Preparation of titanium molecular species supported on mesostructured silica by different grafting methods

Titanium supported on SBA-15 mesoporous silica has been synthesised containing different titanium loadings prepared by chemical grafting using titanocene dichloride as precursor and over different treated silica surfaces. A comparative study using MCM-41 mesoporous silica as support is also reported...

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Detalles Bibliográficos
Autores: Calleja, G., van Grieken, R., García-Muñoz, Rafael A., Melero, J.A., Iglesias, Jose
Tipo de recurso: artículo
Fecha de publicación:2002
País:España
Institución:Universidad Rey Juan Carlos
Repositorio:BURJC-Digital. Repositorio Institucional de la Universidad Rey Juan Carlos
OAI Identifier:oai:burjcdigital.urjc.es:10115/3736
Acceso en línea:http://hdl.handle.net/10115/3736
Access Level:acceso abierto
Palabra clave:Materiales
23 Química
Descripción
Sumario:Titanium supported on SBA-15 mesoporous silica has been synthesised containing different titanium loadings prepared by chemical grafting using titanocene dichloride as precursor and over different treated silica surfaces. A comparative study using MCM-41 mesoporous silica as support is also reported. The type of silica support and its surface properties as well as the initial concentration of Ti precursor in the organic solution influences clearly the incorporation of Ti species. The materials after grafting treatment were characterized by different conventional techniques including XRD, FT-IR DR UV-Vis and nitrogen adsorption. The titanium containing SBA-15 silica shows hexagonal mesoscopic order and pore sizes up to 70 Å with surface areas up to 600 m2/g and titanium content ranging from 1 to 3 wt. %. DR UV-Vis of Ti containing SBA-15 silica after removal of the organic ligand shows the presence of Ti isolated species tetrahedrally coordinated and the absence of bulky TiO2 phases. Likewise, these materials upon calcination were catalytically active for the epoxidation of styrene with TBHP exhibiting a significant selectivity toward the epoxide.