Gas solubility of carbon dioxide in an aqueous solution of 32.5 wt.% N-methyldiethanolamine and 12.5 wt.% diethanolamine with 4, 6, and 10 wt.% 2-amino-2-methyl-1-propanol has been measured, at 313.15, 343.15, and 393.15 K, over a range of pressure from 3 to 2000 kPa, using a chromatographic method for analysis of the liquid phase. The results of the gas solubility are given as the partial pressure of CO2 against its mole ratio alpha (mol CO2/mol alkanolamine) and its mole fraction at each temperature studied. The solubility of CO2 in all the systems studied decreases with an increase in temperature and increases with an increase in the partial pressure of CO2 at a given temperature and it is a function of the concentration of the mixture of alkanolamines in solution. The enthalpy of solution of CO2 has been calculated from the experimental solubility data. (C) 2004 Elsevier B.V. All rights reserved.