Defect Engineering in Metal-Organic Frameworks Towards Advanced Mixed Matrix Membranes for Efficient...

Area of Science:

• Materials Science
• Chemical Engineering
• Separation Technology

Background:

• Mixed-matrix membranes (MMMs) using metal-organic frameworks (MOFs) are promising for energy-efficient C3H6/C3H8 separation.
• Challenges include rational filler-matrix matching and improving separation performance.

Purpose of the Study:

• To introduce "defect engineering" in MOFs as a strategy to enhance MMM performance.
• To develop advanced MMMs with improved C3H6 permeability, selectivity, and stability.

Main Methods:

• Incorporation of defect-engineered MOFs into a polymer matrix to form MMMs.
• Gas transport, sorption, and material characterizations (including in situ FT-IR) were performed.
• Evaluation of MMM performance under industrial mixed-gas conditions.

Main Results:

• MMMs with defect-engineered MOFs exhibited exceptionally high C3H6 permeability.
• High C3H6/C3H8 selectivity was maintained, with enhanced stability under mixed-gas conditions.
• Defect sites facilitated ultrafast diffusion and favorable C3H6 sorption via complexation with open metal sites.

Conclusions:

• Defect engineering offers a versatile approach to designing advanced MMMs for gas separation.
• The strategy is applicable to different polymer matrices and gas pairs, indicating broad potential.
• This method significantly improves membrane performance and stability for industrial C3H6/C3H8 separation.