Key words: transformation of pyrrole in supercritical water and hydrogen-oxygen fluid
The transformation of pyrrole in supercritical water and hydrogen-oxygen fluid in the flow mode (673-823 K, 25 MPa, acid excess coefficient ≤ 2.46, residence time 18-148 s) was investigated. It was found that in the absence of O2, an increase in temperature leads to an increase in the degree of transformation of pyrrole and the release of gaseous products (H2, CH4, CO and CO2). When pyrrole is oxidized in an oxygenated fluid, the oxygen excess coefficient has a greater effect on the degree of removal of organic carbon than the temperature. The products obtained at 723 and 773 K contain a solid whose IR spectrum corresponds to polypyrrole. In general, the oxidation of pyrrole in the hydrogen-oxygen fluid proceeds by the mechanism of parallel and sequential reactions, including the formation and oxidation of the products of the opening cycle, as well as the formation and oxidation of the polymerization products of pyrrole.
doi:10.34984/SCFTP.2022.17.3.002
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ГОСТ
7.0.100-2018
Transformation of pyrrole in supercritical water and hydrogen-oxygen fluid / – Текст : непосредственный // Сверхкритические Флюиды: Теория и Практика.. – 2022. – Т. 17. – № 3. – С. 7-18. - DOI:
TRANSLIT
Prevrashchenie pirrola v sverhkriticheskoj vode i vodokislorodnom flyuide / – Sverhkriticheskie Flyuidy: Teoriya i Praktika.. – 2022. – Т. 17. – № 3. – S. 7-18. - DOI:
En
Transformation of pyrrole in supercritical water and hydrogen-oxygen fluid. Sverhkriticheskie Flyuidy: Teoriya i Praktika, 3, 7-18 (2022). https://doi.org/
Key words: cobalt, super-stitched polystyrene, subcritical water
The composition and structure of a cobalt-containing catalyst synthesized in a subcritical water medium is investigated. It is determined that the resulting catalyst is characterized by a high specific surface area, and the cobalt-containing phase is represented by filamentous crystals of Co3O4 with a diameter of 10 nm and a length of 100-600 nm.
doi:10.34984/SCFTP.2022.17.3.003
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ГОСТ
7.0.100-2018
Structure of cobalt-containing particles stabilized in polymer synthesized in subcritical medium / – Текст : непосредственный // Сверхкритические Флюиды: Теория и Практика.. – 2022. – Т. 17. – № 3. – С. 19-25. - DOI:
TRANSLIT
Prevrashchenie pirrola v sverhkriticheskoj vode i struktura stabilizirovannyh v polimere kobal'tsoderzhashchih chastic, sintezirovannyh v subkriticheskoj vode flyuide / – Sverhkriticheskie Flyuidy: Teoriya i Praktika.. – 2022. – Т. 17. – № 3. – S. 19-25. - DOI:
En
Structure of cobalt-containing particles stabilized in polymer synthesized in subcritical medium. Sverhkriticheskie Flyuidy: Teoriya i Praktika, 3, 19-25 (2022). https://doi.org/
Key words: supercritical antisolvent deposition, crystallization, morphology, phase equilibria
The dependence of the size and morphology of levofloxacin hydrochloride particles (hereinafter referred to as levofloxacin) deposited by supercritical anti-solvent deposition (A) on the pressure and concentration of the micronized substance in solution is investigated. It is shown that the crystallization of levofloxacin from the two-phase CO2-acetone-levofloxacin system leads to the production of particles with a bimodal size distribution. An increase in pressure causes a change in the deposition regime, and as a consequence, the crystallization of smaller particles. Liquid-gas equilibrium curves for the CO2-acetone-levofloxacin system at a temperature of 40 °C were constructed for the first time.
doi:10.34984/ SCFTP.2022.17.3.004
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ГОСТ
7.0.100-2018
Micronization of levofloxacin hydrochloride by supercritical antisolvent deposition from single-phase and two-phase mixtures of CO2—acetone / – Текст : непосредственный // Сверхкритические Флюиды: Теория и Практика.. – 2022. – Т. 17. – № 3. – С. 26-36. - DOI:
TRANSLIT
Mikronizaciya gidrohlorida levofloksacina metodom sverhkriticheskogo antisol'ventnogo osazhdeniya iz odnofaznoj i dvuhfaznoj smesej co2—aceton / – Sverhkriticheskie Flyuidy: Teoriya i Praktika.. – 2022. – Т. 17. – № 3. – S. 26-36. - DOI:
En
Micronization of levofloxacin hydrochloride by supercritical antisolvent deposition from single-phase and two-phase mixtures of CO2—acetone. Sverhkriticheskie Flyuidy: Teoriya i Praktika, 3, 26-36 (2022). https://doi.org/
Key words: chitosan, lignosulfonate, alginate, aerogel, textural characteristics, supercritical fluid technologies, organic and carbon-native aerogels
Based on two—component hydrogels sodium alginate—chitosan (ALNa—HT) and sodium lignosulfonate—chitosan (LSNa-HT) with the use of supercritical fluid technologies and carbonation, organic and carbon aerogels were obtained. The effect of the solvent-acetone replacement regime in hydrogels on the textural properties of aerogels based on them has been studied. It is shown that the dynamic mode of solvent replacement in two-component hydrogels can reduce the duration of the process by six times and significantly reduce the consumption of acetone compared to the solvent replacement in static mode, as well as preserve the developed porous structure of the material. The specific surface area of organic ALNa-HT and LSNa-HT aerogels is 100 and 260 m2/g, and the carbon aerogels obtained from them are 438 and 868 m2/g, respectively. Scanning electron and atomic force microscopy methods have established that the supramolecular structure of synthesized organic and carbon aerogel nanomaterials is a cluster.
