Mixed polymer fragment membranes on large‐area tubes for high‐performance <scp> H ₂ </scp> purification

Abstract High‐performance H 2 /CO 2 separation with good scalability is needed in industry. Here, we fabricated mixed polymer fragment membranes on alumina tubes. The synergistic control of monomer diffusion rate promoted the formation of H 2 selective channels, thereby elevating the H 2 /CO 2 separation performance. The membranes, each with an area of 37.7 cm 2 , demonstrated a high H 2 /CO 2 selectivity of 22.5 (with a corresponding H 2 permeance of 209 GPU) at 150°C and 2 bar, high pressure resistance (H 2 permeance and H 2 /CO 2 selectivity were 212 GPU and 11.1 at 200°C and 10 bar, respectively), and good reproducibility. Furthermore, we studied the effects of sweep gas, permeate pressure, reuse of substrates, and H 2 O and H 2 S contaminants on membrane performance, pointing out that the membranes can be well adapted to industrial relevant conditions. In addition, a two‐stage membrane system was designed to produce high concentration H 2 with a good yield.