Modulation of selective sites by introduction of N2O, CO2 and H2 as gaseous promoters into the feed during oxidation reactions

Investigation of the behaviour of a Pd/γ-Al2O3 catalyst during methane combustion reaction using in situ DRIFT spectroscopy

“…Moreover, this oxidized surface state after test was observed even after an in situ reducing pre-treatment [30], or after a test in presence of low amounts of H 2 in the CCM feed [31,32].…”

“…Indeed, the oxidized surface of the palladium particles would be more quickly reduced when H 2 is added to the feed than in presence of sole CH 4 . This interpretation is based on results of a study focused on the influence of the presence of H 2 in the CCM feed upon the reduction of the surface of the palladium particles [31,32]. The 1900 cm À1 peak appears more rapidly in these conditions, because of the more reductive atmosphere.…”

“…In addition, this investigation was also motivated by the experimental observation that, in our conditions, the surface of a powdered Pd (2 wt.%)/g-Al 2 O 3 catalyst was always in www.elsevier.com/locate/apcata Applied Catalysis A: General 295 (2005) [59][60][61][62][63][64][65][66][67][68][69][70] oxidized form after a conventional micro-reactor test [29][30][31][32]. Moreover, this oxidized surface state after test was observed even after an in situ reducing pre-treatment [30], or after a test in presence of low amounts of H 2 in the CCM feed [31,32].…”

Influence of the addition of H2 upon the behavior and properties of a Pd(2wt.%)/γ-Al2O3 catalyst and a comparison with the case of the Pt-based catalyst

“…In that sense, from a fundamental point of view, adding H 2 to the feed could be a useful tool to shed some light on the state of the catalyst and on the stability of such surface oxygen layer during the reaction. H 2 can modify the surface state of palladium particles and/or perturb the surface oxygen layer, influencing the activity and/or selectivity to CO 2 [15]. In addition, any change of the temperature of the catalytic sites leads to important changes in the catalytic performances and, more precisely, in the efficiency of the combustion process.…”

A facile ceria–zirconia binary oxide used for degradation of 2-chloroethyl ethyl sulfide

“…The species O II with B.E. & 531.0 eV is most likely to belong to hydroxyl bonded to metal (OH -)[41,42] and carbonate species (CO3 2-)[43,44]. The species O III with the low binding energy (B.E.…”