Catalytic Performance of Ceria Nanorods in Liquid-Phase Oxidations of Hydrocarbons with tert-Butyl Hydroperoxide

• Main Authors: Luís D. Carlos, Rute. A. S. Ferreira, Anabela A. Valente, Sílvia E. M. Fernandes, Andreia G. Macedo, João Rocha
• Format: Article
• Language: English
• Published: MDPI AG 2010-02-01
• Series: Molecules
• Subjects: cerium oxide; nanorods; catalysis; oxidation; liquid phase; free radical mechanism
• Online Access: http://www.mdpi.com/1420-3049/15/2/747/

The CeO2 nanorods (CeNR) promote the oxidation of ethylbenzene (PhEt) and cyclohexene with t-BuOOH, at temperatures as low as 55 ºC. For both substrates the saturated C-H bonds are preferentially activated over the unsaturated ones. The catalyst seems fairly stable towards leaching phenomena. The liquid-phase oxidation catalysis may be associated with the Ce3+/Ce4+ inter-conversion in the one-electron redox processes mediating the formation of tert-butyl-(per)oxy radicals. CeNR is very effective in H2O2 disproportionation. Pre-treatment of CeNR with H2O2 or t-BuOOH prior to the catalytic reaction enhances the reaction rate of PhEt with t-BuOOH in comparison to CeNR. Textural characterization and spectroscopic studies suggest that catalytic activation is associated to defect sites.