Documents disponibles écrits par cet auteur

Fe2+ - Catalyzed wet oxidation of phenolic acids under different pH values / Sergio Collado in Industrial & engineering chemistry research, Vol. 49 N° 24 (Décembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 24 (Décembre 2010) . - pp. 12405–12413 Titre : Fe2+ - Catalyzed wet oxidation of phenolic acids under different pH values Type de document : texte imprimé Auteurs : Sergio Collado, Auteur ; David Quero, Auteur ; Adriana Laca, Auteur Année de publication : 2011 Article en page(s) : pp. 12405–12413 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Catalytic  oxidation  Aqueous  phase Résumé : Catalytic oxidation in the aqueous phase of phenol and phenol-derivates present in pharmaceutical wastewaters has been investigated using FeSO4·7H2O as a homogeneous catalyst at 413 K and 1.0 MPa. Different initial pH values and catalyst concentrations have been tested, and the results obtained have been discussed taking into account the different roles that the iron plays depending on the pH value and the phenolic compound studied. The degradation rate of each pollutant assayed and the degree of mineralization achieved during the wet oxidation process were greatly affected by pH. The catalytic effect of iron(II) during the wet oxidation of phenol was only observed at pH values ranging between 2 and 3, due to the establishment of a Fe(III)/Fe(II) redox cycle. However, the best results for the catalytic oxidation of salicylic acid were obtained for pH values below 2, and they were related to the formation of an Fe(II)−salicylic acid complex. On the other hand, the presence of iron(II) had a prejudicial effect on the degradation of p-hydroxybenzoic and 5-hydroxyisophthalic acids, provoking the apparition of induction periods in both cases, due to the competition between the autoxidation of Fe(II) and the hydroxylation of the phenolic compound by the initial OH•. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101497s [article] Fe2+ - Catalyzed wet oxidation of phenolic acids under different pH values [texte imprimé] / Sergio Collado, Auteur ; David Quero, Auteur ; Adriana Laca, Auteur . - 2011 . - pp. 12405–12413. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 24 (Décembre 2010) . - pp. 12405–12413 Mots-clés : Catalytic  oxidation  Aqueous  phase Résumé : Catalytic oxidation in the aqueous phase of phenol and phenol-derivates present in pharmaceutical wastewaters has been investigated using FeSO4·7H2O as a homogeneous catalyst at 413 K and 1.0 MPa. Different initial pH values and catalyst concentrations have been tested, and the results obtained have been discussed taking into account the different roles that the iron plays depending on the pH value and the phenolic compound studied. The degradation rate of each pollutant assayed and the degree of mineralization achieved during the wet oxidation process were greatly affected by pH. The catalytic effect of iron(II) during the wet oxidation of phenol was only observed at pH values ranging between 2 and 3, due to the establishment of a Fe(III)/Fe(II) redox cycle. However, the best results for the catalytic oxidation of salicylic acid were obtained for pH values below 2, and they were related to the formation of an Fe(II)−salicylic acid complex. On the other hand, the presence of iron(II) had a prejudicial effect on the degradation of p-hydroxybenzoic and 5-hydroxyisophthalic acids, provoking the apparition of induction periods in both cases, due to the competition between the autoxidation of Fe(II) and the hydroxylation of the phenolic compound by the initial OH•. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101497s

Wet oxidation of thiocyanate under different pH conditions / Sergio Collado in Industrial & engineering chemistry research, Vol. 48 N° 22 (Novembre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 22 (Novembre 2009) . - pp. 9902–9909 Titre : Wet oxidation of thiocyanate under different pH conditions : kinetics and mechanistic analysis Type de document : texte imprimé Auteurs : Sergio Collado, Auteur ; Adriana Laca, Auteur ; Mario Díaz, Auteur Année de publication : 2010 Article en page(s) : pp. 9902–9909 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Thiocyanate  Wet  oxidation Résumé : The wet oxidation of thiocyanate has been investigated in a 1-L semibatch reactor at temperatures in the range of 438.15−468.15 K and total pressures between 2.0 × 103 kPa and 8.1 × 103 kPa. The initial pH value of the reaction media was varied between pH 2 and pH 12 and was found to be a key parameter in the rate of thiocyanate degradation. The evolution of concentration of substrate and products (sulfate and ammonium) were analyzed. Based on the experimental data and bibliography information, a kinetic model was obtained and, here, possible pathways, depending on the initial pH of the media, are suggested for thiocyanate oxidation. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9006485 [article] Wet oxidation of thiocyanate under different pH conditions : kinetics and mechanistic analysis [texte imprimé] / Sergio Collado, Auteur ; Adriana Laca, Auteur ; Mario Díaz, Auteur . - 2010 . - pp. 9902–9909. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 22 (Novembre 2009) . - pp. 9902–9909 Mots-clés : Thiocyanate  Wet  oxidation Résumé : The wet oxidation of thiocyanate has been investigated in a 1-L semibatch reactor at temperatures in the range of 438.15−468.15 K and total pressures between 2.0 × 103 kPa and 8.1 × 103 kPa. The initial pH value of the reaction media was varied between pH 2 and pH 12 and was found to be a key parameter in the rate of thiocyanate degradation. The evolution of concentration of substrate and products (sulfate and ammonium) were analyzed. Based on the experimental data and bibliography information, a kinetic model was obtained and, here, possible pathways, depending on the initial pH of the media, are suggested for thiocyanate oxidation. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9006485