CO oxidation: Deactivation of Au/TiO2 catalysts during storage
2009; Springer Science+Business Media; Volume: 42; Issue: 4 Linguagem: Inglês
10.1007/bf03214955
ISSN0017-1557
AutoresMpfunzeni Raphulu, J. McPherson, Gary Pattrick, Thabang Ntho, Lebohang Mokoena, John Moma, Elma van der Lingen,
Tópico(s)Industrial Gas Emission Control
ResumoIn a study of the phenomenon of catalyst deactivation during storage, Au/TiO2 catalyst was stored under various conditions, viz. vacuum, nitrogen, air, refrigeration, dark, and light, and tested for CO oxidation activity at regular intervals. The data shows that the catalyst deactivates under all the storage conditions over 12 months and that storage in vacuum significantly enhances the rate and extent of deactivation. Storage in light accelerates the deactivation. The catalyst appears to deactivate through a combination of Au(III) reduction, Au nanoparticle agglomeration, loss of surface hydroxyl groups, loss of surface moisture, and accumulation of surface carbonates and formates. The rate and extent of catalyst deactivation can be limited by storing the catalyst in the dark at sub ambient temperature (refrigerator) and under inert atmosphere.
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