γ-Valerolactone as Bio-Based Solvent for Nanofiltration Membrane Preparation.

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Membrane technology is crucial for water purification.
• Developing sustainable and efficient membrane materials is an ongoing challenge.
• Green solvents offer an environmentally friendly alternative for membrane fabrication.

Purpose of the Study:

• To explore gamma-valerolactone (GVL) as a green solvent for phase inversion membrane preparation.
• To screen sustainable non-solvents (water, ethanol) for nanofiltration (NF) membrane fabrication.
• To optimize NF membrane performance using cellulose triacetate (CTA) and other polymers.

Main Methods:

• Phase inversion process using GVL as solvent and water/ethanol as non-solvents.
• Preparation of membranes from cellulose acetate (CA), polyimide (PI), CTA, polyethersulfone (PES), and polysulfone (PSU).
• Characterization using scanning electron microscopy (SEM), viscosity measurements, and cloud point determination.

Main Results:

• CTA membranes in GVL with water as non-solvent exhibited excellent performance.
• Increasing CTA concentration (10-17.5 wt%) reduced permeance (15.9 to 5.5 L/m²·h·bar) but maintained high Rose Bengal (RB) rejection (>94%).
• Hansen solubility parameters, viscosity, and cloud point data provided insights into the phase inversion process.

Conclusions:

• GVL is a viable green solvent for fabricating high-performance NF membranes.
• CTA membranes show significant potential for sustainable nanofiltration applications.
• Understanding the interplay of solvent properties and process parameters is key to optimizing membrane performance.