ZIF-11/Polybenzimidazole Composite Membrane with Improved Hydrogen Separation Performance

Zeolitic imidazolate framework (ZIF)-11 crystals were prepared by the toluene-assisted method, and they were incorporated into polysulfone, polyethersulfone, and polybenzimidazole (PBI) matrix to investigate the compatibility. ZIF-11 had a good connection with PBI matrix as they had the same benzimidazole groups. The evaporation temperature of the membrane formation was studied with two different solvents: N-methyl-2-pyrrolidone (NMP) and N, N-dimethylacetamide (DMAc). Then, the ZIF-11/PBI composite membranes prepared using NMP or DMAc as the solvent were characterized and tested by gas separation. Improved H-2 and CO2 permeabilities with a H-2/CO2 ideal selectivity of 5.6 were obtained on the 16.1 wt % ZIF-11/PBI composite membrane prepared with DMAc as the solvent. (C) 2014 Wiley Periodicals, Inc.