Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

ABSTRACT

Dibutyl citrate (DBC) was synthesized via partial esterification of citric acid (CA) with n-butanol (BuOH), and characterized for the first time. Then, the monoacid diester was isolated from the reactive mixture by using a pH-controlled solvent extraction procedure. The identity of the obtained product was verified by NMR spectroscopy, and it was characterized by thermogravimetric and differential scanning calorimetry analysis, and by density and viscosity measurements. As per the calorimetric analysis, DBC exhibited a crystallization point below 213K, a boiling point of 412K, a decomposition temperature of 541K, and an average heat capacity of 2.850 kJ/kg K in the evaluated temperature range (315 - 355 K). The average liquid density and viscosity in the studied temperature interval (298 - 313 K) were 1.122 g/cm3 and 2.03 Pas, respectively. Additionally, isothermal vapor-liquid equilibrium data (P-x) in mixtures containing the obtained DBC and BuOH were measured at 313, 323 and 333 K. Experimental data were used to fit UNIQUAC interaction parameters for the binary DBCBuOH. The regressed model showed good agreement with experimental results, making it suitable for further process design and simulation. The obtained data can be used in the development of processes for citrate plasticizers production, and in the development of separation processes for DBC.