Density and Viscosity of Binary Mixtures of Tetraethylenepentamine or Pentaethylenehexamine with Methyldiethanolamine and Water

The density and viscosity of four binary mixtures, including tetraethylenepentamine (TEPA)/H2O, pentaethylenehexamine (PEHA)/H2O, TEPA/N-methyldiethanolamine (MDEA), and PEHA/MDEA, were measured from 303.15 to 343.15 K at atmospheric pressure (97.8 kPa). The measurements were carried out using a vibrating-tube viscometer and an Ubbelohde capillary viscometer. The Jouyban–Acree model was employed to correlate the experimental density data. Meanwhile, a modified Jouyban–Acree model was proposed in this work to regress the viscosity results. In addition, the calculated excess molar volume VmE and the viscosity deviation Δη from the experimental data were correlated by the Redlich–Kister model, and the detailed analysis was presented. The results of the present work are conducive to the further application of TEPA/H2O, PEHA/H2O, TEPA/MDEA, and PEHA/MDEA solutions in CO2 capture.