Measurement and prediction of the density of aqueous ternary mixtures of methyldiethanolamine and diethanolamine at temperatures from 25°c to 80°c

Densities have been measured for mixed aqueous solutions of N-methyldiethanolamine (MDEA) and diethanolamine (DEA) at 25, 30,40,50, 60,70, and 80°C. The compositions of the ternary solutions are near 30 mass% solute, because of industrial applications for the absorption of acid gases. The isopycnotic (same density) method, for predicting densities of multicomponent aqueous systems at 25°C has been used to predict the densities of the present non-electrolyte mixed solutions at other temperatures. Predicted and observed density values are in good agreement (<0.06% error). The method has also been used to predict densities of some aqueous sea salt mixtures at temperatures ranging from 5 to 95°C. Again the predicted and observed values are in good agreement (generally <0.1% error). On a mesure la masse volumique de solutions aqueuses mixtes de N-methyldiethanolamine (MDEA) and de diethanolamine (DEA) a 25, 30, 40, 50, 60, 70 et 80 °C. Les compositions des solutions ternaires sont des solutes de pres de 30% en masse, en raison des applications industrielles pour l'absorption des gaz acides. On a utilise la methode isopycnotique (masse volumique egale) qui a ete mise au point pour predire la masse volumique des systemes aqueux multicomposants a 25°C, pour predire la masse volumique des solutions mixtes non electrolytiques considerees a d'autres temperatures. Les valeurs de masse volumique predites et les valeurs observees montrent un bon accord (marge d'erreur <0,06%). On a egalement eu recours a cette methode pour predire la masse volumique de melanges de sel de mer aqueux a des temperatures allant de 5 a 95 °C. La encore, les valeurs predites et les valeurs observees sont concordantes (marge d'erreur generalement < 0,1%).