Experimental investigation of density, viscosity and intermolecular interaction of binary system 1,3-butanediol + 1,2-ethanediamine for CO2 capture

In our recent work, the binary system of 1,3-butanediol (BTD) (1) + 1,2-ethanediamine (EDA) (2) shows strong solubility to CO2 with 0.7551 mol CO2 per mol EDA. In this work, as important thermodynamic properties, densities (ρ) and viscosities (η) of the binary system of BTD (1) + EDA (2) at T = (298.15, 303.15, 308.15, 313.15, and 318.15) K were carefully measured as a function of composition over the whole concentration range under atmospheric pressure. Based on the experimental ρ and η data, the excess properties of the BTD (1) + EDA (2) mixtures, including excess molar volume (VmE) and viscosity deviation ∆ η, apparent molar volume (Vφ,1 and Vφ,2), partial molar volume (V1¯and V2¯), and isobaric thermal expansion coefficient αρ were systemically investigated. Meanwhile, the Redlich-Kister equation was used to fit with VmE and ∆ η, the optimal fitting coefficients were obtained, and the standard deviations σ between the experimental and calculated quantities were evaluated. Additionally, the intermolecular interaction of BTD with EDA was expressed as the N ⋅⋅⋅H hydrogen-bonding interaction with the form of ⋯ HOCH(CH3)CH2CH2OH ⋯ NH2CH2CH2N(H2)⋯ on the basis of UV-vis, FTIR, 1H NMR, and Fluorescence spectral results and electrical conductivity of BTD (1) + EDA (2) mixtures.