New High-Performance Porous Ionic Liquids for Low Pressure CO2 Capture

Porous ionic liquids are non volatile, versatile materials that associate porosity and fluidity. New porous ionic liquids, based on the ZIF-8 metal-organic framework and on phosphonium acetate or levulinate salts, were prepared and show an increased capacity to absorb carbon dioxide at low pressures. Porous suspensions based on phosphonium levulinate ionic liquid absorb reversibly 103% more carbon dioxide per mass than pure ZIF-8 per mass at 1bar and 303K. We show how the rational combination of MOFs with ionic liquids can greatly enhance low pressure CO2 absorption, paving the way toward a new generation of high-performance, readily available liquid materials for effective low pressure carbon capture.