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Optimization, kinetics, and thermodynamics in the extraction process of puerarin by decompressing inner ebullition / Xiaoguang Chen in Industrial & engineering chemistry research, Vol. 51 N° 19 (Mai 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 19 (Mai 2012) . - pp. 6841–6846 Titre : Optimization, kinetics, and thermodynamics in the extraction process of puerarin by decompressing inner ebullition Type de document : texte imprimé Auteurs : Xiaoguang Chen, Auteur ; Tengyou Wei, Auteur ; Mengwei Peng, Auteur Année de publication : 2012 Article en page(s) : pp. 6841–6846 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Kinetics  Thermodynamics Résumé : Decompressing inner ebullition (DIE) is a novel method and it can achieve a rapid extraction at lower temperature for active constituents of medical plants. In this work, DIE was employed to extract puerarin from puerarin lobata (Willd.) Ohwi (PLO). The extraction conditions were investigated according single factor analysis. Experiment results showed that the extraction yield of puerarin reached a maximum value when the ethanol mass concentration in the aqueous solution immersing the PLO was 60%, the amount of ethanol solution for premaceration and of water for extraction were 1.6 and 10 mL·g–1 of PLO, respectively, the operation gauge pressure was −0.084 MPa, and the extraction temperature was 50 °C. Under the optimal conditions, the extraction kinetics of DIE was studied. The mass transfer coefficient of DIE ranged between 0.09 and 0.13 s–1, which is 183 times greater than that of ultrasonic assistant extraction under the same conditions, and its extraction activation energy ΔE is 10.86 kJ·mol–1. Also, the thermodynamics properties in the extraction process of DIE at 50 °C were also calculated, the enthalpy change ΔH is 58.76 kJ·mol–1, the entropy change ΔS is 224.50 J·mol–1·K–1, and Gibbs free energy ΔG is −13.73 kJ·mol–1, respectively. The extraction of DIE belongs to a spontaneous process with endothermic and entropy increasing. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2020153 [article] Optimization, kinetics, and thermodynamics in the extraction process of puerarin by decompressing inner ebullition [texte imprimé] / Xiaoguang Chen, Auteur ; Tengyou Wei, Auteur ; Mengwei Peng, Auteur . - 2012 . - pp. 6841–6846. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 19 (Mai 2012) . - pp. 6841–6846 Mots-clés : Kinetics  Thermodynamics Résumé : Decompressing inner ebullition (DIE) is a novel method and it can achieve a rapid extraction at lower temperature for active constituents of medical plants. In this work, DIE was employed to extract puerarin from puerarin lobata (Willd.) Ohwi (PLO). The extraction conditions were investigated according single factor analysis. Experiment results showed that the extraction yield of puerarin reached a maximum value when the ethanol mass concentration in the aqueous solution immersing the PLO was 60%, the amount of ethanol solution for premaceration and of water for extraction were 1.6 and 10 mL·g–1 of PLO, respectively, the operation gauge pressure was −0.084 MPa, and the extraction temperature was 50 °C. Under the optimal conditions, the extraction kinetics of DIE was studied. The mass transfer coefficient of DIE ranged between 0.09 and 0.13 s–1, which is 183 times greater than that of ultrasonic assistant extraction under the same conditions, and its extraction activation energy ΔE is 10.86 kJ·mol–1. Also, the thermodynamics properties in the extraction process of DIE at 50 °C were also calculated, the enthalpy change ΔH is 58.76 kJ·mol–1, the entropy change ΔS is 224.50 J·mol–1·K–1, and Gibbs free energy ΔG is −13.73 kJ·mol–1, respectively. The extraction of DIE belongs to a spontaneous process with endothermic and entropy increasing. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2020153