A review on nanofiltration membrane fabrication and modification using polyelectrolytes: effective ways to develop...

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Nanofiltration (NF) performance relies on sieving and Donnan effects, influenced by membrane surface charges.
• Polyelectrolytes are utilized to enhance NF membrane properties due to their pore-sealing and charge-modifying capabilities.
• Optimizing pH, electrolyte, and polyelectrolyte characteristics improves electrostatic interactions for membrane modification.

Purpose of the Study:

• To explore the use of polyelectrolyte modification for improving nanofiltration membrane performance.
• To investigate how polyelectrolytes enhance membrane surface charge density, coating stability, and selectivity.
• To review various methods for incorporating polyelectrolytes and suitable evaluation instruments.

Main Methods:

• Incorporation of polyelectrolytes via static deposition, dynamic deposition, single layer coating, and layer-by-layer (LbL) coating.
• Manipulation of solution parameters (pH, electrolyte concentration, polyelectrolyte type/concentration) to tailor membrane properties.
• Evaluation of polyelectrolyte-modified membranes using recommended devices and instruments.

Main Results:

• Polyelectrolyte modification significantly improves NF membrane surface charge density and selectivity.
• Enhanced electrostatic interactions lead to improved membrane surface coating stability.
• Various deposition techniques effectively incorporate polyelectrolytes to boost membrane performance.

Conclusions:

• Polyelectrolyte-modified membranes offer substantial performance improvements for nanofiltration.
• Fabrication is rapid, requiring less energy and resulting in lower production costs.
• Further research into factors influencing these membranes is warranted for future advancements.