Attapulgite Nanorod-Incorporated Polyimide Membrane for Enhanced Gas Separation Performance

Area of Science:

• Materials Science
• Chemical Engineering
• Polymer Science

Background:

• Polyimide (PI) membranes offer excellent processability and mechanical properties for gas separation but face limitations in permeability and selectivity.
• Incorporating nanoparticles into polymer matrices is a key strategy to overcome these limitations and enhance membrane performance.

Purpose of the Study:

• To develop enhanced polyimide/nano-attapulgite (PI/ATP) composite membranes with improved gas separation properties.
• To investigate the effect of nano-attapulgite content on the gas permeability and selectivity of polyimide membranes.

Main Methods:

• Polyimide/nano-attapulgite (PI/ATP) composite membranes were synthesized via in-situ polymerization using nano-attapulgite functionalized with KH-550 silane coupling agent.
• Comprehensive characterization and gas permeation tests were performed on the synthesized membranes at various pressures.

Main Results:

• Increasing ATP content in PI membranes led to a significant rise in gas permeability for H2, He, N2, O2, CH4, and CO2.
• At 50% ATP content, gas permeabilities increased by over 119% compared to pure PI membranes, with no significant change in selectivity.
• The enhanced permeability is attributed to increased free volume caused by inefficient polymer chain stacking and interfacial voids.

Conclusions:

• The developed PI/ATP composite membranes demonstrate significantly improved gas permeability, making them highly suitable for gas separation.
• These membranes represent a promising advancement for applications in the industrial gas separation sector.