One-step ionic liquid-mediated dissolution-acetylation for high-performance regenerated cellulose ultrafiltration...

Area of Science:

• Materials Science
• Chemical Engineering
• Membrane Technology

Background:

• Cellulose-based ultrafiltration (UF) membranes face challenges with solubility and processability, limiting control over morphology and performance.
• Existing methods often require multiple steps, increasing complexity and cost.

Purpose of the Study:

• To develop a single-step protocol for fabricating regenerated cellulose (RC) UF membranes with tunable properties.
• To enhance membrane microstructure, performance, and fouling resistance through acetylation.

Main Methods:

• A one-step dissolution-acetylation protocol using the ionic liquid [BMIM]Cl was employed.
• Systematic variation of acetylation time and acetic anhydride concentration controlled the degree of substitution.
• Membrane performance was evaluated based on pure water flux, protein rejection, and mechanical properties.

Main Results:

• Regenerated cellulose membranes with substitution degrees ranging from 12.4% to 30.3% were successfully fabricated.
• The RC 20-36h membrane (30.3% substitution) exhibited high pure water flux (293.81 L·m⁻²·h⁻¹), good BSA rejection (83.44%), and excellent flux recovery (89.59%).
• Acetylation enhanced surface hydrophilicity (contact angle 17.79°) and mechanical strength (1059 kPa), while minimizing structural defects.

Conclusions:

• The single-step dissolution-acetylation approach provides a sustainable and efficient route to high-performance UF membranes.
• Tunable acetylation allows for optimized microstructure, balancing permeability, selectivity, and fouling resistance.
• This method offers precise control over membrane morphology and improved processability for cellulose-based UF applications.