Nanofiltration Membrane via Organic Nanoparticle-Assisted Interface Polymerization for Efficient Dye/Salt Separation

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Nanofiltration membranes are crucial for water purification but suffer from low flux and unclear wrinkling mechanisms.
• Interface polymer membranes face challenges with low water permeance, hindering their practical application.
• Understanding nanofiller-induced wrinkling is key to improving membrane performance.

Purpose of the Study:

• To synthesize superhydrophilic nanoparticles for interface polymerization.
• To investigate the effect of these nanoparticles on membrane surface morphology and properties.
• To enhance the performance of nanofiltration membranes for efficient water treatment.

Main Methods:

• Synthesis of l-histidine-modified nanoparticles.
• Incorporation of nanoparticles into the interface polymerization process.
• Characterization of membrane surface morphology, hydrophilicity, and separation performance.

Main Results:

• Nanoparticle addition induced layered wrinkles, increasing surface area and hydrophilicity (water contact angle reduced from 51.85° to 28.72°).
• A nanofiltration membrane with 0.1 wt% modified dopamine particles achieved 145.57 L m⁻² h⁻¹ MPa⁻¹ water permeance.
• Over 99% dye rejection and high inorganic salt ion permeability were observed, demonstrating efficient dye/salt separation.

Conclusions:

• Superhydrophilic nanoparticles effectively induce interface polymerization and surface wrinkling in membranes.
• The modified membranes exhibit significantly enhanced hydrophilicity, water flux, and separation performance.
• This approach offers a promising strategy for developing stable and highly applicable nanofiltration membranes for water resource challenges.