Cargando…

Quantifying Concentration Polarization – Raman Microspectroscopy for In-Situ Measurement in a Flat Sheet Cross-flow Nanofiltration Membrane Unit

In this work, the concentration polarization layer (CPL) of sulphate in a cross-flow membrane system was measured in-situ using Raman microspectroscopy (RM). The focus of this work is to introduce RM as a new tool for the study of mass transfer inside membrane channels in reverse osmosis (RO) and na...

Descripción completa

Detalles Bibliográficos
Autores principales: Jung, Oliver, Saravia, Florencia, Wagner, Michael, Heißler, Stefan, Horn, Harald
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group UK 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6828971/
https://www.ncbi.nlm.nih.gov/pubmed/31685941
http://dx.doi.org/10.1038/s41598-019-52369-1
_version_ 1783465460389380096
author Jung, Oliver
Saravia, Florencia
Wagner, Michael
Heißler, Stefan
Horn, Harald
author_facet Jung, Oliver
Saravia, Florencia
Wagner, Michael
Heißler, Stefan
Horn, Harald
author_sort Jung, Oliver
collection PubMed
description In this work, the concentration polarization layer (CPL) of sulphate in a cross-flow membrane system was measured in-situ using Raman microspectroscopy (RM). The focus of this work is to introduce RM as a new tool for the study of mass transfer inside membrane channels in reverse osmosis (RO) and nanofiltration (NF) generally. Specifically, this work demonstrates how to use RM for locally resolved measurement of sulphate concentration in a cross-flow flat-sheet NF membrane flow cell with channel dimensions similar to commonly applied RO/NF spiral wound modules (channel height about 0.7 mm). Concentration polarization profiles of an aqueous magnesium sulphate solution of 10 g(sulphate)·L(−1) were obtained at operating pressure of 10 bar and cross-flow velocities of 0.04 and 0.2 m·s(−1). The ability of RM to provide accurate concentration profiles is discussed thoroughly. Optical effects due to refraction present one of the main challenges of the method by substantially affecting signal intensity and depth resolution. The concentration profiles obtained in this concept study are consistent with theory and show reduced CPL thickness and membrane wall concentration with increasing cross-flow velocity. The severity of CP was quantified to reach almost double the bulk concentration at the lower velocity.
format Online
Article
Text
id pubmed-6828971
institution National Center for Biotechnology Information
language English
publishDate 2019
publisher Nature Publishing Group UK
record_format MEDLINE/PubMed
spelling pubmed-68289712019-11-12 Quantifying Concentration Polarization – Raman Microspectroscopy for In-Situ Measurement in a Flat Sheet Cross-flow Nanofiltration Membrane Unit Jung, Oliver Saravia, Florencia Wagner, Michael Heißler, Stefan Horn, Harald Sci Rep Article In this work, the concentration polarization layer (CPL) of sulphate in a cross-flow membrane system was measured in-situ using Raman microspectroscopy (RM). The focus of this work is to introduce RM as a new tool for the study of mass transfer inside membrane channels in reverse osmosis (RO) and nanofiltration (NF) generally. Specifically, this work demonstrates how to use RM for locally resolved measurement of sulphate concentration in a cross-flow flat-sheet NF membrane flow cell with channel dimensions similar to commonly applied RO/NF spiral wound modules (channel height about 0.7 mm). Concentration polarization profiles of an aqueous magnesium sulphate solution of 10 g(sulphate)·L(−1) were obtained at operating pressure of 10 bar and cross-flow velocities of 0.04 and 0.2 m·s(−1). The ability of RM to provide accurate concentration profiles is discussed thoroughly. Optical effects due to refraction present one of the main challenges of the method by substantially affecting signal intensity and depth resolution. The concentration profiles obtained in this concept study are consistent with theory and show reduced CPL thickness and membrane wall concentration with increasing cross-flow velocity. The severity of CP was quantified to reach almost double the bulk concentration at the lower velocity. Nature Publishing Group UK 2019-11-04 /pmc/articles/PMC6828971/ /pubmed/31685941 http://dx.doi.org/10.1038/s41598-019-52369-1 Text en © The Author(s) 2019 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
spellingShingle Article
Jung, Oliver
Saravia, Florencia
Wagner, Michael
Heißler, Stefan
Horn, Harald
Quantifying Concentration Polarization – Raman Microspectroscopy for In-Situ Measurement in a Flat Sheet Cross-flow Nanofiltration Membrane Unit
title Quantifying Concentration Polarization – Raman Microspectroscopy for In-Situ Measurement in a Flat Sheet Cross-flow Nanofiltration Membrane Unit
title_full Quantifying Concentration Polarization – Raman Microspectroscopy for In-Situ Measurement in a Flat Sheet Cross-flow Nanofiltration Membrane Unit
title_fullStr Quantifying Concentration Polarization – Raman Microspectroscopy for In-Situ Measurement in a Flat Sheet Cross-flow Nanofiltration Membrane Unit
title_full_unstemmed Quantifying Concentration Polarization – Raman Microspectroscopy for In-Situ Measurement in a Flat Sheet Cross-flow Nanofiltration Membrane Unit
title_short Quantifying Concentration Polarization – Raman Microspectroscopy for In-Situ Measurement in a Flat Sheet Cross-flow Nanofiltration Membrane Unit
title_sort quantifying concentration polarization – raman microspectroscopy for in-situ measurement in a flat sheet cross-flow nanofiltration membrane unit
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6828971/
https://www.ncbi.nlm.nih.gov/pubmed/31685941
http://dx.doi.org/10.1038/s41598-019-52369-1
work_keys_str_mv AT jungoliver quantifyingconcentrationpolarizationramanmicrospectroscopyforinsitumeasurementinaflatsheetcrossflownanofiltrationmembraneunit
AT saraviaflorencia quantifyingconcentrationpolarizationramanmicrospectroscopyforinsitumeasurementinaflatsheetcrossflownanofiltrationmembraneunit
AT wagnermichael quantifyingconcentrationpolarizationramanmicrospectroscopyforinsitumeasurementinaflatsheetcrossflownanofiltrationmembraneunit
AT heißlerstefan quantifyingconcentrationpolarizationramanmicrospectroscopyforinsitumeasurementinaflatsheetcrossflownanofiltrationmembraneunit
AT hornharald quantifyingconcentrationpolarizationramanmicrospectroscopyforinsitumeasurementinaflatsheetcrossflownanofiltrationmembraneunit