Screening Deep Eutectic Solvents for CO2 Capture With COSMO-RS

• In this work, 502 experimental data for CO2 solubilities and 132 for Henry’s constantsof CO2 in DESs were comprehensively summarized from literatures and used for furtherverification and development of COSMO-RS. Large systematic deviations of 62.2, 59.6,63.0, and 59.1% for the logarithmic CO2 solubilities in the DESs (1:2, 1:3, 1:4, 1:5),respectively, were observed for the prediction with the original COSMO-RS, while thepredicted Henry’s constants of CO2 in the DESs (1:1.5, 1:2, 1:3, 1:4, 1:5) at temperaturesranging of 293.15–333.15 K are more accurate than the predicted CO2 solubility withthe original COSMO-RS. To improve the performance of COSMO-RS, 502 data pointsof CO2 solubility in the DESs (1:2, 1:3, 1:4, 1:5) were used for correcting COSMO-RSwith a temperature-pressure dependent parameter, and the CO2 solubility in the DES(1:6) was predicted to further verify the performance of the corrected model. The resultsindicate that the corrected COSMO-RS can significantly improve the model performancewith the ARDs decreasing down to 6.5, 4.8, 6.5, and 4.5% for the DESs (1:2, 1:3, 1:4, and 1:5), respectively, and the corrected COSMO-RS with the universal parameters can beused to predict the CO2 solubility in DESs with different mole ratios, for example, for theDES (1:6), the corrected COSMO-RS significantly improves the prediction with an ARD of10.3% that is much lower than 78.2% provided by the original COSMO-RS. Additionally,the result from COSMO-RS shows that the σ-profiles can reflect the strength of molecularinteractions between an HBA (or HBD) and CO2, determining the CO2 solubility, and thedominant interactions for CO2 capture in DESs are the H-bond and Van der Waals force,followed by the misfit based on the analysis of the predicted excess enthalpies.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Maskinteknik -- Energiteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Mechanical Engineering -- Energy Engineering (hsv//eng)

Keyword

deep eutectic solvents

CO2 capture

COSMO-RS

CO2 solubility

Henry's constant

Energiteknik

Energy Engineering

Publication and Content Type

ref (subject category)

art (subject category)