Ebulliometric Determination of Vapor−Liquid Equilibria for Pure Water, Monoethanolamine, N-Methyldiethanolamine, 3-(Methylamino)-propylamine, and Their Binary and Ternary Solutions

Vapor−liquid equilibria (VLE) for binary and ternary aqueous solutions of water, monoethanolamine (MEA), N -methyldiethanolamine (MDEA), and 3-(methylamino)propylamine (MAPA) were measured in a modified Swietoslawski ebulliometer at (40, 60, 80, and 100) °C. Experimental temperature ( T ) and total pressure ( P ) were measured, and the compositions of both the liquid ( x ) and vapor ( y ) phases were analyzed. Boiling temperatures ( T b ) of pure water and amines were measured over the pressure range of P = (2.5 to 101.3) kPa. Experimental activity coefficients (γ) were calculated from the experimental P, T, x, and y data and were fit to the Wilson and NRTL equations.