Membrane compaction, internal fouling, and membrane preconditioning as major factors affecting performance of solvent resistant nanofiltration membranes in methanol solutions

Sigyn Björk Sigurdardóttir, Mohd Shafiq Mohd Sueb, Manuel Pinelo*

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

The viability of using solvent-resistant nanofiltration (SRNF) membranes for concentration of a methanol solution containing a mixture of methyl lactate (ML), glycoaldehyde dimethyl acetal (GLAD), and methylvinylglycolate (MVG) was evaluated in this study. The highest retention was achieved with the GE AG membrane at 60 bars, compared to NF 270, Desal DK, and BW 30 membranes, where the retention was 20–30% lower at the same pressure. All membranes except NF 270 showed a high compaction effect at pressures above 40 bars, which explained the low flux and high retention at high pressures. Preconditioning the membranes with pure ethanol or methanol resulted in no differences in flux compared to the virgin membrane, which was in agreement with the “clustering effect” of the hydrophilic groups, which predicts same hydrophilicity but larger (and fewer) pores on the membrane surface. On the contrary, when the membranes were preconditioned with 50/50 alcohol mixtures of methanol or ethanol and water, a general decrease of flux and retention increase was observed, which was ascribed to the previously reported “pore wetting” effect exerted by water in alcohol mixtures. Increasing pH of the feed solution from 4 to 7 also caused decreases of flux and retention, which was explained by the increased internal fouling due to pore swelling. The results from this study suggest that the balance between compaction of the membrane due to high pressure and the pore size enlargement resulting from swelling and reorganization of the polymer chains of the membrane when subjected to organic solvents determines the size exclusion efficiency and susceptibility of the membrane to internal fouling, which in turn determine the performance of the membrane in terms of retention and flux.

Original languageEnglish
Article number115686
JournalSeparation and Purification Technology
Volume227
Number of pages8
ISSN1383-5866
DOIs
Publication statusPublished - 2019

Keywords

  • Internal fouling
  • Membrane compaction
  • Solution concentration
  • Solvent resistant nanofiltration membranes

Cite this

@article{65c80ef81a2b4ecdb75a6296c9eaf17a,
title = "Membrane compaction, internal fouling, and membrane preconditioning as major factors affecting performance of solvent resistant nanofiltration membranes in methanol solutions",
abstract = "The viability of using solvent-resistant nanofiltration (SRNF) membranes for concentration of a methanol solution containing a mixture of methyl lactate (ML), glycoaldehyde dimethyl acetal (GLAD), and methylvinylglycolate (MVG) was evaluated in this study. The highest retention was achieved with the GE AG membrane at 60 bars, compared to NF 270, Desal DK, and BW 30 membranes, where the retention was 20–30{\%} lower at the same pressure. All membranes except NF 270 showed a high compaction effect at pressures above 40 bars, which explained the low flux and high retention at high pressures. Preconditioning the membranes with pure ethanol or methanol resulted in no differences in flux compared to the virgin membrane, which was in agreement with the “clustering effect” of the hydrophilic groups, which predicts same hydrophilicity but larger (and fewer) pores on the membrane surface. On the contrary, when the membranes were preconditioned with 50/50 alcohol mixtures of methanol or ethanol and water, a general decrease of flux and retention increase was observed, which was ascribed to the previously reported “pore wetting” effect exerted by water in alcohol mixtures. Increasing pH of the feed solution from 4 to 7 also caused decreases of flux and retention, which was explained by the increased internal fouling due to pore swelling. The results from this study suggest that the balance between compaction of the membrane due to high pressure and the pore size enlargement resulting from swelling and reorganization of the polymer chains of the membrane when subjected to organic solvents determines the size exclusion efficiency and susceptibility of the membrane to internal fouling, which in turn determine the performance of the membrane in terms of retention and flux.",
keywords = "Internal fouling, Membrane compaction, Solution concentration, Solvent resistant nanofiltration membranes",
author = "Sigurdard{\'o}ttir, {Sigyn Bj{\"o}rk} and Sueb, {Mohd Shafiq Mohd} and Manuel Pinelo",
year = "2019",
doi = "10.1016/j.seppur.2019.115686",
language = "English",
volume = "227",
journal = "Separation and Purification Technology",
issn = "1383-5866",
publisher = "Pergamon Press",

