Documents disponibles écrits par cet auteur

Equilibrium distribution model of betaine between surfactant micelles and water / Maria O. Ruiz in Industrial & engineering chemistry research, Vol. 49 N° 14 (Juillet 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 14 (Juillet 2010) . - pp. 6578–6586 Titre : Equilibrium distribution model of betaine between surfactant micelles and water : application to a micellar - enhanced ultrafiltration process Type de document : texte imprimé Auteurs : Maria O. Ruiz, Auteur ; José M. Benito, Auteur ; Beatriz Barriuso, Auteur Année de publication : 2010 Article en page(s) : pp. 6578–6586 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Ultrafiltration  process Résumé : The aim of this work was to determine the optimal surfactant concentration and operating conditions for betaine recovery from aqueous solutions by micellar-enhanced ultrafiltration (MEUF). Initial centrifugal ultrafiltration experiments with commercial 5 kDa cutoff polyethersulfone membranes showed that optimal betaine extraction was achieved with 200 mol/m3 of sodium dodecyl sulfate (SDS) as surfactant, at pH 1, with phosphoric acid for pH adjustment. The degree of betaine extraction increased with SDS concentration but remained constant with increasing betaine concentration for a given initial SDS concentration. The equilibrium distribution constants, KS, of betaine between SDS micelles and water were determined assuming a theoretical pseudophase separation model. Continuous MEUF with a 5 kDa cutoff TiO2 tubular ceramic membrane was performed in order to concentrate the micellar solution. Complete rejection of the micelles by the membrane was observed, resulting in 54% of the betaine and 99% of the SDS in micellar form, in agreement with the values estimated using the proposed theoretical model. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100485w [article] Equilibrium distribution model of betaine between surfactant micelles and water : application to a micellar - enhanced ultrafiltration process [texte imprimé] / Maria O. Ruiz, Auteur ; José M. Benito, Auteur ; Beatriz Barriuso, Auteur . - 2010 . - pp. 6578–6586. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 14 (Juillet 2010) . - pp. 6578–6586 Mots-clés : Ultrafiltration  process Résumé : The aim of this work was to determine the optimal surfactant concentration and operating conditions for betaine recovery from aqueous solutions by micellar-enhanced ultrafiltration (MEUF). Initial centrifugal ultrafiltration experiments with commercial 5 kDa cutoff polyethersulfone membranes showed that optimal betaine extraction was achieved with 200 mol/m3 of sodium dodecyl sulfate (SDS) as surfactant, at pH 1, with phosphoric acid for pH adjustment. The degree of betaine extraction increased with SDS concentration but remained constant with increasing betaine concentration for a given initial SDS concentration. The equilibrium distribution constants, KS, of betaine between SDS micelles and water were determined assuming a theoretical pseudophase separation model. Continuous MEUF with a 5 kDa cutoff TiO2 tubular ceramic membrane was performed in order to concentrate the micellar solution. Complete rejection of the micelles by the membrane was observed, resulting in 54% of the betaine and 99% of the SDS in micellar form, in agreement with the values estimated using the proposed theoretical model. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100485w

Vacuum evaporation of waste oil-in-water emulsions from a copper metalworking industry / Gemma Gutiérrez in Industrial & engineering chemistry research, Vol. 48 N°4 (Février 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N°4 (Février 2009) . - p. 2100–2106 Titre : Vacuum evaporation of waste oil-in-water emulsions from a copper metalworking industry Type de document : texte imprimé Auteurs : Gemma Gutiérrez, Auteur ; José M. Benito, Auteur ; José Coca, Auteur Année de publication : 2009 Article en page(s) : p. 2100–2106 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Vacuum  evaporation  Waste  oil-in-water  Copper  metalworking  industry Résumé : The performance of vacuum evaporation was evaluated for the treatment of waste oil-in-water (O/W) emulsions, one synthetic (Multiroll) and two semisynthetic (Unopol and Divinol), used in a copper metalworking industry. A destabilization/settling pretreatment step using Nalco 71243 (NAL, a quaternary polyamine) as flocculant and CaCl2 and AlCl3·6H2O as coagulants was also investigated. The quality of the final aqueous effluent was evaluated in terms of chemical oxygen demand (COD), turbidity, conductivity, and biological oxygen demand (BOD5). COD reduction greater than 99% was achieved. The pretreatment step did not significantly improve either the evaporation rate or the quality of the condensate. Moreover, evaporation of a totally exhausted Unopol waste emulsion carried out in an industrial falling film evaporator showed good agreement with results obtained at the laboratory scale. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801054d [article] Vacuum evaporation of waste oil-in-water emulsions from a copper metalworking industry [texte imprimé] / Gemma Gutiérrez, Auteur ; José M. Benito, Auteur ; José Coca, Auteur . - 2009 . - p. 2100–2106. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N°4 (Février 2009) . - p. 2100–2106 Mots-clés : Vacuum  evaporation  Waste  oil-in-water  Copper  metalworking  industry Résumé : The performance of vacuum evaporation was evaluated for the treatment of waste oil-in-water (O/W) emulsions, one synthetic (Multiroll) and two semisynthetic (Unopol and Divinol), used in a copper metalworking industry. A destabilization/settling pretreatment step using Nalco 71243 (NAL, a quaternary polyamine) as flocculant and CaCl2 and AlCl3·6H2O as coagulants was also investigated. The quality of the final aqueous effluent was evaluated in terms of chemical oxygen demand (COD), turbidity, conductivity, and biological oxygen demand (BOD5). COD reduction greater than 99% was achieved. The pretreatment step did not significantly improve either the evaporation rate or the quality of the condensate. Moreover, evaporation of a totally exhausted Unopol waste emulsion carried out in an industrial falling film evaporator showed good agreement with results obtained at the laboratory scale. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801054d