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Effect of sulfate modification on structure properties, surface acidity, and transesterification catalytic performance of titanium - submitted mesoporous molecular sieve / Shengping Wang in Industrial & engineering chemistry research, Vol. 51 N° 16 (Avril 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 16 (Avril 2012) . - pp. 5737-5742 Titre : Effect of sulfate modification on structure properties, surface acidity, and transesterification catalytic performance of titanium - submitted mesoporous molecular sieve Type de document : texte imprimé Auteurs : Shengping Wang, Auteur ; Yun Shi, Auteur ; Xinbin Ma, Auteur Année de publication : 2012 Article en page(s) : pp. 5737-5742 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Molecular  sieve  Catalytic  reaction  Transesterification  Acidity Résumé : A series of sulfated titanium-submitted mesoporous molecular sieves denoted as S/Ti-MCM-41 were prepared by wet impregnation method with H2SO4 solution as promoter. The results of XRD, N2 adsorption-desorption, NH3-TPD, FTIR of pyridine adsorption, and XPS analysis indicated that S/Ti-MCM-41 samples possess well-ordered hexagonal mesostructure, although the pore diameter and specific surface area shrunk with the increasing coverage of sulfur species. As a result of the electron inductive effect from the S=O bond of SO42-, Lewis acidity is intensified significantly and new Brönsted acid sites are generated from the activated hydroxyl groups. Brönsted acid sites are medium strength, while part of the Lewis acid sites are of weak strength and part of them are medium. The S/Ti-MCM-41 catalysts exhibited desirable activity for transesterification of dimethyl oxalate and phenol. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25834487 [article] Effect of sulfate modification on structure properties, surface acidity, and transesterification catalytic performance of titanium - submitted mesoporous molecular sieve [texte imprimé] / Shengping Wang, Auteur ; Yun Shi, Auteur ; Xinbin Ma, Auteur . - 2012 . - pp. 5737-5742. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 16 (Avril 2012) . - pp. 5737-5742 Mots-clés : Molecular  sieve  Catalytic  reaction  Transesterification  Acidity Résumé : A series of sulfated titanium-submitted mesoporous molecular sieves denoted as S/Ti-MCM-41 were prepared by wet impregnation method with H2SO4 solution as promoter. The results of XRD, N2 adsorption-desorption, NH3-TPD, FTIR of pyridine adsorption, and XPS analysis indicated that S/Ti-MCM-41 samples possess well-ordered hexagonal mesostructure, although the pore diameter and specific surface area shrunk with the increasing coverage of sulfur species. As a result of the electron inductive effect from the S=O bond of SO42-, Lewis acidity is intensified significantly and new Brönsted acid sites are generated from the activated hydroxyl groups. Brönsted acid sites are medium strength, while part of the Lewis acid sites are of weak strength and part of them are medium. The S/Ti-MCM-41 catalysts exhibited desirable activity for transesterification of dimethyl oxalate and phenol. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25834487