Above-T_g Annealing Benefits in Nanoparticle-Stabilized Carbon Molecular Sieve Membrane Pyrolysis for Improved Gas...

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.