A convenient and effective approach has been developed to prepare carbon molecular sieve (CMS) membranes derived from poly(furfuryl alcohol) with high O2/N2 separation performance in this paper.The CMS membranes is formed by coating a thin layer of viscous poly(furfuryl alcohol) liquid

which was synthesized by polymerization of furfuryl alcohol by oxalic acid catalyst

on a porous coal-based tubular support followed by controlled pyrolysis.TGA

XRD

SEM and gas permeation experiments are employed to give an insight into pyrolysis process

morphological characteristics and separation performance of CMS membranes.The results show that the CMS membranes with a continuous defect-free coating exhibit an excellent O2/N2 separation performance.The increase in the final pyrolysis temperature from 600℃ to 900℃ results in a decrease in the d-spacing of the interlayers of graphitic carbon planes and the shrinkage in size of ultramicropores

which leads to the reduction in permeabilities of O2 and N2 and improvement in O2/N2 permselectivity.It can also be found that the correlation points for all CMS membranes prepared in the present work fall above the Robeson’s upper bound limit that is uncommon for polymeric membranes.These results indicate that poly(furfuryl alcohol)based CMS membranes obtained from the novel method are of great potential for O2 and N2 separation.