The effective separation of carbon dioxide (CO2) from acetylene (C2H2) in a gas mixture (CO2/C2H2) during the purification process is an important industrial demand since C2H2is widely used in chemical products but is challenging due to the similar physicochemical properties of both gases. Herein, we report highly selective chemisorptive CO2/C2H2separation using diamine-appended metal-organic frameworks (MOFs) with strong acid-base interactions between CO2and amine groups, enabling specific recognition of CO2over C2H2. These functionalized MOFs exhibited preferential uptake of CO2over C2H2at 298 K and 1 bar. They showed the highest CO2adsorption capacities (3.58-3.82 mmol g−1) at 30 mbar, which is the partial pressure of CO2during the C2H2purification process. Furthermore, the adsorption selectivity and recyclability of these MOFs for CO2over C2H2in the gas mixture were verified by dynamic breakthrough experiments. This work demonstrates that diamine-appended MOFs are promising adsorbents to produce high-purity C2H2by means of selective capture of CO2from a CO2/C2H2mixture.
ASJC Scopus subject areas
- Renewable Energy, Sustainability and the Environment
- Materials Science(all)