Soot Combustion on Electrochemical Solid-State Catalysts

L. LIZARRAGA; S. SOUENTIE; L. MAZRI; P.VERNOUX

Niza

Encuentro; The 61st Annual Meeting of the International Society of Electrochemistry; 2010

International Society of Electrochemistry

Soot particles formed by incomplete combustion of fossil fuels and biomass affect radiative forcing, with an overall contribution to global warming estimated to be second after that due to CO2 [1-2]. The use of particulates filters in Diesel exhausts is a current approach to avoid the release of soot to the atmosphere. In the present work, soot combustion was studied using a novel approach based on electrochemical catalysts. These systems consist of porous thin metal films (Pt, Ag, etc) deposited on different solid state conductors (Y2O3-stabilized ZrO2, K-β?? Al2O3) pellets [3]. Soot was generated by a Combustion Aerosol Standard Soot Generator using propane as fuel. Soot particles were collected at the exit of the generator over the surface of porous metal films. Different electrochemical tests were carried out to study the soot combustion. Figure 1 presents the CO2 formation from the soot in the electrochemical catalyst Pt / YSZ at 400 °C in He. It also shows the potential between the Pt film and the gold reference electrode when a current of + 400 uA was applied. Soot oxidation is due to the electrochemical migration of O2- from YSZ to the Pt surface where they react with the soot particles to produce CO2 [4]. Besides, electrochemical promotion of catalysis [3] was evaluated on the soot combustion with our electrochemical catalysts in presence of oxygen traces