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Modeling of effect of pH on mass transfer of copper(II) extraction by hollow fiber renewal liquid membrane / Zhongqi Ren in Industrial & engineering chemistry research, Vol. 47 n°12 (Juin 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 n°12 (Juin 2008) . - p. 4256–4262 Titre : Modeling of effect of pH on mass transfer of copper(II) extraction by hollow fiber renewal liquid membrane Type de document : texte imprimé Auteurs : Zhongqi Ren, Auteur ; Zhang, Weidong, Auteur ; Yuan Dai, Auteur ; Yanqiang Yang, Auteur Année de publication : 2008 Article en page(s) : p. 4256–4262 Note générale : Bibliogr. p. 4262 Langues : Anglais (eng) Mots-clés : Copper  extraction;  PH  --  Mass  transfer;  Acetate  ion Résumé : In this paper, the effects of pH on the mass transfer of copper extraction with hollow fiber renewal liquid membrane (HFRLM), which is a new type of liquid membrane system based on the surface renewal theory, were investigated. The system of CuSO4 in acetate buffer solution + D2EHPA in kerosene + acidic aqueous solutions was used to study the effects of pH and acetate ion concentration in the feed phase and type and acidity of the stripping phase on the mass transfer performance of the HFRLM process. Results showed that the mass transfer flux and removal efficiency of copper increase with increasing pH in the feed phase, reach a maximum value at pH of 4.44, and then decrease; an addition of acetate buffer solution at a low acetate ion concentration in the feed phase is enough for maintaining the higher mass transfer flux and removal efficiency in the HFRLM process. The influence of the stripping phase on the mass transfer performance of the HFRLM process is weak in our ranges studied. The stripping phase at a low hydrogen concentration is enough for the extraction of copper by HFRLM. The mass transfer fluxes of copper ions from feed solutions with different stripping acids followed the order: Cl− > PO43− > SO42− > NO3−. And, a detailed mathematical model was developed based on the surface renewal theory. The calculated results have good agreement with experimental results. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie0714798 [article] Modeling of effect of pH on mass transfer of copper(II) extraction by hollow fiber renewal liquid membrane [texte imprimé] / Zhongqi Ren, Auteur ; Zhang, Weidong, Auteur ; Yuan Dai, Auteur ; Yanqiang Yang, Auteur . - 2008 . - p. 4256–4262. Bibliogr. p. 4262 Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 n°12 (Juin 2008) . - p. 4256–4262 Mots-clés : Copper  extraction;  PH  --  Mass  transfer;  Acetate  ion Résumé : In this paper, the effects of pH on the mass transfer of copper extraction with hollow fiber renewal liquid membrane (HFRLM), which is a new type of liquid membrane system based on the surface renewal theory, were investigated. The system of CuSO4 in acetate buffer solution + D2EHPA in kerosene + acidic aqueous solutions was used to study the effects of pH and acetate ion concentration in the feed phase and type and acidity of the stripping phase on the mass transfer performance of the HFRLM process. Results showed that the mass transfer flux and removal efficiency of copper increase with increasing pH in the feed phase, reach a maximum value at pH of 4.44, and then decrease; an addition of acetate buffer solution at a low acetate ion concentration in the feed phase is enough for maintaining the higher mass transfer flux and removal efficiency in the HFRLM process. The influence of the stripping phase on the mass transfer performance of the HFRLM process is weak in our ranges studied. The stripping phase at a low hydrogen concentration is enough for the extraction of copper by HFRLM. The mass transfer fluxes of copper ions from feed solutions with different stripping acids followed the order: Cl− > PO43− > SO42− > NO3−. And, a detailed mathematical model was developed based on the surface renewal theory. The calculated results have good agreement with experimental results. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie0714798

The separation and concentration of Cr(VI) from acidic dilute solution using hollow fiber renewal liquid membrane / Junteng Liu in Industrial & engineering chemistry research, Vol. 48 N° 9 (Mai 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 9 (Mai 2009) . - pp. 4500–4506 Titre : The separation and concentration of Cr(VI) from acidic dilute solution using hollow fiber renewal liquid membrane Type de document : texte imprimé Auteurs : Junteng Liu, Auteur ; Zhang, Weidong, Auteur ; Zhongqi Ren, Auteur Année de publication : 2009 Article en page(s) : pp. 4500–4506 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Hollow  fiber  HFRLM  technique  Cr(VI)  Acidic  dilute  solution  Tri-n-butyl  phosphate Résumé : Hollow fiber renewal liquid membrane (HFRLM) technique for simultaneous separation and concentration of Cr(VI) from acidic dilute solution has been studied using tri-n-butyl phosphate as mobile carrier. The influences of the mobile carrier concentration, pH of the feed phase, the initial Cr(VI) concentration, and the stripping concentration on the mass transfer rate are investigated. The transport rate of Cr(VI) increases with increasing the carrier concentration and the stripping concentration, then reaches a “plateau”. The concentration factor as high as 25∼30 has been achieved easily. A mathematical model is proposed to explain the transport mechanism. The validity of this model is evaluated and good agreement between predicted results and experiment data are obtained. Results suggest that the HFRLM technique provides a promising alternative to treat industrial wastewater at low Cr(VI) concentration. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8017669 [article] The separation and concentration of Cr(VI) from acidic dilute solution using hollow fiber renewal liquid membrane [texte imprimé] / Junteng Liu, Auteur ; Zhang, Weidong, Auteur ; Zhongqi Ren, Auteur . - 2009 . - pp. 4500–4506. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 9 (Mai 2009) . - pp. 4500–4506 Mots-clés : Hollow  fiber  HFRLM  technique  Cr(VI)  Acidic  dilute  solution  Tri-n-butyl  phosphate Résumé : Hollow fiber renewal liquid membrane (HFRLM) technique for simultaneous separation and concentration of Cr(VI) from acidic dilute solution has been studied using tri-n-butyl phosphate as mobile carrier. The influences of the mobile carrier concentration, pH of the feed phase, the initial Cr(VI) concentration, and the stripping concentration on the mass transfer rate are investigated. The transport rate of Cr(VI) increases with increasing the carrier concentration and the stripping concentration, then reaches a “plateau”. The concentration factor as high as 25∼30 has been achieved easily. A mathematical model is proposed to explain the transport mechanism. The validity of this model is evaluated and good agreement between predicted results and experiment data are obtained. Results suggest that the HFRLM technique provides a promising alternative to treat industrial wastewater at low Cr(VI) concentration. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8017669