High-Permeance Room-Temperature Ionic-Liquid-Based Membranes for CO sub(2)/N sub(2) Separation

We have developed and fabricated thin-film composite (TFC) membranes with an active layer consisting of a room-temperature ionic liquid/polymerized (room-temperature ionic liquid) [i.e., (RTIL)/poly(RTIL)] composite material. The resulting membrane has a CO sub(2) permeance of 6100 plus or minus 400 GPU (where 1 GPU = 10 super(-6) cm super(3)/(cm super(2) s cmHg)) and an ideal CO sub(2)/N sub(2) selectivity of 22 plus or minus 2. This represents a new membrane with state-of-the-art CO sub(2) permeance and good CO sub(2)/N sub(2) selectivity. To our knowledge, this is the first example of a TFC gas separation membrane composed of an RTIL-containing active layer.