanofiltration membranes were exploited by uniformly embedding poly(dopamine) modified multiwall carbon nanotubes (PDA-MWCNTs) in polyamide thin-film composite membranes. With poly(dopamine) modification, fine dispersion of MWCNTs in polyethyleneimine (PEI) aqueous solutions was achieved, which was interracially polymerized with trimesoyl chloride (TMC) n-hexane solutions to prepare nanocomposite membranes. The compatibility and interactions between modified MWCNTs and polyamide matrix were enhanced, attributed to the poly(dopamine) coatings on MWCNT surfaces, leading to significantly improved water permeability. At optimized conditions, pure water permeability of the PEI/PDA-MWCNTs/TMC nanofiltration membrane (M-4) was 15.32 L m(-2) h(-1) bar(-1), which was ∼1.6 times increased compared with that of pristine PEI/TMC membranes. Salt rejection of M-4 to different multivalent cations decreased in the sequence ZnCl2 (93.0%) > MgCl2 (91.5%) > CuCl2 (90.5%) ≈ CaCl2, which is well-suited for water softening and heavy metal ion removal.
authors.affiliation: MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science & Engineering, Zhejiang University , Hangzhou 310027, China .
authors.forename: Feng-Yang
authors.initials: FY
authors.lastname: Zhao
authors.affiliation: MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science & Engineering, Zhejiang University , Hangzhou 310027, China .
authors.forename: Yan-Li
authors.initials: YL
authors.lastname: Ji
authors.affiliation: College of Chemical Engineering and Bioengineering, Zhejiang University , Hangzhou 310027, China.
authors.forename: Xiao-Dan
authors.initials: XD
authors.lastname: Weng
authors.affiliation: MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science & Engineering, Zhejiang University , Hangzhou 310027, China .
authors.forename: Yi-Fang
authors.initials: YF
authors.lastname: Mi
authors.affiliation: MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science & Engineering, Zhejiang University , Hangzhou 310027, China .
authors.forename: Chun-Chun
authors.initials: CC
authors.lastname: Ye
authors.affiliation: MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science & Engineering, Zhejiang University , Hangzhou 310027, China .
authors.forename: Quan-Fu
authors.initials: QF
authors.lastname: An
authors.affiliation: College of Chemical Engineering and Bioengineering, Zhejiang University , Hangzhou 310027, China.|The Development Center of Water Treatment Technology , Hangzhou 310012, China.
authors.forename: Cong-Jie
authors.initials: CJ
authors.lastname: Gao
keywords: multiwall carbon nanotubes; nanocomposite; nanofiltration membrane; poly(dopamine); polyethyleneimine