Microporous polymer adsorptive membranes with high processing capacity for molecular separation.

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Membrane separation faces a trade-off between permeability and selectivity.
• Highly porous materials often lack processability and stability for adsorption-based separations.

Purpose of the Study:

• To develop a novel membrane adsorption material for selective separation of small organic molecules from water.
• To achieve ultrahigh processing capacity and overcome existing limitations in membrane technology.

Main Methods:

• Modification of a polymer of intrinsic microporosity (PIM) with hydrophilic amidoxime groups to create AOPIM-1.
• Fabrication of AOPIM-1 into a membrane for adsorption and separation experiments.
• Evaluation of membrane performance using Rhodamine B and various nano-sized organic molecules, measuring adsorption capacity and water flux.

Main Results:

• The AOPIM-1 membrane exhibited an ultrahigh adsorption capacity for Rhodamine B (26.114 g m⁻²), significantly exceeding previously reported adsorptive membranes.
• Achieved >99.9% removal of various nano-sized organic molecules.
• Demonstrated a water flux two orders of magnitude higher than typical pressure-driven membranes with similar rejection rates.

Conclusions:

• Hydrophilic amidoxime modified polymer of intrinsic microporosity (AOPIM-1) is a feasible material for high-capacity membrane adsorption.
• This work presents a promising adsorptive membrane for efficient molecular separation from water.
• The developed membrane technology offers a potential solution for water purification and molecular separation challenges.