Porous Polyethersulfone-Supported Zeolitic Imidazolate Framework Membranes for Hydrogen Separation

ZIF-8 thin layer has been synthesized on the asymmetric porous polyethersulfone (PES) substrate via secondary seeded growth. Continuous and dense ZIF-8 layer, containing microcavities, has good affinity with the PES support. Single gas permeance was measured for H 2, N 2, CH 4, O 2, and Ar at different pressure gradients and temperatures. Molecular sieving separation has been achieved for selectively separating hydrogen from larger gases. At 333 K, the H 2 permeance can reach ∼4 × 10 –7 mol m –2 s –1 Pa –1, and the ideal separation factors of H 2 from Ar, O 2, N 2, and CH 4 are 9.7, 10.8, 9.9, and 10.7, respectively. Long-term hydrogen permeance and H 2 /N 2 separation performance show the stable permeability of the derived membranes.