| Nome: | Descrição: | Tamanho: | Formato: | |
|---|---|---|---|---|
| 316.23 KB | Adobe PDF | |||
| 27.02 KB | Adobe PDF |
Orientador(es)
Resumo(s)
Carbon-supported iridium catalysts were prepared by different incipient wetness impregnation methods and by organometallic
chemical vapor deposition. The catalysts were characterized by N2 adsorption, TPD, SEM and H2 chemisorption measurements.
The results obtained indicate a clear dependency of the metal-phase dispersion on the pre-treatment of the carbon support and the impregnation method. Their activity for catalytic wet air oxidation of butyric and iso-butyric acid aqueous solutions was investigated in a stirred reactor at 473K and 0.69MPa of oxygen partial pressure. The conversions obtained after 2 h were 43 and 52%,with respect to each carboxylic acid, when the most active catalysts were used. The measured conversions and initial reaction rates correlate well with the exposed metal area. A rate equation was determined from measurements of the initial reaction rates at different oxygen partial pressures, temperatures and catalyst mass loads. The results were modeled considering a heterogeneously catalyzed free-radical mechanism.
Descrição
Palavras-chave
Catalytic wet air oxidation Carbon-supported iridium catalysts Incipient wetness impregnation Organometallic chemical vapor deposition Heterogeneous-catalyzed free-radical mechanism
Contexto Educativo
Citação
Gomes, Helder; Figueiredo, José; Faria, Joaquim; Serp, Philippe; Kalck, Philippe (2002). Carbon supported iridium catalysts in the catalytic wet air oxidation of carboxylic acids: kinetics and mechanistic interpretation. Journal of Molecular Catalysis A: Chemical. ISSN 1381-1169. 182:1 Special Issue: SI, p. 47-60
Editora
Elsevier