▎ 摘　　要

NOVELTY - Gas separation membrane comprises: a porous support (21); and a gas separating active layer (22) disposed on the porous support and comprising a functionalized graphene. USE - The gas separation membrane is useful in a gas separator for separating: hydrogen and carbon dioxide; hydrogen and carbon monoxide; hydrogen and methane; hydrogen and nitrogen; helium and nitrogen; nitrogen and carbon dioxide; and/or methane and carbon dioxide (all claimed). ADVANTAGE - The gas separation membrane: has a high gas permeation rate and excellent selectivity for selected gas mixtures; exhibits improved processability and modularity; and can be prepared easily. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing a gas separation membrane, comprising: providing a composition comprising a functionalized graphene and a solvent; disposing the composition on a porous support to form a coating; and drying the coating to form a gas separating active layer comprising the functionalized graphene on the porous support. DESCRIPTION OF DRAWING(S) - The figure illustrates a schematic cross-sectional view of a gas separation membrane. Porous support (21) Gas separating active layer (22)