Above‐Tg Annealing Benefits in Nanoparticle‐Stabilized Carbon Molecular Sieve Membrane Pyrolysis for Improved Gas Separation

• Published in: Angewandte Chemie International Edition 2024-02, Vol.63 (8), p.e202317864-n/a
• Main Authors: Cao, Yuhe, Liu, Zhongyun, Koros, William J.
• Format: Article
• Language: English
• Subjects: Carbon dioxide; Carbon Molecular Sieves; Clean energy; Composite Membrane; Energy sources; Gas Separation; Green energy; Hollow Fiber Membranes; Hydrogen Separation; Membranes; Methane; Molecular sieves; Nanoparticles; Pyrolysis; Reluctance; Separation processes; Sol-gel processes
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202317864

Nanoparticles can suppress asymmetric precursor support collapse during pyrolysis to create carbon molecular sieve (CMS) membranes. This advance allows elimination of standard sol‐gel support stabilization steps. Here we report a simple but surprisingly important thermal soaking step at 400 °C in the pyrolysis process to obtain high performance CMS membranes. The composite CMS membranes show CO2/CH4 (50 : 50) mixed gas feed with an attractive CO2/CH4 selectivity of 134.2 and CO2 permeance of 71 GPU at 35 °C. Furthermore, a H2/CH4 selectivity of 663 with H2 permeance of 240 GPU was achieved for promising green energy resource‐H2 separation processes. Nano‐particle‐fillers were introduced to the core layer of the sheath‐core spun composite hollow fiber membranes to suppress the membrane matrix collapse during the pyrolysis. Defect healing hybridization gave a CMS membrane with extraordinary gas separation performance: CO2/CH4 selectivity of 134.2 with 71.1 GPU CO2 permeance as well as H2/CH4 selectivity of 662.6 with 239.6 GPU H2 permeance.