Deakin University
Browse

File(s) under permanent embargo

Hierarchically Active Poly(vinylidene fluoride) Membrane Fabricated by in Situ Generated Zero-Valent Iron for Fouling Reduction

journal contribution
posted on 2020-01-01, 00:00 authored by Z He, S Mahmud, Shuaifei ZhaoShuaifei Zhao, Y Yang, L Zhu, Y Zhao, Q Zeng, Z Xiong, C Hu
© 2020 American Chemical Society. Sodium hypochlorite (NaClO) solution is a typical cleaning agent for membrane fouling. However, it can damage membrane chemical structures and produce toxic disinfection byproducts, which in turn reduces the membrane performance. This study focuses on the fabrication of active membranes thereby overcoming the limitations of chemical cleaning. A hierarchical active poly(vinylidene fluoride) membrane with polydopamine/polyethyleneimine (PEI) co-supported iron nanoparticle (Fe NP) catalysts was successfully constructed and denoted as a Fe-HP-membrane. The Fe-HP-membrane exhibited excellent advanced oxidation activity with maximum flux recoveries (∼85% with bovine serum albumin [BSA] and ∼95% with humic acid [HA] solutions). After the static experiment of ∼30 days, the BSA proteins and HA successfully desorbed from the membrane surface. Especially, with a trace amount of hydrogen peroxide (H2O2) flowing over the surface of the Fe-HP-membrane, highly exposed active sites were observed. Membrane cleaning showed that the "outside-to-in" active surfaces generated considerable amounts of •OH radicals at the interface of BSA or HA and the fouled membrane. As a result, the unwanted foulants were successfully removed from the membrane interface, enabling multiple use of the Fe-HP-membrane. Therefore, backwashing with a small amount of H2O2 (0.33 wt %) covered ∼20% of the flux. In contrary, backwashing with NaClO (1 wt %) can only achieve a flux recovery of ∼10% after six consecutive BSA filtration cycles. The Fe-HP-membrane exhibited better HA foulant removal (a flux recovery of ∼51%) after backwashing with H2O2 than using NaClO (a flux recovery of ∼43%). Our findings demonstrate a new platform for water treatment and regeneration of fouled membranes.

History

Journal

ACS Applied Materials and Interfaces

Volume

12

Pagination

10993-11004

Location

Washington, D.C.

ISSN

1944-8244

eISSN

1944-8252

Language

eng

Publication classification

C1 Refereed article in a scholarly journal

Issue

9

Publisher

ACS Publications