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

Molecules

Andreia G. Macedo¹  Sílvia E. M. Fernandes¹  Anabela A. Valente¹  Rute. A. S. Ferreira¹  Luís D. Carlos¹ 

[1] ¹Department of Physics, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal ²Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal

关键词: cerium oxide;    nanorods;    catalysis;    oxidation;    liquid phase;    free radical mechanism;   

DOI  :  10.3390/molecules15020747

来源: mdpi

【 摘 要 】

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.

【 授权许可】

CC BY   
This is an open access article distributed under the Creative Commons Attribution License (CC BY) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.