Effect of carbon molecular sieve on phenol formaldehyde novolac resin based carbon membranes

Carbon molecular sieve membrane (CMSM) was prepared by dip coating a phenol formaldehyde novolac resin (PFNR) based green membrane support with an ethanol solution containing PFNR and carbon molecular sieve (CMS). X-ray diffraction and nitrogen adsorption isotherms were employed to characterize the carbon structures. The results indicated that the CMSM shows high selectivity for separation of gases like O2/N2 and H2/CH4 system from pure gas permeation experiments. The permeation rate of H2, O2, and CO2 increases with the addition of CMS to the coating agent, while that of N2 and CH4 decreases. Correspondingly, the ideal separation factor of H2/CH4 enhances from 316 with a 50 wt.% PFNR ethanol solution as coating agent to 468 with a 50 wt.% PFNR ethanol solution involving CMS as coating agent, representing an increase of 48%. The addition of CMS redounds to the permeation of O2 and reduction of defect in the carbon membrane.