In situ spectroscopic studies of methane catalytic combustion over Co, Ce, and Pd mixed oxides deposited on a steel surface

Surface structure of cobalt, palladium, and mixed oxide‐based catalysts and their activity in methane combustion studied by means of micro‐Raman spectroscopy

“…Interestingly, catalyst conversion is slightly different for comparable catalysts prepared by the standard and sonicated methods for palladium. The obtained results on γ‐Al 2 O 3 supported catalysts in comparison to our previous study on structured catalysts (γ‐Al 2 O 3 washcoated on kanthal steel) show similar activity of sonicated catalysts to the reported Co1Pd0.001 and Pd0.001 catalysts deposited on kanthal steel. However, the supported catalysts prepared by standard wetness method reveal the shift of light‐off temperatures to the higher values.…”

“…For bimetallic catalysts, the predicted activity should be better than monometallic; thus, the cobalt loaded on the catalysts may lead to the activation of Pd 0 /PdO species . The high activity of palladium doped cobalt catalysts is consisted with other works based on the same active metals reported in literature . Synergism on the addition of small amount of palladium to cobalt was observed also for the CO hydrogenation .…”

Towards Methane Combustion Mechanism on Metal Oxides Supported Catalysts: Ceria Supported Palladium Catalysts

“…The phenomenon of high activity of highly dispersed metal oxides including palladium in methane combustion has already been well established in the literature [61]. It has also been pointed out in our previous works [62,63]. In this Fig.…”

“…It has also been a subject of debate whether catalytic combustion proceeds via the Eley-Rideal or Langmuir-Hinshelwood mechanisms [2,67]. According to our study, methane was shown not to adsorb directly on the catalyst surface, but only in the oxygen preadsorbed surface which proves that the Langmuir-Hinshelwood mechanism can be excluded [62]. It should also be noted, that precise distinctions distinction between the Mars-van Krevelen and Eley-Rideal mechanisms is hard to achieve.…”

“…As pointed out in the introduction, the mechanism of methane combustion is still far from being fully understood. It is discussed in our previous work [62]. In that paper, different reaction intermediates are considered on the basis of in situ FTIR studies.…”