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Metastable State of Water and Performance of Osmotically Driven Membrane Processes

Semipermeable membranes play critical roles in many natural and engineering systems. The osmotic pressure is found experimentally much less effective than the hydraulic pressure to drive water through the membrane, which is commonly attributed to the internal concentration polarization (ICP) in the...

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Autores principales: Zhang, Haifeng, Wang, Jie, Rainwater, Ken, Song, Lianfa
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6468618/
https://www.ncbi.nlm.nih.gov/pubmed/30909379
http://dx.doi.org/10.3390/membranes9030043
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author Zhang, Haifeng
Wang, Jie
Rainwater, Ken
Song, Lianfa
author_facet Zhang, Haifeng
Wang, Jie
Rainwater, Ken
Song, Lianfa
author_sort Zhang, Haifeng
collection PubMed
description Semipermeable membranes play critical roles in many natural and engineering systems. The osmotic pressure is found experimentally much less effective than the hydraulic pressure to drive water through the membrane, which is commonly attributed to the internal concentration polarization (ICP) in the porous layer of the membrane. In this study, it has been shown that a necessary condition for the osmotic pressure to be effective is water continuity across the entire membrane thickness under negative pressure, i.e., the water inside the membrane remains in a metastable state. However, the metastable state of water cannot be maintained indefinitely, and cavitation will undoubtedly occur in the osmotically driven processes. Collapse of the water metastable state was suggested for the first time to be a more important and fundamental reason for the low water fluxes in the osmotically driven membrane processes.
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spelling pubmed-64686182019-04-22 Metastable State of Water and Performance of Osmotically Driven Membrane Processes Zhang, Haifeng Wang, Jie Rainwater, Ken Song, Lianfa Membranes (Basel) Communication Semipermeable membranes play critical roles in many natural and engineering systems. The osmotic pressure is found experimentally much less effective than the hydraulic pressure to drive water through the membrane, which is commonly attributed to the internal concentration polarization (ICP) in the porous layer of the membrane. In this study, it has been shown that a necessary condition for the osmotic pressure to be effective is water continuity across the entire membrane thickness under negative pressure, i.e., the water inside the membrane remains in a metastable state. However, the metastable state of water cannot be maintained indefinitely, and cavitation will undoubtedly occur in the osmotically driven processes. Collapse of the water metastable state was suggested for the first time to be a more important and fundamental reason for the low water fluxes in the osmotically driven membrane processes. MDPI 2019-03-22 /pmc/articles/PMC6468618/ /pubmed/30909379 http://dx.doi.org/10.3390/membranes9030043 Text en © 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Communication
Zhang, Haifeng
Wang, Jie
Rainwater, Ken
Song, Lianfa
Metastable State of Water and Performance of Osmotically Driven Membrane Processes
title Metastable State of Water and Performance of Osmotically Driven Membrane Processes
title_full Metastable State of Water and Performance of Osmotically Driven Membrane Processes
title_fullStr Metastable State of Water and Performance of Osmotically Driven Membrane Processes
title_full_unstemmed Metastable State of Water and Performance of Osmotically Driven Membrane Processes
title_short Metastable State of Water and Performance of Osmotically Driven Membrane Processes
title_sort metastable state of water and performance of osmotically driven membrane processes
topic Communication
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6468618/
https://www.ncbi.nlm.nih.gov/pubmed/30909379
http://dx.doi.org/10.3390/membranes9030043
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