Measurement, modelling and molecular dynamics analysis for isobaric vapour-liquid equilibria of binary or ternary system (diethylamine, ethyl acetate, triethylamine)

Diethylamine, ethyl acetate and triethylamine are usually applied to synthesize an important flame retardant of vinylphosphorus, which has high ability to retard flames, low toxic content, and good washing durability. The isobaric VLE data of (diethylamine + triethylamine, diethylamine + ethyl acetate) and (ethyl acetate + trimethylamine) system were determined at 101.3 kPa for industrial separation. A minimum azeotrope was discovered at x = 0.8217 in the (ethyl acetate + trimethylamine) system. Therefore, a series of experiments were designed to investigate the effect of diethylamine on the (ethyl acetate + trimethylamine) system and the results indicated that the azeotrope can be eliminated when the liquid mole fraction of diethylamine is greater than 0.4687. Furthermore, molecular dynamics analysis through GROMACS software and Multiwfn software was also used to study the interaction of these three materials in this work. The results show that the weak interaction force around ethyl acetate decreases after adding diethylamine, which means that the van der Waals effect and the electrostatic effect of ethyl acetate become smaller. This may be the main reason why the azeotropic point of the (ethyl acetate + trimethylamine) system disappears.