Vapor pressure, vapor-liquid equilibria, liquid-liquid equilibria and excess enthalpy of the system consisting of isophorone, furfural, acetic acid and water

Extraction of 5-Hydroxymethylfurfural and Furfural in Aqueous Biphasic Systems: A COSMO-RS Guided Approach to Greener Solvent Selection

5-Hydroxymethylfurfural (HMF) and furfural (Fur) are promising biobased platform chemicals, derived from the dehydration of carbohydrate feedstocks, normally conducted in an aqueous phase. Plagued by side-reactions in such phase, such as the rehydration to levulinic acid (LA) and formic acid (FA) or self-condensation to humins, HMF and Fur necessitates diversification from monophasic aqueous reaction systems toward biphasic systems to mitigate undesired side-reactions. Here, a methodology based on the COnductor-like Screening MOdel for Real Solvents (COSMO-RS) method was used to screen solvent candidates based on the predicted partition coefficients (Ki). Hansen solubility parameters in conjunction with excess thermodynamic quantities determined by COSMO-RS were employed to assess solvent compatibility. Experimental validation of the COSMO-RS values highlighted only minor deviations from the predictions with root-mean-square-error (RMSE) values of HMF and Fur at 0.76 and 5.32, respectively, at 298 K. The combined effort suggested cyclohexanone, isophorone, and methyl isobutyl ketone (MIBK) as the best candidates. Finally, extraction solvent reuse demonstrated cyclohexanone suitability for HMF extraction with KHMF of 3.66 and MIBK for Fur with KFur 7.80 with consistent partitioning across four total runs. Both solvents are classified as recommended by the CHEM21 solvent selection guide, hence adding to the sustainability of the process.

Phase equilibria modeling of biorefinery-related systems: a systematic review

The search for sustainable ideas has gained prominence in recent decades at all levels of society since it has become imperative an economic, social, and environmental development in an integrated manner. In this context, biorefineries are currently present as the technology that best covers all these parameters, as they add the benefits of waste reuse, energy cogeneration, and fossil fuel substitution. Thus, the study of the various applicable biological matrices and exploring the technical capabilities of these processes become highly attractive. Thermodynamic modeling acts in this scenario as a fundamental tool for phase behavior predictions in process modeling, design, and optimization. Thus, this work aimed to systematize, using the PRISMA statement for systematic reviews, the information published between 2010 and 2020 on phase equilibria modeling in systems related to biorefineries to organize what is already known about the subject. As a result, 236 papers were categorized in terms of the year, country, type of phase equilibria, and thermodynamic model used. Also, the phase behavior predictions of different thermodynamic models under the same process conditions were qualitatively compared, establishing PC-SAFT as the model that best represents the great diversity of interest systems for biorefineries in a wide range of conditions.

Vapor-Liquid Equilibria Study of the LiCl + CaCl2 + H2O System

Vapor-liquid equilibrium (VLE) data are measured and reported for the LiCl + CaCl₂ + H₂O system. The experimental procedures were carried out with pressures between 6 and 101.3 kPa in a computer-controlled glass apparatus. We obtained the relationship between solubility of salt and vapor pressure by analyzing and summarizing the results. Then, a modified NRTL model based on the hypothesis of hydration was used in this paper. By correlation of literature and experimental data for LiCl + H₂O, CaCl₂ + H₂O, and LiCl + CaCl₂ + H₂O (pressure spanning from 5 to 101.3 kPa), some parameters were modified for improving the accuracy of the calculation. Meanwhile, the model was successfully applied to predict the VLE data in LiCl + CaCl₂ + H₂O systems with the modified binary parameters.