Modeling of Simultaneous Chemical and Phase Equilibria in Esterification of Acetic Acid with Ethanol in High-Pressure Carbon Dioxide

Abstract

This paper presents modeling of simultaneous chemical and phase equilibria (CPE) in esterification of acetic acid with ethanol in carbon dioxide at high pressure. Nine models based on the cubic equations of state (EOSs) have been applied. Four of them use classical mixing rules with or without the binary interaction coefficients k ij , one model treats this coefficient as a function of temperature and composition, and the last four methods apply the mixing rules combining EOS and excess Gibbs free energy models. Two procedures had to be applied to obtain the agreement between the calculated and experimental results. First, the thermodynamic data referring to the acetic acid Gibbs free energies of formation were corrected to describe precisely the literature experimental chemical equilibrium constants of the considered esterification reaction in the gas phase. Second, since the literature VLE data of the system CO 2 -ethyl acetate turned out to be inaccurate, the binary interaction coefficients of this mixture were fitted from the ternary VLE data of the system CO 2 -ethanol-ethyl acetate.

Kinetic Study of Acetic Acid Esterification with Methanol Catalyzed by Gel and Macroporous Resins

“…The reaction enthalpy was calculated at -4.39 kJ mol -1 , based on thermodynamic data obtained from the tabulated values of the NIST Chemistry Webbook. At 298 K the values for the corresponding equilibrium coefficient K eq ranging from 612.51 to 30.16 were published (5,(36)(37)(38)(39)(40)(41) Due to the non-ideal character of the reaction mixture, activity . coefficients for each component were calculated at temperatures ranging from 303 K to 333 K with the UNIQUAC method.…”

Enhanced Conversion in the Direct Synthesis of Diethyl Carbonate from Ethanol and CO2 by Process Intensification

“…The PRSV cubic equation state, Eq. (4), has been reported to adequately correlate the water-CO 2 [22], DEC-CO 2 [23], ethanol-CO 2 [24], ethanol-water [25], and CO 2 -ethanol-water [26] both at high and moderate pressures. Furthermore, Pineros et al [27] reported that PRSV describes adequately the binary and ternary subsystems of the DMC-methanol-H 2 O-CO 2 mixture and, thus, the authors used this equation of state to model the quaternary system.…”

Potential routes for thermochemical biorefineries

“…The same considerations as in the esterification with methanol are applicable for the catalyst . There are also studies on vapor‐phase esterification, including in a supercritical CO 2 atmosphere, but they are not commercially viable …”

“…139 Th ere are also studies on vapor-phase esterifi cation, including in a supercritical CO 2 atmosphere, but they are not commercially viable. 139,141,142 Hydrogenation (hydrogenolysis) of methyl or ethyl acetate is carried out with heterogeneous catalysts in fi xed-bed reactors. Various catalysts have been used for both reactions but at reaction conditions.…”