Experiment and model for the surface tension of MEA-PEG400 and DEA-PEG400 aqueous solutions

• The surface tensions of PEG400 and amine-PEG400 aqueous solutions were measured.
• The experiments were modeled satisfactorily by using a thermodynamic equation.
• The temperature dependence of the surface tension was illustrated.
• The effects of the mass fractions of amines and PEG400 were demonstrated.

The surface tension (γ) of monoethanolamine (MEA)-poly(ethylene oxide) 400 (PEG400) and diethanolamine (DEA)-PEG400 aqueous solutions was measured by using the BZY-1 surface tension meter. The temperatures ranged from (298.2 to 323.2) K. The mass fraction of amines and PEG400, respectively, ranged from 0.20 to 0.30 and from 0 to 0.10. A thermodynamic equation was proposed to model the surface tension of the binary and ternary mixtures. The calculated results agreed well with the experiments. The effects of temperature, mass fraction of amines and PEG400 on the surface tension were demonstrated on the basis of experiments and calculations.