Improved PVDF membrane performance by doping extracellular polymeric substances of activated sludge

Area of Science:

• Materials Science
• Environmental Engineering
• Chemical Engineering

Background:

• Polyvinylidene fluoride (PVDF) membranes are vital for water treatment due to their durability.
• The inherent hydrophobicity of PVDF membranes leads to fouling, reducing efficiency.
• Improving the anti-fouling properties of PVDF membranes is crucial for sustainable water purification.

Purpose of the Study:

• To enhance the anti-fouling capabilities of PVDF membranes using extracellular polymeric substances (EPS).
• To investigate the effects of EPS blending on PVDF membrane structure and performance.
• To develop a cost-effective method for improving membrane-based water and wastewater treatment.

Main Methods:

• In-situ blending of extracellular polymeric substances (EPS) from activated sludge into PVDF.
• Fabrication of modified PVDF membranes via phase inversion.
• Characterization of membrane morphology, hydrophilicity, and pore size distribution.
• Surface thermodynamic calculations to assess membrane properties.

Main Results:

• Blending 8% EPS significantly improved pure water flux and anti-fouling performance.
• EPS introduction increased membrane hydrophilicity and altered cross-section morphology, forming large cavities.
• An increase in pore size fraction (100-500 nm) was observed, benefiting membrane performance.
• EPS-functionalized membranes exhibited higher cohesion free energy, indicating better pollutant rejection.

Conclusions:

• EPS blending offers a simple, efficient, and cost-effective strategy to enhance PVDF membrane performance.
• The modified membranes show improved hydrophilicity and pore structure, leading to superior anti-fouling properties.
• This approach extends the application of EPS in advanced membrane technology for water treatment.