High flux MWCNTs-interlinked GO hybrid membranes survived in cross-flow filtration for the treatment of strontium-containing wastewater

Lin Zhang; Ying Lu; Ying-Ling Liu; Ming Li; Hai-Yang Zhao; Li-An Hou

doi:10.1016/j.jhazmat.2016.08.020

High flux MWCNTs-interlinked GO hybrid membranes survived in cross-flow filtration for the treatment of strontium-containing wastewater

J Hazard Mater. 2016 Dec 15:320:187-193. doi: 10.1016/j.jhazmat.2016.08.020. Epub 2016 Aug 8.

Authors

Lin Zhang¹, Ying Lu¹, Ying-Ling Liu², Ming Li³, Hai-Yang Zhao¹, Li-An Hou⁴

Affiliations

¹ Key Laboratory of Biomass Chemical Engineering, Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, PR China.
² Department of Chemical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan.
³ Xi'an High-Tech Institute, Xi'an 710025, PR China.
⁴ Key Laboratory of Biomass Chemical Engineering, Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, PR China; Xi'an High-Tech Institute, Xi'an 710025, PR China. Electronic address: houla@cae.cn.

PMID: 27544731
DOI: 10.1016/j.jhazmat.2016.08.020

Abstract

Graphene oxide (GO)-based membranes provide an encouraging opportunity to support high separation efficiency for wastewater treatment. However, due to the relatively weak interaction between GO nanosheets, it is difficult for bare GO-based membranes to survive in cross-flow filtration. In addition, the permeation flux of the bare GO membrane is not high sufficiently due to its narrow interlayer spacing. In this study, GO membranes interlinked with multi-walled carbon nanotubes (MWCNTs) via covalent bonds were fabricated on modified polyacrylonitrile (PAN) supports by vacuum filtration. Due to the strong bonds between GO, MWCNTs and the PAN membrane, the membranes could be used for the treatment of simulated nuclear wastewater containing strontium via a cross-flow process. The result showed a high flux of 210.7L/(m²h) at 0.4MPa, which was approximately 4 times higher than that of commercial nanofiltration membranes. The improved water permeation was attributed to the nanochannels created by the interlinked MWCNTs in the GO layers. In addition, the hybrid membrane exhibited a high rejection of 93.4% for EDTA-chelated Sr²⁺ in an alkaline solution, and could also be used to separate Na⁺/Sr²⁺ mixtures. These results indicate that the MWCNTs-interlinked GO membrane has promising prospects for application in radioactive waste treatment.

Keywords: Cross-flow process; Graphene oxide; High flux; MWCNTs; Radioactive water.