Diffusivity of Nitrous Oxide in Aqueous Alkanolamine Solutions

The diffusivities of nitrous oxide (N 2 O) in aqueous alkanolamine solutions have been measured at (30, 35, and 40) °C. The systems studied are aqueous monoethanolamine, diethanolamine, diisopropanolamine, triethanolamine, and 2-amino-2-methyl-1-propanol solutions. The concentration of amine for monoethanolamine ranges from (1 to 5) kmol·m - 3 and for other amines from (0.5 to 2.5) kmol·m - 3 . The viscosities of diisopropanolamine and triethanolamine and the densities and viscosities of aqueous diisopropanolamine and triethanolamine solutions were also measured at (30, 35, and 40) °C. A simple correlation was used to correlate the diffusivity of N 2 O in amine solutions. The parameters of the correlation were determined from the measured diffusivity data and the available data in the open literature. The correlation has been shown to represent reasonably the diffusivity of N 2 O in six aqueous amine solutions: MEA, DEA, DIPA, MDEA, TEA, and AMP. The correlations are, in general, satisfactory for estimating the diffusivity of N 2 O in amine solutions, which in turn can be used to estimate the free molecular diffusivity of CO 2 in amines.