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TY - JOUR

T1 - Membrane compaction, internal fouling, and membrane preconditioning as major factors affecting performance of solvent resistant nanofiltration membranes in methanol solutions

AU - Sigurdardóttir, Sigyn Björk

AU - Sueb, Mohd Shafiq Mohd

AU - Pinelo, Manuel

PY - 2019

Y1 - 2019

N2 - The viability of using solvent-resistant nanofiltration (SRNF) membranes for concentration of a methanol solution containing a mixture of methyl lactate (ML), glycoaldehyde dimethyl acetal (GLAD), and methylvinylglycolate (MVG) was evaluated in this study. The highest retention was achieved with the GE AG membrane at 60 bars, compared to NF 270, Desal DK, and BW 30 membranes, where the retention was 20–30% lower at the same pressure. All membranes except NF 270 showed a high compaction effect at pressures above 40 bars, which explained the low flux and high retention at high pressures. Preconditioning the membranes with pure ethanol or methanol resulted in no differences in flux compared to the virgin membrane, which was in agreement with the “clustering effect” of the hydrophilic groups, which predicts same hydrophilicity but larger (and fewer) pores on the membrane surface. On the contrary, when the membranes were preconditioned with 50/50 alcohol mixtures of methanol or ethanol and water, a general decrease of flux and retention increase was observed, which was ascribed to the previously reported “pore wetting” effect exerted by water in alcohol mixtures. Increasing pH of the feed solution from 4 to 7 also caused decreases of flux and retention, which was explained by the increased internal fouling due to pore swelling. The results from this study suggest that the balance between compaction of the membrane due to high pressure and the pore size enlargement resulting from swelling and reorganization of the polymer chains of the membrane when subjected to organic solvents determines the size exclusion efficiency and susceptibility of the membrane to internal fouling, which in turn determine the performance of the membrane in terms of retention and flux.

AB - The viability of using solvent-resistant nanofiltration (SRNF) membranes for concentration of a methanol solution containing a mixture of methyl lactate (ML), glycoaldehyde dimethyl acetal (GLAD), and methylvinylglycolate (MVG) was evaluated in this study. The highest retention was achieved with the GE AG membrane at 60 bars, compared to NF 270, Desal DK, and BW 30 membranes, where the retention was 20–30% lower at the same pressure. All membranes except NF 270 showed a high compaction effect at pressures above 40 bars, which explained the low flux and high retention at high pressures. Preconditioning the membranes with pure ethanol or methanol resulted in no differences in flux compared to the virgin membrane, which was in agreement with the “clustering effect” of the hydrophilic groups, which predicts same hydrophilicity but larger (and fewer) pores on the membrane surface. On the contrary, when the membranes were preconditioned with 50/50 alcohol mixtures of methanol or ethanol and water, a general decrease of flux and retention increase was observed, which was ascribed to the previously reported “pore wetting” effect exerted by water in alcohol mixtures. Increasing pH of the feed solution from 4 to 7 also caused decreases of flux and retention, which was explained by the increased internal fouling due to pore swelling. The results from this study suggest that the balance between compaction of the membrane due to high pressure and the pore size enlargement resulting from swelling and reorganization of the polymer chains of the membrane when subjected to organic solvents determines the size exclusion efficiency and susceptibility of the membrane to internal fouling, which in turn determine the performance of the membrane in terms of retention and flux.

KW - Internal fouling

KW - Membrane compaction

KW - Solution concentration

KW - Solvent resistant nanofiltration membranes

U2 - 10.1016/j.seppur.2019.115686

DO - 10.1016/j.seppur.2019.115686

M3 - Journal article

VL - 227

JO - Separation and Purification Technology

JF - Separation and Purification Technology

SN - 1383-5866

M1 - 115686

ER -