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Frontiers of Environmental Science & Engineering

Front. Environ. Sci. Eng.    2019, Vol. 13 Issue (6) : 81     https://doi.org/10.1007/s11783-019-1165-9
RESEARCH ARTICLE
G-CNTs/PVDF mixed matrix membranes with improved antifouling properties and filtration performance
Xiaoyan Guo1,2, Chunyu Li1,2, Chenghao Li1,2, Tingting Wei1, Lin Tong1,2, Huaiqi Shao3, Qixing Zhou1, Lan Wang1, Yuan Liao2()
1. Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
2. Sino-Canada Joint R&D Centre for Water and Environmental Safety, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
3. College of Chemical Engineering and Materials Science, Tianjin University of Science & Technology, Tianjin 300457, China
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Abstract

A novel nanocomposite OMWCNT-A-GO was synthesized by conjugating OMWCNT and GO.

The P-OMWCNT-A-GO membrane was fabricated by non-solvent induced phase inversion.

The P-OMWCNT-A-GO exhibits the best water flux, BSA rejection and flux recovery.

It should be due to the enhanced membrane pore size, porosity and hydrophilicity.

Although carbon nanomaterials have been widely used as effective nanofillers for fabrication of mixed matrix membranes (MMMs) with outstanding performances, the reproducibility of the fabricated MMMs is still hindered by the non-homogenous dispersion of these carbon nanofillers in membrane substrate. Herein, we report an effective way to improve the compatibility of carbon-based nanomaterials with membrane matrixes. By chemically conjugating the oxidized CNTs (o-CNTs) and GO using hexanediamine as cross-linker, a novel carbon nanohybrid material (G-CNTs) was synthesized, which inherited both the advanced properties of multi-walled carbon nanotubes (CNTs) and graphene oxide (GO). The G-CNTs incorporated polyvinylidene fluoride (PVDF) MMMs (G-CNTs/PVDF) were fabricated via a non-solvent induced phase separation (NIPS) method. The filtration and antifouling performances of G-CNTs/PVDF were evaluated using distillate water and a 1 g/L bovine serum albumin (BSA) aqueous solution under 0.10 MPa. Compared to the MMMs prepared with o-CNTs, GO, the physical mixture of o-CNTs and GO and pure PVDF membrane, the G-CNTs/PVDF membrane exhibited the highest water flux up to 220 L/m2/h and a flux recovery ratio as high as 90%, as well as the best BSA rejection rate. The excellent performances should be attributed to the increased membrane pore size, porosity and hydrophilicity of the resulted membrane. The successful synthesis of the novel nanohybrid G-CNTs provides a new type of nanofillers for MMMs fabrication.

Keywords carbon nanotubes      graphene oxide      mixed matrix membrane      nanohybrid      antifouling membrane      membrane hydrophilicity     
This article is part of themed collection: China Urban Water Environment and Water Ecology (Responsible Editors: Shubo Deng & Huijuan Liu)
Corresponding Author(s): Yuan Liao   
Issue Date: 27 August 2019
 Cite this article:   
Xiaoyan Guo,Chunyu Li,Chenghao Li, et al. G-CNTs/PVDF mixed matrix membranes with improved antifouling properties and filtration performance[J]. Front. Environ. Sci. Eng., 2019, 13(6): 81.
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http://journal.hep.com.cn/fese/EN/10.1007/s11783-019-1165-9
http://journal.hep.com.cn/fese/EN/Y2019/V13/I6/81
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Xiaoyan Guo
Chunyu Li
Chenghao Li
Tingting Wei
Lin Tong
Huaiqi Shao
Qixing Zhou
Lan Wang
Yuan Liao
Fig.1  Schematic of the laboratory-scale dead-end filtration system (Millipore 8200).
Fig.2  The chemical reactions involved for preparation of carbon nanohybrid material (G-CNTs).
Fig.3  FTIR spectra of (a) o-CNTs; (b) GO; (c) G-CNTs.
Fig.4  XPS survey spectrum of G-CNTs nanohybrids.
Fig.5  TEM images of the G-CNTs nanohybrids.
Fig.6  SEM images of the top surfaces of membranes (a) plain PVDF; (b) P-o-CNTs; (c) P-GO; (d) P-GO-CNTs; (e) P-G-CNTs.
Fig.7  Pore size and porosity of the various membranes.
Fig.8  Contact angles of different MMMs prepared without any filler (pure PVDF) and with o-CNTs, GO, GO-CNTs, G-CNTs.
Fig.9  Pure water fluxes and rejections to BSA at an operating pressure of 0.1 MPa for various MMMs.
Fig.10  Anti-fouling performance of various membranes evaluated with BSA solution at an operating pressure of 0.1 MPa.
Fig.11  Flux recovery ratio (FRR), reversible fouling ratio (Rr) and irreversible fouling ratio (Rir) of the MMMs developed in this work.
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