Constructing C2H2 anchoring traps within MOF interpenetration nets as C2H2/CO2 and C2H2/C2H4 bifunctional separator

Abstract

Efficient separation of C2H2/CO2 and C2H2/C2H4 is necessary and challenging for industrial processes. The traditional method of pore sieving has great limitations for separating gases with similar characteristics. Herein, we report a new case (UPC-80) with the help of C2H2 anchoring traps constructed by 4-fold interpenetration nets for gas separation. The single-component adsorption isotherms indicate that UPC-80 adsorbs more C2H2 than C2H4 and CO2, resulting in high adsorption selectivities of 6.34 and 4.78 for C2H2/CO2 and C2H2/C2H4 at 298 K, respectively. Laboratory-scale fixed-bed breakthrough experiments verify the efficient separation ability of UPC-80 toward the C2H2/CO2 and C2H2/C2H4 gas mixtures, remaining separation stability with negligible capacity loss. Theoretical simulations confirm that the good separation performance can be attributed to the anchoring of C2H2 by two Tb2(COO)6 clusters in adjacent interpenetration nets, as well as the strong electrostatic interaction. UPC-80 makes the first exploration to obtain specific C2H2 binding sites by interpenetrated networks, becoming an excellent candidate as porous adsorbent for separating C2H2/CO2 and C2H2/C2H4.