Interphase Surface Stability in Liquid-Liquid Membrane Contactors Based on Track-Etched Membranes

Area of Science:

• Chemical Engineering
• Materials Science
• Separation Processes

Background:

• Liquid-liquid membrane contactors offer a promising approach for extraction processes.
• Component transfer occurs within membrane pores between immiscible liquids.
• Highly asymmetric track-etched membranes (PET) with varying pore sizes were investigated.

Purpose of the Study:

• To evaluate the interface stability of asymmetric track-etched membranes in liquid-liquid contactors.
• To determine the influence of pore structure, membrane orientation, liquid velocities, and pressure drop on stability.
• To demonstrate the application of these membranes for impurity extraction.

Main Methods:

• Utilized highly asymmetric track-etched PET membranes with distinct pore sizes (12.5-19 nm vs. hundreds of nm).
• Investigated interface stability in water-pentanol and water-hexadecane systems under varying process parameters.
• Analyzed the effect of membrane orientation (aqueous phase supply side) and pressure drop.

Main Results:

• Interface stability increased with decreasing pore size.
• Optimal performance achieved when the aqueous phase was supplied from the side with larger pores.
• Asymmetric structure allowed a two-fold increase in stable pressure drop range (5 to 10 kPa).

Conclusions:

• Asymmetric track-etched membranes significantly enhance liquid-liquid interface stability in membrane contactors.
• Proper orientation and pore size control are crucial for maximizing operational pressure and preventing dispersion.
• These membranes provide an effective platform for liquid-liquid extraction, demonstrated by acetone removal from an organic phase.