ISSN:
1662-9779
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Physics
Notes:
High surface area nano-sized catalysts with the general formula La0.9M0.1CoO3 (M=Ce,Pr, Tb) were synthesised by a novel flame-spray-pyrolysis method. All the prepared samplespossessed the LaCoO3 perovskite-like structure and consisted of 30-60 nm particles, but existing aslarge (80-200 nm) agglomerates. Their surface area ranged from 45 to 60 m2/g. All the catalystsshowed a very high activity for methane flameless combustion, attaining 100% conversion attemperatures Tf, between 495 and 515 0C, depending on the nature of the M doping ion. The resultsof life-tests did not show any decreasing of catalytic activity after 50 h under the reaction conditionsat Tf. The thermal stability under high temperature application was investigated by overheating thecatalysts twice at 800 0C for 1 hr in a flowing reacting gas mixture, fast deactivation cycles, andthen measuring methane conversion at Tf. All the catalysts showed a significant decrease ofactivity, depending on the chemical composition. Taking account of the results of SEM analysis,this was attributed to sintering, connected with the Gibbs instability of nano-sized materials
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/24/transtech_doi~10.4028%252Fwww.scientific.net%252FSSP.128.255.pdf
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