Separation Effects of Renewable Solvent Ethyl Lactate on the Vapor–Liquid Equilibria of the Methanol + Dimethyl Carbonate Azeotropic System

Abstract

Ethyl lactate, which is an expected renewable solvent, was tested as an entrainer candidate for the separation of the binary methanol + dimethyl carbonate (DMC) azeotropic system by extractive distillation. Isobaric vapor–liquid equilibria (VLE) for two binary constituent systems, that is, methanol + DMC and DMC + ethyl lactate of the methanol + DMC + ethyl lactate ternary system, were determined by an ebulliometric method at pressures of (40.00 to 101.3) kPa. The experimental VLE data were fitted by the nonrandom two-liquid (NRTL) model. Predictions of the binary systems were also performed by the NIST-modified universal functional activity coefficient (UNIFAC) group contribution model. The separation effects of ethyl lactate were examined by two methods: residue curve map and relative volality α12 using the binary NRTL parameters. Both sets of calculated results indicated that ethyl lactate can be used as entrainer. Compared to other entrainers reported in the previous works, ethyl lactate would be a more potential entrainer for breaking the methanol + DMC azeotropic system by extractive distillation, considering not only the minimum liquid mole fraction of the entrainer, but also the corresponding boiling point of the ternary system, viscosity, molecular weight, and price. Finally, the measurements of VLE for the methanol + DMC + ethyl lactate ternary system were also done, and these behaviors were compared with the predictions using binary NRTL parameters and the NIST-modified UNIFAC model.

Isobaric Vapor–Liquid Equilibrium Measurements of Binary Systems of Dimethyl Carbonate with Dimethyl Sulfoxide, Anisole, and Diethyl Oxalate at 101.3 kPa

“…Meanwhile, the relative volatility (α 12 ) can be calculated using eq . where y and x refer to the mole fraction of component 1 or 2 in the vapor phase and liquid phase.…”

“…In this work, the experimental VLE data for the four binary systems DMC + dimethyl sulfoxide/anisole/diethyl oxalate and methanol + diethyl oxalate were measured. The excess Gibbs energy and relative volatility of the four binary systems were calculated. Then, the Van Ness point-to-point test , and infinite dilution test were applied to test the thermodynamic consistency of the measured VLE data for the binary systems.…”

Recycling of End‐of‐Life Poly(bisphenol A carbonate) via Alkali Metal Halide‐Catalyzed Phenolysis

“…Conversely, the second product dimethyl carbonate and methanol forms an azeotrope, which requires some efforts for separation. [20] A potentially more attractive approach is the use of phenol as depolymerization reagents, while forming bisphenol A and diphenyl carbonate as products, which are the components for one of the major industrial synthesis of poly(bisphenol A carbonate) (1) (Scheme 1). However, only a few numbers of reactions following this path have been accounted so far, requiring long reaction times and/ or "complicated" catalysts.…”

“…Next, the loading of potassium fluoride was studied, revealing still good performance at 0.5 mol % with a yield of 58 % for 2, while in the absence of KF no reactivity was observed ( Table 1, entries 1, 6-11). Furthermore, in the absence of THF a decrease of the yield was observed, demonstrating the need for THF ( [20][21][22][23][24][25]. Comparable yields to KF were detected for KI and NaI, while other salts resulted in the formation of 2 in moderate yields.…”

Isobaric Vapor–Liquid Equilibrium of Binary Systems of 1-Pentanol + Butyl Butyrate, 1-Pentanol + N-Formylmorpholine, and p-Xylene + Butyl Butyrate at 101.3 kPa

“…Finally, the binary interaction parameters of three activity coefficient models, the nonrandom two-liquid (NRTL), universal quasichemical (UNIQUAC), and Wilson models, are regressed by Aspen Plus . Due to the reliability of the experimental results, the relative volatility of the binary system is accurately calculated to select the best solvent for the separation of PX/1-pentanol.…”