Mitigation of bidirectional solute flux in forward osmosis via membrane surface coating of zwitterion functionalized carbon nanotubes

Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved..

Forward osmosis (FO) has emerged as a promising membrane technology to yield high-quality reusable water from various water sources. A key challenge to be solved is the bidirectional solute flux (BSF), including reverse solute flux (RSF) and forward solute flux (FSF). Herein, zwitterion functionalized carbon nanotubes (Z-CNTs) have been coated onto a commercial thin film composite (TFC) membrane, resulting in BSF mitigation via both electrostatic repulsion forces induced by zwitterionic functional groups and steric interactions with CNTs. At a coating density of 0.97 g m-2, a significantly reduced specific RSF was observed for multiple draw solutes, including NaCl (55.5% reduction), NH4H2PO4 (83.8%), (NH4)2HPO4 (74.5%), NH4Cl (70.8%), and NH4HCO3 (61.9%). When a synthetic wastewater was applied as the feed to investigate membrane rejection, FSF was notably reduced by using the coated membrane with fewer pollutants leaked to the draw solution, including NH4+-N (46.3% reduction), NO2--N (37.0%), NO3--N (30.3%), K+ (56.1%), PO43--P (100%), and Mg2+ (100%). When fed with real wastewater, a consistent water flux was achieved during semi-continuous operation with enhanced fouling resistance. This study is among the earliest efforts to address BSF control via membrane modification, and the results will encourage further exploration of effective strategies to reduce BSF.

Medienart:

E-Artikel

Erscheinungsjahr:

2019

Erschienen:

2019

Enthalten in:

Zur Gesamtaufnahme - volume:131

Enthalten in:

Environment international - 131(2019) vom: 30. Okt., Seite 104970

Sprache:

Englisch

Beteiligte Personen:

Zou, Shiqiang [VerfasserIn]
Smith, Ethan D [VerfasserIn]
Lin, Shihong [VerfasserIn]
Martin, Stephen M [VerfasserIn]
He, Zhen [VerfasserIn]

Links:

Volltext

Themen:

059QF0KO0R
Forward osmosis
Forward solute flux
Journal Article
Membrane modification
Membranes, Artificial
Nanotubes, Carbon
Research Support, Non-U.S. Gov't
Reverse solute flux
Waste Water
Water
Zwitterion

Anmerkungen:

Date Completed 20.02.2020

Date Revised 07.12.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.envint.2019.104970

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM299087794