Mixed-Matrix Membrane Hollow Fibers of Cu₃(BTC)₂ MOF and Polyimide for Gas Separation and Adsorption

Metal−organic framework (MOF) crystals of Cu 3 (BTC) 2 with a high surface area (1396 m 2 ·g −1 ) were synthesized and mixed with polyimide (PI) to prepare mixed-matrix membranes (MMMs) for gas separations. The PI−Cu 3 (BTC) 2 blend was successfully spun into MMM hollow fiber by the dry/wet-spinning method. SEM images of the fiber cross sections revealed significant plastic deformation of the polymer matrix owing to the strong affinity between Cu 3 (BTC) 2 and PI. The H 2 permeance and the selectivity of H 2 with respect to other gases such as N 2, CO 2, O 2, and CH 4 both increased markedly with increased Cu 3 (BTC) 2 loading. At a loading of 6 wt % Cu 3 (BTC) 2, the permeance of H 2 increased by 45%, and the ideal selectivity increased by a factor of 2−3 compared to the corresponding values for pure PI.