INVESTIGADORES
QUERINI Carlos Alberto
artículos
Título:
- K/CeO2 Catalysts Supported on Cordierite Monoliths
Autor/es:
NEYERTZ, C.A.; MIRO, E.E.; QUERINI, C.A.
Revista:
CHEMICAL ENGINEERING JOURNAL
Editorial:
ELSEVIER SCIENCE SA
Referencias:
Lugar: Amsterdam; Año: 2012 vol. 181 p. 93 - 102
ISSN:
1385-8947
Resumen:
The combination of filters and oxidation catalysts is one of the most effective aftertreatment
techniques to eliminate soot particles from the exhaust gases of diesel engines.
The activity of powder K/CeO2 catalysts has been extensively reported in the literature but
few studies refer to K/CeO2 supported on monoliths. This work presents a study of K/CeO22 catalysts has been extensively reported in the literature but
few studies refer to K/CeO2 supported on monoliths. This work presents a study of K/CeO22 supported on monoliths. This work presents a study of K/CeO2
catalysts supported on cordierite for the reaction of diesel soot combustion. The catalysts
were prepared by sequential impregnation of the monolith with ceria and different
potassium precursors. The activity was studied by temperature-programmed oxidation
(TPO) in the soot combustion with loose contact. No deactivation was observed after six
cycles of combustion-soot charge. The activity depends on the potassium precursor used,
decreasing in the order KNO3 > K2CO3 > KOH. The structural effects caused by the
different precursors of potassium determine the material activity. The X-ray diffraction
characterization does not indicate a crystalline structure change before and after reaction.
The optical microscopy and scanning electron microscope determined a redistribution of
the crystals in the monolith by heating or by the soot combustion reaction. A weight loss
during the reaction was ascribed to the degradation of the catalytic monolith. The nondeactivation
of the samples during the reaction allowed us to discard the volatilization of
the active species in the temperature range of 20 to 600 ºC, in which the tests were
performed. On the other hand, the ageing treatments at 800 ºC led to the deactivation of
K/CeO2 catalysts due to a partial loss of potassium loading.3 > K2CO3 > KOH. The structural effects caused by the
different precursors of potassium determine the material activity. The X-ray diffraction
characterization does not indicate a crystalline structure change before and after reaction.
The optical microscopy and scanning electron microscope determined a redistribution of
the crystals in the monolith by heating or by the soot combustion reaction. A weight loss
during the reaction was ascribed to the degradation of the catalytic monolith. The nondeactivation
of the samples during the reaction allowed us to discard the volatilization of
the active species in the temperature range of 20 to 600 ºC, in which the tests were
performed. On the other hand, the ageing treatments at 800 ºC led to the deactivation of
K/CeO2 catalysts due to a partial loss of potassium loading.2 catalysts due to a partial loss of potassium loading.