Catalytic filters for the simultaneous removal of soot and NO x: Effect of CO 2 and steam on the exhaust gas of diesel engines

Gálvez M.E.; Ascaso S.; Moliner, R.; Lazaro M.J.; Jimenez, R; García X.; Gordon A.

Keywords: oxidation, no, reduction, dust, gas, alumina, co, nitrogen, filter, mechanism, removal, minerals, xrd, oxide, dioxide, catalysts, filters, selectivity, carbon, oxides, active, bed, catalyst, silicate, activity, diesel, steam, soot, properties, physisorption, cordierite, cleaning, monolith, sem-edx, chemical, of, Reaction, effect, nitric, High, Simultaneous, fixed, engines, Catalytic, Temperature-programmed, exhausts, Monolithic, Washcoats

Abstract

Catalytic filters for the simultaneous removal of soot and nitrogen oxides were prepared by means of coating cordierite monoliths with alumina-based suspensions containing Cu, Co or V and K as the catalytically active phase. Textural and chemical properties of the coated monoliths were determined by means of N 2-physisorption, XRD, SEM-EDX and temperature programmed reduction. Activity of the catalytic filters in the simultaneous removal of soot and nitrogen oxides was tested in a fixed bed installation in absence and in presence of steam and CO 2. Complete soot oxidation was measured for some of the assayed catalytic filters, with high selectivity to CO 2 formation. NO reduction was preceded by a peak of NO 2 formation, which corresponded to maximum soot oxidation rate, pointing to the formation of NO 2 as a key step in the reaction mechanism for the simultaneous removal. Presence of steam and CO 2 diminished catalytic activity and selectivity for soot oxidation. © 2011 Elsevier B.V.

Más información

Título de la Revista: CATALYSIS TODAY
Volumen: 176
Número: 1
Editorial: Elsevier
Fecha de publicación: 2011
Página de inicio: 134
Página final: 138
URL: http://www.scopus.com/inward/record.url?eid=2-s2.0-79959823710&partnerID=q2rCbXpz