TEM Study of the Microstructural Modifications of an Alumina-Supported Palladium Combustion Catalyst

The Activation of a Pd/γ-alumina Catalyst During Methane Combustion: Investigation of the Phenomenon and of Potential Causes

“…The sole sintering phenomenon does not explain the full activation process since it does not vary with time-on-stream at 550°C whereas the catalytic activity does. The increase of activity with the size of the palladium particles has already been reported and would reflect some structure sensitivity of the CCM reaction on Pd-supported catalysts [3,4,7,12,14,15,19,28,29,34]. However, other researchers came to opposite conclusions, claiming that there is no correlation between the activity and the particle size of the Pd-supported catalyst [17,20,35].…”

“…The evolution of activity of Pd-supported catalysts during CCM is a controversial and contradictory issue. Some authors reported activation of the catalyst with time-on-stream [7,[13][14][15][16][17][18][19][20][21][22][23], whereas other researchers mentioned deactivation phenomena [24,25], while some others observed varying behaviors [4,11,12,[26][27][28][29] depending on the reaction conditions and/or on the catalyst characteristics. In this paper, we study the catalytic combustion of methane on a palladium aluminasupported catalyst (Pd/c-Al 2 O 3 ) as function of the temperature and the time on stream.…”

Enhanced hydrothermal stability of high performance lean fuel combustion alumina-supported palladium catalyst modified by nickel

“…CH 4 diffused and chemisorbed on the surface of the catalyst, whereafter it dissociated and was oxidized to CO 2 and H 2 O. Normally, CH 4 prefers to combust on Pd/Al 2 O 3 catalyst, and its combustion performance is considered to be dependent on the stability and activity of the catalyst [49,50].…”

Growth and decomposition of aligned and ordered PdO nanoparticles

“…[7] Comparatively little studies on the interaction of Pd with oxygen have been conducted by electron microscopy techniques. Lyubovsky et al [24] and Datye et al [11] reported on microstructural modifications of impregnated Pd-Al 2 O 3 catalysts during the transformation from Pd to PdO and established a correlation to the reactivity in methane oxidation. Electron microscopy was also used to characterize the state of Pd during other hydrocarbon oxidation reactions.…”