doi:10.34984/SCFTP.2022.17.3.005
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7.0.100-2018
The influence of the structure of biopolymers on the morphology of organic and carbon aerogel nanomaterials based on them / – Текст : непосредственный // Сверхкритические Флюиды: Теория и Практика.. – 2022. – Т. 17. – № 3. – С. 37-50. - DOI:
TRANSLIT
Vliyanie struktury biopolimerov na morfologiyu organicheskih i uglerodnyh / – Sverhkriticheskie Flyuidy: Teoriya i Praktika.. – 2022. – Т. 17. – № 3. – S. 37-50. - DOI:
En
The influence of the structure of biopolymers on the morphology of organic and carbon aerogel nanomaterials based on them. Sverhkriticheskie Flyuidy: Teoriya i Praktika, 3, 37-50 (2022). https://doi.org/
Key words: anisole, deoxygenation, supercritical hexane, aromatic hydrocarbons
The influence of temperature, pressure and composition of the gas phase on the process of deoxygenation of anisole in supercritical n-hexane in the presence of a palladium catalyst deposited on super-crosslinked polystyrene is investigated. The maximum yield of aromatic products (benzene and toluene) was obtained under the following conditions: temperature 270 °C, initial pressure of the nitrogen—hydrogen mixture (20 vol. % H2) 1.5 MPa.
doi:10.34984/SCFTP.2022.17.3.006
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ГОСТ
7.0.100-2018
Influence of conditions on the process of anisole deoxygenation in supercritical n-hexane in the presence of a palladium catalyst / – Текст : непосредственный // Сверхкритические Флюиды: Теория и Практика.. – 2022. – Т. 17. – № 3. – С. 51-59. - DOI:
TRANSLIT
Vliianie uslovii na protsess deoksigenatsii anizola v sverkhkriticheskom n-geksane v prisutstvii palladievogo katalizatora / – Sverhkriticheskie Flyuidy: Teoriya i Praktika.. – 2022. – Т. 17. – № 3. – S. 51-59. - DOI:
En
Influence of conditions on the process of anisole deoxygenation in supercritical n-hexane in the presence of a palladium catalyst. Sverhkriticheskie Flyuidy: Teoriya i Praktika, 3, 51-59 (2022). https://doi.org/
Key words: tetra-n-octylamide of diglycolic acid, supercritical fluid extraction, carbon dioxide, water, nitric acid, interphase equilibria
Data on the solubility of diglycolic acid tetran-n-octylamide (TODHA) in supercritical (SC) carbon dioxide at 310-360 K and a pressure of 80-250 bar were obtained. The influence of the presence of an aqueous phase containing nitric acid on the solubility of TODGA in SC-CO2 has been studied. It is shown that the equilibria in the TODGA—water—nitric acid—CO2 system depend in a complex way on the content of each component in it and the state parameters. The patterns characteristic of the TODGA—SC-CO2 dual system cannot be transferred to the four-component TODGA—water—nitric acid—CO2 system, since the presence of highly polar water and nitric acid in it has a critically strong effect on the transition of TODGA to the fluid phase, despite the very low solubility in the structure of these compounds.
doi:10.34984/SCFTP.2022.17.3.007
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ГОСТ
7.0.100-2018
Еquilibria in the system of tetra-n-octylamide of diglycolic acid—water—nitric acid— carbon dioxide / – Текст : непосредственный // Сверхкритические Флюиды: Теория и Практика.. – 2022. – Т. 17. – № 3. – С. 60-77. - DOI:
TRANSLIT
Ravnovesiia v sisteme tetra-n-oktilamid diglikolevoi kisloty voda azotnaia kislota dioksid ugleroda / – Sverhkriticheskie Flyuidy: Teoriya i Praktika.. – 2022. – Т. 17. – № 3. – S. 60-77. - DOI:
En
Еquilibria in the system of tetra-n-octylamide of diglycolic acid—water—nitric acid— carbon dioxide. Sverhkriticheskie Flyuidy: Teoriya i Praktika, 3, 60-77 (2022). https://doi.org/
Key words: decalin, carbon dioxide, phase equilibrium, solubility, thermodynamic model, Peng-Robinson equation
When studying the phase equilibrium of the decalin-carbon dioxide binary system carried out at isotherms 313 and 333 K and in the pressure range of 2-15 MPa using a high-pressure optical cell, type II phase behavior was established. The experimental results are described using the Peng-Robinson equation of state.
doi:10.34984/SCFTP.2022.17.3.008
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ГОСТ
7.0.100-2018
Phase equilibrium of the decalin—carbon dioxide binary system / – Текст : непосредственный // Сверхкритические Флюиды: Теория и Практика.. – 2022. – Т. 17. – № 3. – С. 78-87. - DOI:
TRANSLIT
Fazovoe ravnovesie binarnoj sistemy dekalin—dioksid ugleroda / – Sverhkriticheskie Flyuidy: Teoriya i Praktika.. – 2022. – Т. 17. – № 3. – S. 78-87. - DOI:
En
Phase equilibrium of the decalin—carbon dioxide binary system. Sverhkriticheskie Flyuidy: Teoriya i Praktika, 3, 78-87 (2022). https://doi.org/