The selective adsorption of C2H6 and C2H2 over C2H4 from C2H2/C2H4/C2H6 ternary mixtures for one-step C2H4 purification represents a crucial yet challenging task in industry. The pore structure of the adsorbents must be finely tailored to meet the demanding requirements for the separation considering the very similar physicochemical properties of the three gases. Herein, we report a Zn-triazolate-dicarboxylate framework, HIAM-210, featuring a novel topology which possesses one-dimensional channels decorated with adjacent uncoordinated carboxylate-O atoms. The suitable pore size and customized pore environment enable the compound to selectively capture C2H6 and C2H2 with high C2H2/C2H4 and C2H6/C2H4 selectivities of both 2.0. Breakthrough experiments show that polymer-grade C2H4 can be directly harvested from C2H2/C2H4/C2H6 (34/33/33 and 1/90/9) ternary mixtures. The underlying mechanism of the preferential adsorption was uncovered by grand canonical Monte Carlo simulations and DFT calculations.
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