Deep eutectic solvent-modified hydrotalcite for carbon dioxide capture: A new generation of hybrid sorbents

The critical demand for effective CO 2 capture methods is highlighted by the mitigation of greenhouse gas emissions, particularly CO 2 .This is indicative of their significant influence on human well-being and global ecosystems, as well as their essential involvement in climate change.The adsorption method is a popular technique for capturing and storing CO 2 .This technique demands the use of an adsorbent, one of which is hydrotalcite (HT).The impregnation of HT with deep eutectic solvents (DES) can improve its adsorption capacity.In this study, a DES composed of choline chloride (ChCl) and monoethanolamine (MEA) at a mole ratio of 1:4 was used to modify the prepared HT by the combustion-recrystallization (HTR)-impregnation (HTI) procedure employing aluminum and magnesium nitrate precursors and carbonate solutions with a 20 wt.% DES loading.Comprehensive characterization was carried out through Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscope (FESEM), and Energy-Dispersive X-ray (EDX) analysis to identify the deviations in covalent chemical bonds of molecules, surface morphology, and elemental composition of the prepared adsorbents.The FTIR results confirmed interactions between DES functional groups and the hydroxyl layers of hydrotalcite, while SEM and EDX analyses revealed surface modification and changes in elemental composition.Remarkably, the impregnated HTI with DES exhibited a good CO 2 adsorption capacity of 0.46 mmol/g at room temperature and 1 bar.Furthermore, a remarkable recyclability validates the potential of DES-impregnated hydrotalcites for advanced CO 2 capture applications.