Development of Catalysts Supported in Ceramic Monoliths For the Elimination of Polluting Agents of Diesel Engines

M. J. FERNÁNDEZ TASSO, C. A. QUERINI

Rio de Janeiro -Brasil

Congreso; ENPROMER 2005; 2005

Emissions from diesel engines constitute one of the main causes of environmental pollution. In this work, catalyst supported on a ceramic monolith are studied in the soot oxidation reaction. The objective is to reproduce the K/La2O3 catalyst, which in its powder form mixed with soot gave maximum combustion rates between 350 and 370°C during TPO analysis. The preparation is studied, by loading the lanthanum as oxide from suspension in water, or by impregnation with lanthanum nitrate, followed by calcination. It was deposited in one or several steps. The effect of potassium hydroxide during impregnation was also addressed. Catalysts prepared from lanthanum nitrate displayed a better performance regarding adherence to the substrate, with larger areas of the monolith uncovered when using the oxide. Increasing the concentration of potassium hydroxide during impregnation leads to an improved quality of the deposit. Catalysts thus obtained showed a lower activity for soot oxidation, which is ascribed to a poored contact between the soot and the catalyst.