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Solvent effect in homogeneous and heterogeneous reactions to remove dibenzothiophene by an oxidation-extraction scheme / Luis F. Ramirez-Verduzco in Industrial & engineering chemistry research, Vol. 47 n°15 (Août 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 n°15 (Août 2008) . - p. 5353–5361 Titre : Solvent effect in homogeneous and heterogeneous reactions to remove dibenzothiophene by an oxidation-extraction scheme Type de document : texte imprimé Auteurs : Luis F. Ramirez-Verduzco, Auteur ; J. A. De los Reyes, Auteur ; E. Torres-Garcia, Auteur Année de publication : 2008 Article en page(s) : p. 5353–5361 Note générale : Bibliogr. p. 5360-5361 Langues : Anglais (eng) Mots-clés : Dibenzothiophene  --  oxidation−extraction  scheme;  Heterogeneous  reactions;  Homogeneous  reactions Résumé : In this work a study of dibenzothiophene removal by an oxidation−extraction scheme is presented. Experiments were carried out to observe the role that the solvent plays during the process, as well as the oxidizing agent and catalyst. The oxidation was carried out with hydrogen peroxide in the presence of a catalyst of tungsten supported on zirconia (WOx−ZrO2). A dibenzothiophene + n-hexadecane model mixture was employed to simulate a diesel fuel. Methanol, ethanol, acetonitrile, and γ-butyrolactone were used as extraction solvents. Dibenzothiophene (DBT) was removed more efficiently by γ-butyrolactone with respect to other solvents. The highest reactivity was achieved when γ-butyrolactone was used during DBT oxidation with and without catalyst. When oxidation was carried out without catalyst, the oxidant behavior of the mixture could be explained in terms of the dissociation of hydrogen peroxide to produce strong oxidant species such as perhydroxyl ions (HO2−) by the influence of the aprotic solvents. Finally, when a catalyst was used during the oxidation, there was an additional oxidation contribution through the formation of surface peroxo−metal intermediates (W−O−O−H). En ligne : http://pubs.acs.org/doi/abs/10.1021/ie701692r [article] Solvent effect in homogeneous and heterogeneous reactions to remove dibenzothiophene by an oxidation-extraction scheme [texte imprimé] / Luis F. Ramirez-Verduzco, Auteur ; J. A. De los Reyes, Auteur ; E. Torres-Garcia, Auteur . - 2008 . - p. 5353–5361. Bibliogr. p. 5360-5361 Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 n°15 (Août 2008) . - p. 5353–5361 Mots-clés : Dibenzothiophene  --  oxidation−extraction  scheme;  Heterogeneous  reactions;  Homogeneous  reactions Résumé : In this work a study of dibenzothiophene removal by an oxidation−extraction scheme is presented. Experiments were carried out to observe the role that the solvent plays during the process, as well as the oxidizing agent and catalyst. The oxidation was carried out with hydrogen peroxide in the presence of a catalyst of tungsten supported on zirconia (WOx−ZrO2). A dibenzothiophene + n-hexadecane model mixture was employed to simulate a diesel fuel. Methanol, ethanol, acetonitrile, and γ-butyrolactone were used as extraction solvents. Dibenzothiophene (DBT) was removed more efficiently by γ-butyrolactone with respect to other solvents. The highest reactivity was achieved when γ-butyrolactone was used during DBT oxidation with and without catalyst. When oxidation was carried out without catalyst, the oxidant behavior of the mixture could be explained in terms of the dissociation of hydrogen peroxide to produce strong oxidant species such as perhydroxyl ions (HO2−) by the influence of the aprotic solvents. Finally, when a catalyst was used during the oxidation, there was an additional oxidation contribution through the formation of surface peroxo−metal intermediates (W−O−O−H). En ligne : http://pubs.acs.org/doi/abs/10.1021/ie701692r