A thermostable calcium-based metal-organic framework for efficient capture and separation of acetylene from ternary mixture

High-efficiency and eco-friendly selective separation of C2H2 from industrial gaseous mixtures such as CO2 and CH4 is of great importance in the purification and production of downstream commodity chemicals. Herein, we report a thermostable calcium-based metal-organic framework, namely NUM-20, which could preferentially capture C2H2 from C2H2-containing gaseous mixtures. NUM-20 exhibits a higher capacity and preferential adsorption behavior of C2H2 versus the competing gases including CO2 and CH4, as reflected by single component gas sorption isotherms and the heat of adsorption. The IAST selectivity calculations indicate that NUM-20 possesses multiple component separation capacity, and the transient breakthrough simulations were performed to validate the capture and separation of C2H2 from multiple components. Furthermore, computational simulations were carried out to unveil the host-guest interactions under the molecular-level. This study on Ca-based MOF materials will enrich the three-dimensional Ca-based MOF adsorbents for gas capture and separation applications and address the industrial challenging separation process.