Solubility and Diffusivity of N2O in Aqueous 4-(Diethylamino)-2-butanol Solutions for Use in Postcombustion CO2 Capture

In this work, the solubility and diffusivity of nitrous oxide (N2O) in aqueous 4-(diethylamino)-2-butanol (DEAB) solutions were measured. Solubility was measured in a stirred cell reactor over the temperature range of 298–343 K and concentration range of 0.68–3.77 M. On the other hand, diffusivity was measured in a laminar jet absorber over the temperature range of 298–318 K and concentration range of 1.0–2.5 M. An attempt was made to correlate the solubility data with well-known models (semiempirical model, Redlich–Kister equation, and polynomial model). It was observed that only the polynomial model correlated the solubility of N2O in aqueous DEAB solution satisfactorily with an AAD of 0.1%. Similarly, an attempt was made to correlate the diffusivity data with well-known models (semiempirical model and modified Stokes–Einstein model). The semiempirical model provided better predicted N2O diffusivity data compared with the experimental data with an AAD of 3.4%. These data can then be used to determine the physical solubility and physical diffusivity of carbon dioxide (CO2) in aqueous DEAB solutions using the “N2O analogy”.