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Cu - Zn - (Mn) - (Fe) - al layered double hydroxides and their mixed metal oxides / L. H. Zhang in Industrial & engineering chemistry research, Vol. 49 N° 13 (Juillet 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 13 (Juillet 2010) . - pp. 5959–5968 Titre : Cu - Zn - (Mn) - (Fe) - al layered double hydroxides and their mixed metal oxides : physicochemical and catalytic properties in wet hydrogen peroxide oxidation of phenol Type de document : texte imprimé Auteurs : L. H. Zhang, Auteur ; F. Li, Auteur ; D. G. Evans, Auteur Année de publication : 2010 Article en page(s) : pp. 5959–5968 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Oxidation  Hydrogen  peroxide  Catalytic  reaction Résumé : Cu−Zn−Mn−Fe−Al layered double hydroxides (LDHs) with Cu/Zn/Mn/Fe/Al atomic ratios of 1/1/0/0/1, 1/1/1/0.3/0.7, and 1/0.7/0.3/0.3/0.7, respectively, in synthesis mixture were prepared by coprecipitation under controlled conditions of temperature and pH. The mixed oxides were obtained by decomposition of the precursors at 500 °C in air. The characterization has been performed by XRD, ICP-ES, FT-IR, TG−DTA, TG−DTA−MS, TEM, XPS,O2-TPD, and H2-TPR. The objective is to investigate the effects of Mn and Fe partial substitution into Cu−Zn−Al mixed metal oxide derived from LDH precursor on the physicochemical and catalytic properties. The results show that the Fe and Mn substitutions decrease the structural stability of LDHs and improve the redox behavior of calcined LDHs. The activity of catalytic wet hydrogen peroxide oxidation of phenol is proportional to the content of surface metal ions and mainly Cu2+ centers linked to the surface lattice oxygen, and the degree of the deep oxidation of it is mainly related to the reactivity of the weakly bonded surface oxygen, depending on the nature of the transition metal ions in the structure. The preoxidation of phenol by surface •OH radical originating from hydrogen peroxide favors the next deep oxidation. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=22974410 [article] Cu - Zn - (Mn) - (Fe) - al layered double hydroxides and their mixed metal oxides : physicochemical and catalytic properties in wet hydrogen peroxide oxidation of phenol [texte imprimé] / L. H. Zhang, Auteur ; F. Li, Auteur ; D. G. Evans, Auteur . - 2010 . - pp. 5959–5968. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 13 (Juillet 2010) . - pp. 5959–5968 Mots-clés : Oxidation  Hydrogen  peroxide  Catalytic  reaction Résumé : Cu−Zn−Mn−Fe−Al layered double hydroxides (LDHs) with Cu/Zn/Mn/Fe/Al atomic ratios of 1/1/0/0/1, 1/1/1/0.3/0.7, and 1/0.7/0.3/0.3/0.7, respectively, in synthesis mixture were prepared by coprecipitation under controlled conditions of temperature and pH. The mixed oxides were obtained by decomposition of the precursors at 500 °C in air. The characterization has been performed by XRD, ICP-ES, FT-IR, TG−DTA, TG−DTA−MS, TEM, XPS,O2-TPD, and H2-TPR. The objective is to investigate the effects of Mn and Fe partial substitution into Cu−Zn−Al mixed metal oxide derived from LDH precursor on the physicochemical and catalytic properties. The results show that the Fe and Mn substitutions decrease the structural stability of LDHs and improve the redox behavior of calcined LDHs. The activity of catalytic wet hydrogen peroxide oxidation of phenol is proportional to the content of surface metal ions and mainly Cu2+ centers linked to the surface lattice oxygen, and the degree of the deep oxidation of it is mainly related to the reactivity of the weakly bonded surface oxygen, depending on the nature of the transition metal ions in the structure. The preoxidation of phenol by surface •OH radical originating from hydrogen peroxide favors the next deep oxidation. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=22974410