Investigation on novel deep eutectic solvents with high carbon dioxide adsorption performance

Deep eutectic solvents (DESs), which are compounds tightly linked by hydrogen bonds between two or three components, offering their straightforward preparation process and reasonably low costs and significant advantages for CO2 capture. Here, nine new types of DESs were successfully synthesized, all of which used triethylene diamine (DABCO) as the key hydrogen bond acceptor (HBA) and either diethylene glycol (DEG), 1,2propanediol (1,2-PD), or 1,3-propanediol (1,3-PD) as the hydrogen bond donor (HBD). The density and viscosity of the synthesized DESs were precisely measured, laying the groundwork for further research, and the solubility of CO2 in them was investigated when pressure and temperature were different. The experimental data were calculating using the Krichevsky-Kasarnovsky equation to gain insight into the adsorption mechanism and thermodynamic properties. Excitingly, the results show that DESs containing DABCO as the HBA possess outstanding CO2 adsorption and recycling capabilities, indicating their great potential for large-scale CO2 capture applications. This study not only enriches the scientific understanding of DESs, but also provides important technical support for future environmental protection efforts.