Cosolvent
Mostrando 1-12 de 58 artigos, teses e dissertações.
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1. SUPERCRITICAL EXTRACTION OF LYOPHILIZED STRAWBERRY ANTHOCYANINS WITH PULSED ELECTRIC FIELDS PRETREATMENT
The lyophilized strawberry anthocyanins were extracted using a supercritical extraction (SE) process. The effect of pulsed electric fields (PEF) as pretreatment and the influence of the addition of ethanol as a cosolvent on the percentage of extraction yield (EY) and the total anthocyanin concentration (TAC) were analyzed. The effect of PEF was evaluated at
Química Nova. Publicado em: 2022
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2. Appliance of a high pressure semi-batch reactor: supercritical transesterification of soybean oil using methanol
Abstract This work presents the results of a supercritical transesterification process of soybean oil using methanol, performed in a laboratory high pressure semi-batch reactor. A full description of the equipment and a standard operating procedure are also provided. Since fossil fuels are not renewable, biofuels such biodiesel, have gained attention over t
Food Sci. Technol. Publicado em: 31/01/2019
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3. Effect of Acetonitrile and N,N-Dimethylformamide on the Formation of Poly(ethylene oxide)-Sodium Alkyl Sulfate Aggregates
The effects of low contents of acetonitrile (AN) or N,N-dimethylformamide (DMF) on the aggregation of sodium alkyl sulfate surfactants, in the absence and presence of poly(ethylene oxide) (PEO), were investigated using conductivity and isothermal titration calorimetry. The cosolvents slightly changed the critical micellar concentrations and did not alter the
J. Braz. Chem. Soc.. Publicado em: 2018-01
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4. Perspectives on the integration of a supercritical fluid extraction plant to a sugarcane biorefinery: thermo-economical evaluation of CO2 recycle systems
Abstract In the present study, the software Aspen Plus® was used to analyse two different systems for CO2 recycle in a SFE process for extraction of more polar compounds using ethanol as co-solvent, the most common co-solvent used due to its environment-friendly nature. The extraction process of β-ecdysone from Brazilian ginseng roots was considered as exa
Food Sci. Technol. Publicado em: 08/05/2017
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5. Effect of Polyethyleneglycols (PEG) on Solubility of CoIII5,10,15,20-Tetra(4-carboxyphenyl)porphyrin and Methylimidazolyl Axial Complex at 298.2 K: Experiment and Modeling
The solubility of CoIII 5,10,15,20-tetra(4-carboxyphenyl)porphyrin and axial complex with methylimidazole in the mixtures of triethyleneglycol-water and tetraethyleneglycol-water was measured in the whole range of polyethyleneglycols (PEG) fractions at 298.2 K using the isothermal saturation method. The composition of the mixture at which the maximal solubil
J. Braz. Chem. Soc.. Publicado em: 2016-03
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6. Laccase produced by a thermotolerant strain of Trametes trogii LK13
Thermophilic and thermotolerant micro-organisms strains have served as the natural source of industrially relevant and thermostable enzymes. Although some strains of the Trametes genus are thermotolerant, few Trametes strains were studied at the temperature above 30 °C until now. In this paper, the laccase activity and the mycelial growth rate for Trametes
Braz. J. Microbiol.. Publicado em: 2015-03
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7. Continuous catalyst-free production of esters from Jatropha curcas L. oil under supercritical ethanol
In the present study, the transesterification of Jatropha oil in a continuous catalyst-free process using supercritical ethanol was investigated. Experiments were performed in a packed-bed tubular reactor by studying the effect on the reaction of temperature, pressure, water and cosolvent (n-hexane) concentrations, keeping the oil:ethanol mass ratio fixed at
Braz. J. Chem. Eng.. Publicado em: 2014-09
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8. Supercritical CO2 extraction of raw propolis and its dry ethanolic extract
Three types of propolis extract were prepared and analyzed with respect to their global extraction yields and with respect to the concentration of the following markers: 3,5-diprenyl-4-hydroxycinnamic acid; 3-prenyl-4-hydroxycinnamic acid; 4-hydroxycinnamic acid and 4-methoxy-3,5,7-trihydroxyflavone. The extract EEP (ethanolic extract of propolis) was obtain
Brazilian Journal of Chemical Engineering. Publicado em: 2012-06
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9. Extraction, fatty acid profile and antioxidant activity of sesame extract (Sesamum Indicum L.)
This article carried out the extraction of sesame oil by using three extraction techniques: supercritical fluid extraction (SFE), Soxhlet and sequential extraction. The SFE was performed using supercritical carbon dioxide (SC-CO2) as solvent and ethanol as cosolvent. Tests were performed at 20 MPa, 35ºC and a flow rate of 2.5 g CO2/min with a total extracti
Brazilian Journal of Chemical Engineering. Publicado em: 2012-06
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10. Método extendido de Hildebrand en la predicción de la solubilidad del ketoprofeno en mezclas cosolventes etanol + agua
Extended Hildebrand Solubility Approach (EHSA) developed by Martin et al. was applied to evaluate the solubility of ketoprofen (KTP) in ethanol + water cosolvent mixtures at 298.15 K. Calculated values of molar volume and solubility parameter for KTP were used. A good predictive capacity of EHSA was found by using a regular polynomial model in order five to
Química Nova. Publicado em: 2010
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11. Thermodynamic study of the solubility of sodium naproxen in some ethanol + water mixtures
By using the van't Hoff and Gibbs equations the apparent thermodynamic functions Gibbs energy, enthalpy, and entropy of solution for sodium naproxen in ethanol + water cosolvent mixtures, were evaluated from solubility data determined at temperatures from (278.15 to 308.15) K. The drug solubility was greatest in neat water and lowest in neat ethanol at all t
Química Nova. Publicado em: 2010
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12. Extração supercritica de astaxantina e lipideos ricos em acidos graxos omega -3 a partir de residuos de camarão-rosa (Farfantepenaeus paulensis) / Supercritical extraction of astaxanthin and lipids with high content of omega -3 from brazilian redspotted shrimp waste (Farfantepenaeus paulensis)
O rendimento de processamento e a composição centesimal dos resíduos de camarão-rosa (Farfantepenaeus paulensis) foram investigados. Os resultados indicaram que nos resíduos de camarão (cabeça, casca e caudas liofilizadas) apresenta-se um alto conteúdo protéico (48,8% b.s.) e um alto nível de resíduo mineral (27,0% b.s.). Os resíduos de camarão
Publicado em: 2010