TY - JOUR
T1 - Vacuum-assisted MPD loading toward promoted nanoscale structure and enhanced water permeance of polyamide RO membrane
AU - Wu, Siqi
AU - Wang, Fei
AU - Zhou, Shenghua
AU - Long, Li
AU - Yang, Zhe
AU - Tang, Chuyang Y.
N1 - Funding Information:
This work was financially supported by the Senior Research Fellow Scheme of Research Grants Council (Project # SRFS2021-7S04). We also acknowledge the partial support by the Seed Grant for Basic Research (104006094) of the University of Hong Kong.
Publisher Copyright:
© 2022 Elsevier B.V.
PY - 2022/9/15
Y1 - 2022/9/15
N2 - Thin-film composite (TFC) reverse osmosis (RO) membranes fabricated by interfacial polymerization (IP) have been widely applied in seawater desalination. Nevertheless, their separation performance is limited by the permeance-selectivity upper bound. Compared to conventional synthesis/modification techniques, the manipulation of amine monomer distribution for the IP reaction has been far less investigated. In this study, we systematically investigated three classical approaches for m-phenylenediamine (MPD) loading during the IP reaction, i.e., vacuum filtration (TFC-V), roller (TFC-R), and air gun (TFC-A). Our results suggested that the vacuum-assisted approach can greatly enhance the availability of MPD monomers, which could, in turn, result in enhanced “ridge-and-valley” morphology of the polyamide rejection layer as a result of the enhanced nanofoaming effect. Furthermore, the TFC-V membrane demonstrated the highest water permeance of 2.8 ± 0.4 L m-2 h−1 bar−1 compared to TFC-R and TFC-A membranes of 2.1 ± 0.2 L m-2 h−1 bar−1 and 2.1 ± 0.4 L m-2 h−1 bar−1, respectively. This study provided mechanistic insights to facilitate an improved understanding of membrane synthesis–structure–performance relationships.
AB - Thin-film composite (TFC) reverse osmosis (RO) membranes fabricated by interfacial polymerization (IP) have been widely applied in seawater desalination. Nevertheless, their separation performance is limited by the permeance-selectivity upper bound. Compared to conventional synthesis/modification techniques, the manipulation of amine monomer distribution for the IP reaction has been far less investigated. In this study, we systematically investigated three classical approaches for m-phenylenediamine (MPD) loading during the IP reaction, i.e., vacuum filtration (TFC-V), roller (TFC-R), and air gun (TFC-A). Our results suggested that the vacuum-assisted approach can greatly enhance the availability of MPD monomers, which could, in turn, result in enhanced “ridge-and-valley” morphology of the polyamide rejection layer as a result of the enhanced nanofoaming effect. Furthermore, the TFC-V membrane demonstrated the highest water permeance of 2.8 ± 0.4 L m-2 h−1 bar−1 compared to TFC-R and TFC-A membranes of 2.1 ± 0.2 L m-2 h−1 bar−1 and 2.1 ± 0.4 L m-2 h−1 bar−1, respectively. This study provided mechanistic insights to facilitate an improved understanding of membrane synthesis–structure–performance relationships.
KW - Desalination
KW - Interfacial polymerization
KW - Reverse osmosis
KW - Thin-film composite membrane
KW - Vacuum-assisted interfacial polymerization
UR - http://www.scopus.com/inward/record.url?scp=85132758461&partnerID=8YFLogxK
U2 - 10.1016/j.seppur.2022.121547
DO - 10.1016/j.seppur.2022.121547
M3 - Journal article
AN - SCOPUS:85132758461
SN - 1383-5866
VL - 297
JO - Separation and Purification Technology
JF - Separation and Purification Technology
M1 - 121547
ER -