Solubility of nitrous oxide in alkanolamine aqueous solutions

The solubility of nitrous oxide (N2O) in alkanolamine aqueous solutions has been measured at (30, 35, and 40) degrees C. The systems studied are monoe thanolamine, diethanolamine, diisopropanolamine, triethanolamine, and 2-ami no-2-methyl-1-propanol aqueous solutions. The concentration of amine for mo noethanolamine ranges from (1 to 6) kmol.m(-3) and for other amines from (0 .5 to 3) kmol.m(-3). The accuracy of the measurement is estimated to be +/- 2%. A semiempirical model of the excess Henry's constant proposed by Wang et al. (1992) was used to correlate the solubility of N2O in amine solution s. The parameters of the correlation were determined from the measured solu bility data and the available data in the open literature. For a wide tempe rature range from (15 to 75) degrees C, the obtained correlation has been s hown to represent reasonably the solubility of N2O in six amine aqueous sol utions: MEA, DEA, DIPA, TEA, MDEA, and AMP. For the purpose of process desi gn, the obtained correlations are, in general, satisfactory for estimating the solubility of N2O in amine solutions, which in turn can be used to esti mate the correct free-gas solubility of CO2 in amines.