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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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