Small-pore CAU-21 and porous PIM-1 in mixed-matrix membranes for improving selectivity and permeability in hydrogen separation

Here, we report the fabrication of mixed-matrix membranes based on CAU-21 as the filler and PIM-1 as the matrix. The filler of the CAU-21 MOF with a crystallite size in the nanoscale and high uniformity was synthesized by a microwave-assisted approach. This small-pore CAU-21 was blended with a highly porous PIM-1 matrix to yield mixed-matrix membranes. The prepared membranes were applied for separating hydrogen from nitrogen and the results revealed very high selectivity of 127 for H-2 over N-2 and memorable H-2 permeability of 7199 Barrer.