Rationalizing the Efficiency of HKUST-1 for Capture and Biomimetic Sequestration of CO2

In light of their outstanding properties, metal-organic frameworks appear to be the latest and most assured sorbent in CCUS technology. In this study, adsorption isotherms of pure CO2, CH4, and N-2 at three different temperatures were obtained for HKUST-1, and it showed a maximum CO2 adsorption uptake of 8.25 mmol g(-1) at 298 K and 30 bar. HKUST-1 was also employed as support to immobilize carbonic anhydrase (CA) derived from the bovine erythrocytes through cross-linked enzyme aggregates. CO2 hydration as well as its transformation into CaCO3 was studied using the CA immobilized HKUST-1 (CA/HKUST-1). The biocatalytic activity, thermal stability, reusability, and storage stability of CA/HKUST-1 were evaluated through para-nitrophenyl acetate hydrolysis. CA immobilized on HKUST-1 exhibits a fairly low K-cat/K-m value than the free CA; regardless of the above, the reusability of CA/HKUST-1 for about 20 cycles makes it a suitable biocatalyst of CO2 hydration under industrial operating conditions. The results demonstrated HKUST-1 as potential support for CA immobilization for CO2 sequestration and high CO2 uptake adsorbent.