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

Abstract

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.