A study of the activity and durability of two different copper chromite catalysts in methane combustion is presented. The catalysts, a massive (CAT-E) and a supported (CAT-I) copper chromite, were characterized by different techniques in order to investigate morphological properties (N2 adsorption), crystalline structure (X-ray diffraction, XRD) and surface composition (X-ray photoelectron spectroscopy, XPS). Among the different crystalline phases identified, CuCr2O4 spinel represented the common phase in both the catalysts. The CrVI/CrIII surface ratio was almost the same for the two catalysts, while the CuII/CuI surface ratio was much higher on the massive catalyst than on the supported one. The activity for CH4 combustion was studied in the temperature range 300-700°C at constant CH4 : air ratio of 1 : 30 and constant methane content, 1.2%. The activity was higher for CAT-I and CAT-E showed better stability. A kinetic study from the catalytic data, collected at different contact times in the interval 0.047- 0.315 s as a function of temperature, provided a value of about 110 kJ/mol for the activation energy. This value was obtained for various degrees of methane converted for the two catalysts. The reaction rates were between 10-3 and 10-4 (molCH4)convconv/(g h) in the temperature interval 550-700°C, for both the catalysts.
Methane combustion over copper chromite catalysts / G. Comino, A. Gervasini, V. Ragaini, Z. Ismagilov. - In: CATALYSIS LETTERS. - ISSN 1011-372X. - 48:1-2(1997), pp. 39-46.
|Titolo:||Methane combustion over copper chromite catalysts|
GERVASINI, ANTONELLA (Secondo)
RAGAINI, VITTORIO (Penultimo)
|Settore Scientifico Disciplinare:||Settore CHIM/02 - Chimica Fisica|
|Data di pubblicazione:||1997|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1023/A:1019070819421|
|Appare nelle tipologie:||01 - Articolo su periodico|