Microporous Metal-Organic Framework with Dual Functionalities for Efficient Separation of Acetylene from Light Hydrocarbon Mixtures

Separating acetylene from light hydrocarbon mixtures like ethylene is a very important process for downstream industrial applications. Herein, we report a new MOF [CuL2(SiF6)] (UTSA-220, L = (1E,2E)-1,2-bis(pyridin-4-ylmethylene)hydrazine) with dual functionalities featuring optimal pore size with strong binding sites for acetylene. UTSA-220 exhibits apparently higher uptake capacity for C2H2 than those for other light hydrocarbons. The potential of this material for trace C2H2 removal from C2H4 has also been demonstrated by a dynamic breakthrough experiment performed with C2H2/C2H4 (1/99 v/v) under simulated industrial conditions. According to the dispersion-corrected density functional theory (DFT-D) simulation, SiF62- and azine moieties serve as preferential binding sites for C2H2, indicating the feasibility of the dual functionalities incorporated in UTSA-220 for adsorbent-based C2H2 separations.