In situ generation of Mn1−xCex system on cordierite monolithic supports for combustion of n-hexane. Effects on activity and stability

CECILIA C.DIAZ; YESTE, M. PILAR; HILARIO VIDAL MUÑOZ; JOSE MANUEL GATICA; CADUS, LUIS E.; MARIA R. MORALES

FUEL

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2019 vol. 262

0016-2361

Mn1−xCex (x=0, 0.05, 0.1, 0.2 and 1) mixed oxide catalysts supported on cordierite monolith were prepared byultrasonic impregnation and examined for the catalytic combustion of n-hexane. All catalysts were characterizedin detail using N2 adsorption, XRD, XRF, SEM, XPS, H2-TPR, O2-TPD and OSC measurements. The Ce-Mn mixedcatalysts and Mn catalyst, showed excellent catalytic activity. However, the addition of cerium to manganesecatalyst did not increase its activity. The Mn-Ce mixed catalyst, with an intermediate content of Ce, presented thesame activity as the Mn catalyst, but it proved to be more stable under extreme conditions of reaction, i.e.conditions of 100% conversion at 350 °C for a maximum of 34 h. Deactivation of Mn catalyst was associated witha transformation to unstable phases of manganese oxides, while the stability of the Mn-Ce mixed catalyst wasattributed to the strong Mn-Ce interaction, which likely occurs through the formation of a small amount of solidsolution. The synthesis method used allows generating in situ a monometallic catalyst as active as a bimetallicMn-Ce catalyst under extreme reaction conditions; cheapening the cost of the catalytic system.