(149a) Practical Membranes for CO2 Capture

Membrane technology has advanced greatly in the last 10 years, and due to its potential cost advantages, membranes are now being applied to a wide variety of processes. One of the major focal points for research is in the utility of membranes in CO₂ separations, particularly in coal gasification plants.

Our research examines supported ionic liquid membranes (SILMs) and mixed matrix membranes (MMMs) in both flat and hollow fiber configurations.  NETL’s membrane development team includes researchers from a wide variety of backgrounds including computational modeling, materials synthesis, membrane fabrication, performance testing, and systems analysis.

SILMs were chosen for their improved transport properties.  Gas diffusivities in the IL transport media are higher than those observed in polymers leading to greater permeabilities.  More importantly, the materials are stable at elevated temperatures and have negligible vapor pressure, making them suitable for gasification applications.  Earlier testing of the various SILMs demonstrated their stability for gas separations at 300°C, and other modifications increased permeability and selectivity.  While the studies have demonstrated the potential for laboratory gas separation, the work is expanding to include performance studies under more realistic gas compositions. The presentation will detail evolution of the SILM technology from inception toward practicality.