Regulating the Layered Stacking of a Covalent Triazine Framework Membrane for Aromatic/Aliphatic Separation

Area of Science:

• Materials Science
• Chemical Engineering
• Separation Science

Background:

• Membrane separation of aromatics and aliphatics is vital for chemical and petroleum industries.
• Existing membranes struggle with harsh solvents, specificity, and processability.
• Aromatic/aliphatic separation is challenging due to similar molecular properties.

Purpose of the Study:

• To develop a novel covalent triazine framework (CTF) membrane for selective aromatic/aliphatic separation.
• To address the limitations of current membrane materials in demanding industrial environments.
• To achieve efficient all-liquid phase separation of aromatic and aliphatic mixtures.

Main Methods:

• Fabrication of a CTF membrane using a mix-monomer strategy (spatial and planar monomers).
• Modulation of pore aperture and membrane affinity for selective permeation.
• Investigation of separation mechanisms, including size sieving and molecular affinity.

Main Results:

• Achieved preferential permeation of aromatics over aliphatics (MW < 200 Da).
• Demonstrated successful all-liquid phase separation of aromatic/aliphatic mixtures.
• Confirmed the synergistic role of size sieving and membrane affinity in separation.
• Exhibited remarkable membrane robustness under various operating conditions.

Conclusions:

• The novel CTF membrane effectively separates aromatic and aliphatic mixtures via combined size sieving and affinity effects.
• The mix-monomer strategy provides a versatile approach for designing molecule-selective membranes.
• This work represents a significant advancement in membrane technology for separating small organic molecules.