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 N2 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 Kcat/Km 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.