Density, viscosity, and excess properties of MDEA + H2O, DMEA + H2O, and DEEA + H2O mixtures

Abstract

This study presents measured density and viscosity of N-methyldiethanolamine (MDEA) + H2O, Dimethylethanolamine (DMEA) +H2O, and Diethylethanolamine (DEEA) +H2O mixtures. The density was measured at amine mass fraction w1 from 0.3 to 1 for the temperature range 293.15-353.15 K. The excess molar volumes VE were determined from density data. Redlich-Kister type polynomials were proposed to fit VE and density deviation ln(ργ) to represent measured densities. The viscosity was measured at amine mass fraction w1 from 0.3 to 1 for the temperature range 293.15-363.15 K. The viscosity deviation ηE and excess free energy of activation for viscous flow ΔGE* were determined from measured viscosities and examined for intermolecular interactions among mixture molecules. Correlations were proposed to fit viscosity data with acceptable accuracies. The McAllister's three-body model was adopted to fit kinematic viscosities determined from density and dynamic viscosity data. The results showed the importance of examining intermolecular interactions that are discussed in McAllister's four-body model to improve the accuracies of data fits.