Electrostatic control of membrane fouling in ultrafiltration treatment of protein-stabilized oil/water emulsions
Hameed, Ali Zain LU ; Kemperman, Antoine J.B. ; Lipnizki, Frank LU
and de Vos, Wiebe M.
(2026)
In Journal of Membrane Science
758.
- Abstract
Protein-stabilized oil–water emulsions are increasingly encountered in biorefinery and agro-industrial streams, yet their treatment by membrane filtration remains limited by insufficiently understood fouling mechanisms. Unlike synthetic surfactants, proteins exhibit intrinsic charge regulation and environment-dependent interfacial behavior that strongly influence droplet-droplet and droplet–membrane interactions. Here, we develop a physicochemical framework linking protein interfacial characteristics to ultrafiltration fouling behavior. By systematically varying emulsion feed conditions, specifically pH and ionic strength, we modulate protein interfacial properties and the interactions governing emulsion stability and membrane fouling.... (More)
Protein-stabilized oil–water emulsions are increasingly encountered in biorefinery and agro-industrial streams, yet their treatment by membrane filtration remains limited by insufficiently understood fouling mechanisms. Unlike synthetic surfactants, proteins exhibit intrinsic charge regulation and environment-dependent interfacial behavior that strongly influence droplet-droplet and droplet–membrane interactions. Here, we develop a physicochemical framework linking protein interfacial characteristics to ultrafiltration fouling behavior. By systematically varying emulsion feed conditions, specifically pH and ionic strength, we modulate protein interfacial properties and the interactions governing emulsion stability and membrane fouling. Using β-lactoglobulin, ovalbumin, and gelatin as model stabilizers, we show that pH governs protein charge state and membrane affinity, while ionic strength controls electrostatic screening and aggregation behavior. These measurements, together with DLVO interaction-energy calculations, define distinct interaction regimes in which pH-dependent charge modulation controls droplet stability and membrane affinity, whereas increasing salinity attenuates electrostatic repulsion, promotes aggregation, and shortens the effective interaction range. Building on this mechanistic foundation, we demonstrate that strongly repulsive pH conditions favor moderated flux decline and enhanced fouling reversibility, while charge neutralization or attraction near the isoelectric point promotes a more compact cake layer. In contrast, increasing ionic strength induces a transition from dispersion-stabilized deposition to aggregation-dominated fouling. By integrating interfacial characterization with filtration analysis, this work establishes electrostatic control of fouling as a practical design strategy for emerging bio-based separation processes.
(Less)
- author
- Hameed, Ali Zain
LU
; Kemperman, Antoine J.B.
; Lipnizki, Frank
LU
and de Vos, Wiebe M.
- organization
- publishing date
- 2026-10
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Biorefinery, Charge-induced rejection, Emulsion separation, Membrane fouling, Oil-water emulsions, Protein surfactant
- in
- Journal of Membrane Science
- volume
- 758
- article number
- 126079
- pages
- 16 pages
- publisher
- Elsevier
- external identifiers
-
- scopus:105048153759
- ISSN
- 0376-7388
- DOI
- 10.1016/j.memsci.2026.126079
- project
- Membranes as Enablers for Future Biorefineries: from Fabrication to Advanced Separation Technologies
- language
- English
- LU publication?
- yes
- additional info
- Publisher Copyright: © 2026 The Authors.
- id
- f3b9fe42-1791-4385-a67c-49000d9da9c9
- date added to LUP
- 2026-09-10 05:04:23
- date last changed
- 2026-09-14 14:15:19
@article{f3b9fe42-1791-4385-a67c-49000d9da9c9,
abstract = {{<p>Protein-stabilized oil–water emulsions are increasingly encountered in biorefinery and agro-industrial streams, yet their treatment by membrane filtration remains limited by insufficiently understood fouling mechanisms. Unlike synthetic surfactants, proteins exhibit intrinsic charge regulation and environment-dependent interfacial behavior that strongly influence droplet-droplet and droplet–membrane interactions. Here, we develop a physicochemical framework linking protein interfacial characteristics to ultrafiltration fouling behavior. By systematically varying emulsion feed conditions, specifically pH and ionic strength, we modulate protein interfacial properties and the interactions governing emulsion stability and membrane fouling. Using β-lactoglobulin, ovalbumin, and gelatin as model stabilizers, we show that pH governs protein charge state and membrane affinity, while ionic strength controls electrostatic screening and aggregation behavior. These measurements, together with DLVO interaction-energy calculations, define distinct interaction regimes in which pH-dependent charge modulation controls droplet stability and membrane affinity, whereas increasing salinity attenuates electrostatic repulsion, promotes aggregation, and shortens the effective interaction range. Building on this mechanistic foundation, we demonstrate that strongly repulsive pH conditions favor moderated flux decline and enhanced fouling reversibility, while charge neutralization or attraction near the isoelectric point promotes a more compact cake layer. In contrast, increasing ionic strength induces a transition from dispersion-stabilized deposition to aggregation-dominated fouling. By integrating interfacial characterization with filtration analysis, this work establishes electrostatic control of fouling as a practical design strategy for emerging bio-based separation processes.</p>}},
author = {{Hameed, Ali Zain and Kemperman, Antoine J.B. and Lipnizki, Frank and de Vos, Wiebe M.}},
issn = {{0376-7388}},
keywords = {{Biorefinery; Charge-induced rejection; Emulsion separation; Membrane fouling; Oil-water emulsions; Protein surfactant}},
language = {{eng}},
publisher = {{Elsevier}},
series = {{Journal of Membrane Science}},
title = {{Electrostatic control of membrane fouling in ultrafiltration treatment of protein-stabilized oil/water emulsions}},
url = {{http://dx.doi.org/10.1016/j.memsci.2026.126079}},
doi = {{10.1016/j.memsci.2026.126079}},
volume = {{758}},
year = {{2026}},
}