Preparation of rhodium catalysts dispersed on TiO2single bondSiO2 aerogels. Cauqui, M., Calvino, J., Cifredo, G., Esquivias, L., & Rodríguez-Izquierdo, J. Journal of Non-Crystalline Solids, 147-148(C):758-763, 1992. cited By 22
Preparation of rhodium catalysts dispersed on TiO2single bondSiO2 aerogels [link]Paper  doi  abstract   bibtex   
TiO2single bondSiO2 aerogels have been used as supports to disperse rhodium. Three different ways have been followed for the preparations: (a) a classic TiO2single bondSiO2 aerogel, obtained from a mixture of alkoxides and water dissolved in ethanol, was impregnated with a rhodium nitrate solution; (b) a TiO2single bondSiO2 sonogel, obtained by hydrolysis of alkoxides in the absence of alcohol, under the action of ultrasound, was impregnated with a rhodium nitrate solution; and (c) a mixture of alkoxides and water, including rhodium nitrate in the reaction vessel, was exposed to the action of ultrasound, thus leading to a ternary Rhsingle bondTiO2single bondSiO2 sonogel. The behaviour of these three catalysts has been compared with that of a Rh/TiO2single bondSiO2 system (d), obtained by conventional impregnation methods, starting from a commercial silica support. The samples prepared by impregnation of aerogels (a,b) present high levels of rhodium dispersion and show an increase of the catalytic activities in parallel with the pretreatment temperature in flow of hydrogen. On the contrary, the sample prepared including rhodium before gelling (c) presents a poor metallic dispersion, is not active for benzene hydrogenation, and has the capability of uptaking large amounts of hydrogen at ambient temperature. Both patterns of behaviour are greatly different from that characteristic of conventional Rh/TiO2single bondSiO2 catalyst (d). © 1992 Elsevier Science Publishers B.V. All rights reserved.
@ARTICLE{Cauqui1992758,
author={Cauqui, M.A.a  and Calvino, J.J.a  and Cifredo, G.a  and Esquivias, L.b  and Rodríguez-Izquierdo, J.M.a },
title={Preparation of rhodium catalysts dispersed on TiO2{single bond}SiO2 aerogels},
journal={Journal of Non-Crystalline Solids},
year={1992},
volume={147-148},
number={C},
pages={758-763},
doi={10.1016/S0022-3093(05)80712-4},
note={cited By 22},
url={https://www.scopus.com/inward/record.url?eid=2-s2.0-0026931941&partnerID=40&md5=31c7529c16c00585bf5012b7d821c3f7},
affiliation={Department of Inorganic Chemistry, University of Cadiz, Apartado 40, Puerto Real, 11510, Spain; Department of Structure and Properties of Materials, University of Cadiz, Apartado 40, Puerto Real, 11510, Spain},
abstract={TiO2{single bond}SiO2 aerogels have been used as supports to disperse rhodium. Three different ways have been followed for the preparations: (a) a classic TiO2{single bond}SiO2 aerogel, obtained from a mixture of alkoxides and water dissolved in ethanol, was impregnated with a rhodium nitrate solution; (b) a TiO2{single bond}SiO2 sonogel, obtained by hydrolysis of alkoxides in the absence of alcohol, under the action of ultrasound, was impregnated with a rhodium nitrate solution; and (c) a mixture of alkoxides and water, including rhodium nitrate in the reaction vessel, was exposed to the action of ultrasound, thus leading to a ternary Rh{single bond}TiO2{single bond}SiO2 sonogel. The behaviour of these three catalysts has been compared with that of a Rh/TiO2{single bond}SiO2 system (d), obtained by conventional impregnation methods, starting from a commercial silica support. The samples prepared by impregnation of aerogels (a,b) present high levels of rhodium dispersion and show an increase of the catalytic activities in parallel with the pretreatment temperature in flow of hydrogen. On the contrary, the sample prepared including rhodium before gelling (c) presents a poor metallic dispersion, is not active for benzene hydrogenation, and has the capability of uptaking large amounts of hydrogen at ambient temperature. Both patterns of behaviour are greatly different from that characteristic of conventional Rh/TiO2{single bond}SiO2 catalyst (d). © 1992 Elsevier Science Publishers B.V. All rights reserved.},
document_type={Article},
source={Scopus},
}

Downloads: 0