Liquid density, viscosity and spectroscopic studies of binary mixture of tetraethylene glycol + 1,2-ethanediamine for CO2 capture

Thermophysical properties for binary mixture of tetraethylene glycol (T4EG) (1) + 1,2-ethanediamine (EDA) (2), a potential scrubbing solution for the absorption of CO2, are very important as well as lacking in the literatures. This work reports densities and viscosities over the entire concentration range for the binary mixture at T = (293.15-318.15) K under atmospheric pressure. According to the experimental density and viscosity values, the mixtures’ excess molar volume (VmE), absolute viscosity deviation (∆η), excess free energies of activation (∆G*E), apparent molar volumes, partial molar volumes and isobaric thermal expansion coefficient were calculated, respectively. Meanwhile, the VmE, ∆η and ∆G*E values were fitted by a Redlich–Kister equation to obtain coefficients. To further study, the Fourier transform infrared, UV-Vis and fluorescence spectra of T4EG + EDA mixtures with various concentrations were measured, and the intermolecular interaction of T4EG with EDA was also discussed as the formation of –OCH2CH2O–H···N(H2)CH2CH2(H2)N···.