Solubility Parameter of Carbon Dioxide-An Enigma

Yizhak Marcus

doi:10.1021/acsomega.7b01665

Solubility Parameter of Carbon Dioxide-An Enigma

ACS Omega. 2018 Jan 17;3(1):524-528. doi: 10.1021/acsomega.7b01665. eCollection 2018 Jan 31.

Author

Yizhak Marcus¹

Affiliation

¹ Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.

Abstract

The solubility of gaseous carbon dioxide in a variety of solvents has been extensively studied, the solute interacting with most solvents via dispersion forces. Hence, its Hildebrand solubility parameter, δ_H, may be used to predict its dissolution in liquids. The usual definition of δ_H involves Δ_v H, the molar enthalpy of vaporization, strictly applicable to liquids. This expression is inapplicable for carbon dioxide, being a gas at the temperatures of technical interest (298 ≤ T/K ≤ 333), and various indirect methods have been employed for the determination of δ_H(CO₂,T). The appreciable polarizability of CO₂ and its ability to accept hydrogen bonds from suitable donor solvents prompted the determination of its Hansen solubility parameters. Finally, supercritical carbon dioxide has been extensively used as a solvent so that its δ_H(scCO₂,T,P) is a useful quantity to know. The large discrepancies between the reported quantities for δ_H(CO₂,T) are analyzed and discussed.