Thermophysical modelling of transport and optical properties of 1-propanol+1,3-diaminopropane or 1,2-diaminopropane or 1-amino-2-- propanol binary liquid mixture at T=298.15-318.15 K: Molecular interaction analysis by density functional theory (DFT) and graph theoretical approach (GTA)

Background: Pure liquid properties cannot always satisfy the need of chemical processes. Therefore, liquid mixtures are preferred in different compositions, and the thermo-physical properties of liquid mixtures are highly significant for different processes. The present report involves thermo-physical of amines and 1-propanol. Amines are utilized for CO2 absorption processes.Methods: The viscosity (eta) and refractive index (nD) of 1P (1-propanol) (1) + Amines (1,3-DAP(1,3-dia-minopropane), 1,2-DAP(1,2-diaminopropane) and 1A2P(1-amino-2-propanol)) (2) binary mixture were measured at T = 298.15-318.15 K under the atmospheric pressure 0.1 MPa. Experimental data of eta and nD were further used to determine deviation in viscosity (Delta eta), excess Gibbs free energy of activation (G*E) and deviation in refractive index (Delta nD). Delta eta were analyzed by Bloomfield and Dewan model (BFD) and also examined in term of Graph theoretical approach (GTA). The eta and nD data were further correlated by various relevant correlations Significant findings: The derived thermo-physical properties were well correlated with Redlich-Kister polynomial equation. DFT studies indicated the strength of molecular interactions and supported the graph theory in pre-dicting probable associative molecular species in the liquid mixtures. Further, in 1P + amines binary liquid mixtures, the dominant interaction is OH--NH.