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Equilibrium studies on enantioselective liquid-liquid Amino Acid extraction using a cinchona alkaloid extractant / Boelo Schuur ; Jozef G.M. Winkelman ; Hero J. Heeres in Industrial & engineering chemistry research, Vol. 47 n°24 (Décembre 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 n°24 (Décembre 2008) . - p. 10027–10033 Titre : Equilibrium studies on enantioselective liquid-liquid Amino Acid extraction using a cinchona alkaloid extractant Type de document : texte imprimé Auteurs : Boelo Schuur, Auteur ; Jozef G.M. Winkelman, Auteur ; Hero J. Heeres, Auteur Année de publication : 2009 Article en page(s) : p. 10027–10033 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Liquid-Liquid  Amino  Acid Résumé : The enantioselective extraction of aqueous 3,5-dinitrobenzoyl-R,S-leucine (AR,S) by a cinchona alkaloid extractant (C) in 1,2-dichloroethane was studied at room temperature (294 K) in a batch system for a range of intake concentrations (10−4−10−3 mol/L) and pH values (3.8−6.6). The experimental data were described by a reactive extraction model with a homogeneous organic phase reaction of AR,S with C. Important parameters of this model were determined experimentally. The acid dissociation constant, Ka, of AR,S was (1.92 ± 0.07) × 10−4 mol/L. The physical distribution coefficient of AR,S between the organic and aqueous phase was 8.04 ± 0.39. The equilibrium constants of the organic phase complexation reaction were (9.31 ± 0.76) × 104 L/mol and (2.71 ± 0.76) × 104 L/mol for the S- and R-enantiomers, respectively. With these parameters an optimum performance factor, PF, of 0.19 was predicted. The PF was independent of the pH provided that pH ≫ pKa. The model was verified experimentally with excellent results (±7.9%). En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800668e [article] Equilibrium studies on enantioselective liquid-liquid Amino Acid extraction using a cinchona alkaloid extractant [texte imprimé] / Boelo Schuur, Auteur ; Jozef G.M. Winkelman, Auteur ; Hero J. Heeres, Auteur . - 2009 . - p. 10027–10033. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 n°24 (Décembre 2008) . - p. 10027–10033 Mots-clés : Liquid-Liquid  Amino  Acid Résumé : The enantioselective extraction of aqueous 3,5-dinitrobenzoyl-R,S-leucine (AR,S) by a cinchona alkaloid extractant (C) in 1,2-dichloroethane was studied at room temperature (294 K) in a batch system for a range of intake concentrations (10−4−10−3 mol/L) and pH values (3.8−6.6). The experimental data were described by a reactive extraction model with a homogeneous organic phase reaction of AR,S with C. Important parameters of this model were determined experimentally. The acid dissociation constant, Ka, of AR,S was (1.92 ± 0.07) × 10−4 mol/L. The physical distribution coefficient of AR,S between the organic and aqueous phase was 8.04 ± 0.39. The equilibrium constants of the organic phase complexation reaction were (9.31 ± 0.76) × 104 L/mol and (2.71 ± 0.76) × 104 L/mol for the S- and R-enantiomers, respectively. With these parameters an optimum performance factor, PF, of 0.19 was predicted. The PF was independent of the pH provided that pH ≫ pKa. The model was verified experimentally with excellent results (±7.9%). En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800668e