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Extracts of compounds fromMoringa oleifera leaves were obtained by supercritical extraction with CO 2 using ethanol as a cosolvent (scCO 2 + EtOH). The experimental conditions were investigated by varying temperature (35-80 C), pressure (15-25 MPa), and mass ratio between ethanol and raw material. The phenolic acids (gallic, vanillic, and p-coumaric acids) and flavonoids (catechin) were identified in all extracts, except for the extract obtained without the cosolvent. The main compounds by GC-MS were 1-triacontanol, nonacosane, heptacosane, phytol, γ-tocopherol, and α-tocopherol. Extracts obtained at 35 C showed the highest values of total phenolic compounds, DPPH, and FRAP, however, the lowest extraction yield. The central point extraction conditions (60 C and 20 MPa) had the best-combined results for yield (4.4%), total phenolic compounds (24 ± 1 mg GAE/g), DPPH (77 ± 2 μmol Trolox/g), FRAP (265 ± 9 μmol Trolox/g) and the presence of bioactive compounds. Practical ApplicationsSupercritical fluid extraction with CO 2 is a clean technology that employs low temperatures, producing high-quality extracts. Moringa oleifera leaf extracts showed different compositions according to the experimental conditions evaluated. The use of ethanol as a cosolvent and high temperatures positively influenced the extraction yield. All extracts showed antioxidant potential. Catechin, gallic, vanillic, and pcoumaric acids were the main phenolic compounds. The extract obtained at the central point condition had better antioxidant potential, yield, and bioactive compounds.

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As a part of a series of studies that aim to expand the experimental database used to assist the design of novel technologies in the field of subsea gas processing, 18 new vapor–liquid equilibrium data points were measured for the system triethylene glycol (1) + water (2) + methane (3) at 6.0 and 12.5 MPa, temperature range between 288 and 323 K, and a glycol content above 95 wt %. The new data include both gas [glycol (y 1) and water (y 2)] and liquid [methane solubility (x 3)] phase composition, with relative experimental uncertainties below 18%. It was observed that one of the experimental data sets available in the literature is not in agreement with the experimental data measured in this work. Furthermore, an important target was to reevaluate the cubic-plus-association (CPA) equation-of-state modeling capability, which has been previously used for triethylene glycol–methane systems. CPA using a 4C association scheme for TEG and one interaction parameter per binary has provided a good description of the newly measured data, with the average absolute relative deviation ranging between 9 and 43%. Binary interaction parameters regressed solely from the corresponding binary data were used for all ternary predictions with CPA.

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This study reports experimental data and kinetic modeling of acetic acid esterification with n‐pentanol using sulfated zirconia as a catalyst. Reactions were carried out in an isothermal well‐mixed batch reactor at different temperatures (50‐80°C), n‐pentanol to acid molar ratios (1:1‐3:1), and catalyst loadings (5‐10 wt% in relation to the total amount of acetic acid). The reaction mechanism regarding the heterogeneous catalysis was evaluated considering pseudo‐homogeneous, Eley–Rideal, and Langmuir–Hinshelwood model approaches. The reaction mixture was considered a nonideal solution and the UNIQUAC thermodynamic model was used to take into account the nonidealities in the liquid phase. The results obtained indicated that increases in the temperature and catalyst loading increased the product formation, while changes in the n‐pentanol to acetic acid molar ratio showed no significant effect. The estimated enthalpy of the reaction was −8.49 kJ mol−1, suggesting a slightly exothermic reaction. The Eley–Rideal model, with acetic acid adsorbed on the catalyst as the limiting step, was found to be the most significant reaction mechanism.

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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.