Metal-organic frameworks(MOFs)constructed from metal ions or metal clusters and organic ligands are a unique class of porous materials exhibiting important applications in the storage,separation and purification of gases relevant to their well-defined porosity.Herein a novel compound,[Ni(DCPTP)]n(termed Ni-DCPTP),based on the 4′-(3,5-dicarboxyphenyl)-2,2′,6′,2″-terpyridine(DCPTP2-)ligand was presented.Ni-DCPTP is a three-dimensional(3D)framework with a ths topology featuring one-dimensional(1D)helical channels.Ni-DCPTP shows an efficient removal trace C2H2 from C2H4 gas(1/99 mixture)with an excellent C2H4 productivity demonstrated by the transient breakthrough simulations in column adsorption processes.The efficient separation of C2H4 from C2H2/C2H4 mixture was further confirmed by the experimental column breakthrough studies,which show that the polymer-grade C2H4 gas(C2H2 < 40 ppm)can be obtained from Ni-DCPTP.The carboxylate oxygens exposed on the 1D pore channels serve as the preferential binding sites for C2H2 molecules,resulting in the efficient C2H2/C2H4 separation,which is corroborated by the density functional theory calculations.Thus an elegant example with carboxylate oxygenfunctionalized pore channels for effective C2H2/C2H4 separation is presented.