Control of Rh particle size of Rh/SiO2 catalysts prepared from microemulsions - Effect of surfactant

Toshiaki Hanaoka, Masahiro Kishida, Hideo Nagata, Katsuhiko Wakabayashi

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Silica-supported Rh catalysts were prepared, using W/O microemulsion composed of organic solvent, surfactant and water for the purpose of controlling Rh particle size regardless of Rh content of the catalysts. In this study, the effects of surfactants were investigated and it was found that Rh particle size could be widely varied from 3.0 to 7.0 nm by altering the type of the syrfactants. It is likely that all Rh particles were not exposed on the surface of the catalyst by this method of preparation. because the carrier was synthesized after the Rh particles were formed. The ratio of the exposed surface to the total surface of the Rh particles, accordingly, was evaluated by the ratio of the Rh particle size, calculated by CO chemisorption, to that measured by TEM. It was found that the ratios were scarcely affected by the surfactants and showed a constant value of 60%, apart from that the surfactant contained a large amount of Na. The sprecific surface areas of the catalysts were also varied to a great extent by the surfactants and time of hydrolysis of tetraethyl orthosilicate. The specific surface areas decreased as time of hydrolysis increased. These results suggest that the rate of hydrolysis and the growth of the silica formed were dependent upon the type of the surfactants.

Original languageEnglish
Number of pages1
JournalSekiyu Gakkaishi (Journal of the Japan Petroleum Institute)
Volume39
Issue number4
Publication statusPublished - Dec 1 1996

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Microemulsions
Surface active agents
Particle size
Catalysts
Hydrolysis
Silica
Chemisorption
Catalyst supports
Specific surface area
Organic solvents
Transmission electron microscopy
Water

All Science Journal Classification (ASJC) codes

  • Fuel Technology
  • Energy Engineering and Power Technology

Cite this

Control of Rh particle size of Rh/SiO2 catalysts prepared from microemulsions - Effect of surfactant. / Hanaoka, Toshiaki; Kishida, Masahiro; Nagata, Hideo; Wakabayashi, Katsuhiko.

In: Sekiyu Gakkaishi (Journal of the Japan Petroleum Institute), Vol. 39, No. 4, 01.12.1996.

Research output: Contribution to journalArticle

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