Navegando por Assunto "Extraction with supercritical fluid"

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Acesso aberto (Open Access)
Modelagem e simulação de sistemas multicomponentes a altas pressões aplicada a separação de compostos bioativos
(Universidade Federal do Pará, 2014-04-30) SILVA, Welisson de Araújo; ARAÚJO, Marilena Emmi; http://lattes.cnpq.br/8983914018546682
Large applications using supercritical fluids related to the fractionation of natural products have been studied in recent decades. This work had as objective the thermodynamic modeling of phase equilibrium of binary and multicomponent systems of vegetable oils related compounds (fatty acids, triglycerides, squalene, α-tocopherol and methyl and ethyl esters of fatty acids) with supercritical carbon dioxide, using the cubic equations of state of Soave-Redich-Kwong (SRK) and Peng-Robinson (PR), with the Quadratic and Mathias-Klotz-Prausnitz mixing rules, to build a database of binary interaction parameters between these constituents and between these constituents with carbon dioxide, with an emphasis on the interactions related to bioactive compounds. The equations of PR and SRK showed efficiency in correlation of binary systems equilibrium data. For most binary systems experimental data fit, with the mixing rules with two binary interaction parameters, obtained good results and cash equivalents when compared with the mixing rules with three parameters. For multicomponent systems, when the experimental data were correlated with the PE program, employing both equations with quadratic mixing rule, shown convergence, best results for phase equilibrium description and the representativeness of the thermodynamic analysis of separation through the distribution coefficients were obtained. For the CO2 (1)/(2) oleic acid/linoleic acid (3) system, the prediction of equilibrium with an interaction parameters matrix of binary systems proved equivalent in relation to the use of multicomponent systems interaction parameters. In relation to the CO2 (1)/Methyl Myristate (2)/Methyl Palmitate (3) system the results obtained from the calculation using the interaction parameters matrix of binary systems, as with the parameters of interaction of multicomponent system, showed average deviation similar to the temperature of 323.15 K. For the CO2 (1)/Squalene (2)/(3)/Triolein oleic acid (4) system, the best results were obtained by the Quadratic mixing rule with the multi-component system interaction parameters. In relation to the CO2 (1)/(2) oleic acid/Palmitic acid (3)/Squalene (4) system, the results obtained using the interaction parameters matrix of binary systems showed average deviations below 8%. The calculation of the ELV for the CO2 (1)/Methyl Myristate (2)/Methyl Palmitate (3)/Methyl Oleate (4)/Methyl Stearate (5) system, with the EDEflash and PE program with Quadratic mixture rule, using the interaction parameters matrix from binary systems showed similar results. For the CO2 (1)/Ethyl Palmitate (2)/ Ethyl Stearate(3)/ Ethyl Oleate (4)/ Ethyl Linoleate (5) (palm oil ethyl esters) system, the prediction of the ELV with the SRK combined with Quadratic mixing rule, using the interaction parameters matrix from binary systems, presented results with deviations below 4% in both phases at 333.15 K.
Acesso aberto (Open Access)
Obtenção de gordura das sementes de Ucuúba (Virola surinamensis) por meio de extração com CO2 em estado supercrítico: rendimento global, dados cinéticos, ácidos graxos totais e atividade antimicrobiana
(Universidade Federal do Pará, 2015-09-28) CORDEIRO, Renato Macedo; CARVALHO JÚNIOR, Raul Nunes de; http://lattes.cnpq.br/5544305606838748
The Virola surinamensis, popularly known as ucuúba, is a typical tree found in floodplain habitats and along rivers in the Amazon region. The fat extracted from the seeds has a high melting point and is a product appreciated by the cosmetic industry. The objective of this work was to study the extraction of ucuúba seed fat using supercritical fluid and compare, in terms of process yield and composition of the extracts, with those obtained from the organic solvent extraction technique (via soxhlet). The extraction technique Supercritical Fluid Extraction (SFE) was used because it is regarded as a clean technology, economically attractive, and environmentally safe, avoiding the consumption of large amounts of organic solvents, which are often expensive and potentially harmful. The supercritical extracts of ucuúba seeds were obtained at temperatures of 40, 60 and 80 °C, combined with a pressure of 350 bar, the solvent density varied between 789.2 and 935.6 kg / m3, and a flow of 2.7 L / min. The highest yield obtained using supercritical CO2 was 64.39% for the extraction condition of 350 bar and 80 °C. The yield for the extraction via soxhlet was 61.38%. The mass transfer models of Goto et al. (1993), Esquivel et al. (1999), Tan and Lio (1989), Barton (1991) and Martinez et al. (2003) were employed to describe the extraction kinetics using supercritical fluid. The models that best described the extraction kinetics, with low average deviations, were the models of Martinez et al. (2003) and Goto et al. (1991). The fatty acid profile analysis showed that the ucuúba fat is composed predominantly of saturated fatty acids, mainly of myristic and lauric acids. The antimicrobial activity of the fats obtained was tested on the following organisms: Candida albicans, Staphylococcus aureus and Escherichia coli. Only the bacterium Staphylococcus aureus showed zone of inhibition, ranging from 10 to 11 mm.