Advanced Functionalized Electrospun Membrane for Water Treatment: Comparing Low Frequency Ultrasound Effects on ENMs and PES Membranes in CNC Filtration
(2025) METM01 20251Chemical Engineering (M.Sc.Eng.)
- Abstract
- This thesis investigates how low-frequency ultrasound can enhance membrane filtration performance and reduce fouling, one of the most critical limitations of membranes in water treatment technologies. Two types of membranes were studied. Flat-sheet polyethersulfone (PES) membranes, widely used for their mechanical and chemical stability, and electrospun nanofiber membranes (ENMs) made from styrene-butadiene rubber (SBR), which offer high porosity and permeability. Experiments were conducted in both dead-end and crossflow filtration setups using cellulose nanocrystals (CNCs) as a model foulant. While PES membranes provided stable performance under various conditions, ENMs showed higher initial flux but were more sensitive to fouling and... (More)
- This thesis investigates how low-frequency ultrasound can enhance membrane filtration performance and reduce fouling, one of the most critical limitations of membranes in water treatment technologies. Two types of membranes were studied. Flat-sheet polyethersulfone (PES) membranes, widely used for their mechanical and chemical stability, and electrospun nanofiber membranes (ENMs) made from styrene-butadiene rubber (SBR), which offer high porosity and permeability. Experiments were conducted in both dead-end and crossflow filtration setups using cellulose nanocrystals (CNCs) as a model foulant. While PES membranes provided stable performance under various conditions, ENMs showed higher initial flux but were more sensitive to fouling and structural degradation, especially in unsupported or thin configurations. Applying ultrasound improved filtration performance in both systems by increasing water flux and partially mitigating fouling, particularly during active ultrasound phases. Notably, this study is among the first to systematically explore the direct application of ultrasound to electrospun membranes during active filtration, an area that had previously remained largely unexamined, despite its promising potential for enhancing membrane performance. To understand the structural dynamics behind fouling, Small-Angle X-ray Scattering (SAXS) was used to analyze how CNCs build up on the membrane over time. This analysis revealed concentration gradients and particle accumulation near the membrane surface, offering valuable insight into the stages of fouling. (Less)
- Popular Abstract
- Water is something most of us take for granted, turn on the tap, and there it is. But for many people around the world, clean water is becoming harder to find. Pollution, climate change, and industrial waste are making it more difficult to treat and reuse water safely. As these problems grow, scientists are working on more sustainable ways to clean water.
One of the most promising tools for water purification is a membrane, a thin filter that lets clean water through while blocking dirt, bacteria, and other unwanted particles. However, over time, even the best membranes can get clogged up, this problem is known as fouling, and it’s one of the biggest challenges in water treatment today.
This research looked at a way to reduce this... (More) - Water is something most of us take for granted, turn on the tap, and there it is. But for many people around the world, clean water is becoming harder to find. Pollution, climate change, and industrial waste are making it more difficult to treat and reuse water safely. As these problems grow, scientists are working on more sustainable ways to clean water.
One of the most promising tools for water purification is a membrane, a thin filter that lets clean water through while blocking dirt, bacteria, and other unwanted particles. However, over time, even the best membranes can get clogged up, this problem is known as fouling, and it’s one of the biggest challenges in water treatment today.
This research looked at a way to reduce this fouling: by using sound waves. Not the kind we hear with our ears, but high-frequency vibrations known as ultrasound. These sound waves can shake and loose the particles stuck on the membrane’s surface, helping to keep it clean and working better for longer times.
Two types of membranes were tested in this project for the filtration of the cellulose nanocrystal (CNC) suspensions under ultrasound. One was a commercial polyethersulfone (PES) membrane, commonly used in water treatment applications. The other was made from electrospun nanofibers, fabricated at Politecnico di Torino University in Italy.
The Filtration tests showed that applying ultrasound during operation significantly reduced fouling and improved water flow. In some cases, membranes maintained nearly 100% of their initial water flux, meaning they stayed efficient over time. The electrospun nanofibers membranes (ENMs) responded particularly well to ultrasound, remaining intact without visible damage. However, their flux behavior varied, likely due to differences in their structure and non-uniformity in the way they were manufactured.
To better understand how CNC particles accumulated on the membrane during filtration, a technique called Small-Angle X-ray Scattering (SAXS) was used. This advanced method can be used to see how particles were distributed layer by layer on the membrane surface and how fouling develops over time and provided deeper insight into how ultrasound helps reduce it.
Another unique aspect of this research was that, unlike traditional membranes, electrospun membranes had never been tested with ultrasound during filtration. By comparing these ENMs to the PES membranes under the same conditions, with and without ultrasound, clear differences in how they responded can be analyzed. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9211384
- author
- Sabbaghian, Golshan LU
- supervisor
- organization
- course
- METM01 20251
- year
- 2025
- type
- H2 - Master's Degree (Two Years)
- subject
- keywords
- Membrane Engineering, Electrospun Membranes, Ultrasound-assisted Filtration, Membrane Fouling, Polyethersulfone Membranes, SAXS, Nanofiber structure, Water Treatment
- language
- English
- id
- 9211384
- date added to LUP
- 2025-09-02 13:58:12
- date last changed
- 2025-09-02 13:58:12
@misc{9211384,
abstract = {{This thesis investigates how low-frequency ultrasound can enhance membrane filtration performance and reduce fouling, one of the most critical limitations of membranes in water treatment technologies. Two types of membranes were studied. Flat-sheet polyethersulfone (PES) membranes, widely used for their mechanical and chemical stability, and electrospun nanofiber membranes (ENMs) made from styrene-butadiene rubber (SBR), which offer high porosity and permeability. Experiments were conducted in both dead-end and crossflow filtration setups using cellulose nanocrystals (CNCs) as a model foulant. While PES membranes provided stable performance under various conditions, ENMs showed higher initial flux but were more sensitive to fouling and structural degradation, especially in unsupported or thin configurations. Applying ultrasound improved filtration performance in both systems by increasing water flux and partially mitigating fouling, particularly during active ultrasound phases. Notably, this study is among the first to systematically explore the direct application of ultrasound to electrospun membranes during active filtration, an area that had previously remained largely unexamined, despite its promising potential for enhancing membrane performance. To understand the structural dynamics behind fouling, Small-Angle X-ray Scattering (SAXS) was used to analyze how CNCs build up on the membrane over time. This analysis revealed concentration gradients and particle accumulation near the membrane surface, offering valuable insight into the stages of fouling.}},
author = {{Sabbaghian, Golshan}},
language = {{eng}},
note = {{Student Paper}},
title = {{Advanced Functionalized Electrospun Membrane for Water Treatment: Comparing Low Frequency Ultrasound Effects on ENMs and PES Membranes in CNC Filtration}},
year = {{2025}},
}