02310nas a2200253   4500008004100000022001400041245008900055210006900144260007300213300001100286490000600297520140500303653002301708653001401731653003401745653003201779653001501811653001401826653003001840100002601870700001701896700002601913856011701939       2005                        eng d  a1566-736700aInfluence of PdO content and pathway of its formation on methane combustion activity0 aInfluence of PdO content and pathway of its formation on methane  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcFEB  a97-1000 v63 a<p>The methane oxidation reaction is known to induce changes in the surface structure and composition of Pd catalysts; making it extremely arduous to relate the methane oxidation activity to specific catalyst properties by conventional methods (continuous flow reactor studies). To circumvent this, methodical pulse reactor studies have been undertaken to obtain correlations between the initial methane combustion activity and the catalyst properties (Pd-0/PdO content and path of PdO formation). While the initial methane combustion activity (at 160-280 degreesC) continuously increased with increasing PdO concentration (0-100%) in the catalyst, it continuously decreased with increasing Pddegrees content (0-100%). Controlled studies were undertaken to obtain catalysts with identical PdO content by two pathways: (i) by controlled partial oxidization of Pd-0/Al2O3 and (ii) by controlled partial reduction of PdO/Al2O3. Interestingly, for a given PdO content, the catalysts obtained by partial oxidation of Pd-0/Al2O3 showed a significantly superior performance to the catalyst obtained by partial reduction of PdO/Al2O3 for all the temperatures investigated. These studies unambiguously show that along with the relative concentration of PdO, the PdO formation pathway is also critical in deciding the methane combustion activity of the catalyst. (C) 2004 Elsevier B.V. All rights reserved.</p>10aMethane combustion10aOxidation10apartially oxidized Pd-0/Al2O310apartially reduced PdO/Al2O310aPd-0/Al2O310aPdO/Al2O310apulse reaction of methane1 aChoudhary, Tushar, V.1 aBanerjee, S.1 aChoudhary, Vasant, R.  uhttps://library.ncl.res.in/content/influence-pdo-content-and-pathway-its-formation-methane-combustion-activity-002430nas a2200241   4500008004100000022001400041245015300055210006900208260007300277300001200350490000800362520146900370653001301839653002901852653004101881653002301922653003401945100002601979700001802005700001802023700001902041856012802060       2008                        eng d  a0926-860X00aNano-gold supported on Fe2O3: a highly active catalyst for low temperature oxidative destruction of methane green house gas from exhaust/waste gases0 aNanogold supported on Fe2O3 a highly active catalyst for low tem  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcNOV  a186-1900 v3503 a<p>A number of nano-gold catalysts were prepared by depositing gold on different metal oxides (viz. Fe2O3, Al2O3, Co3O4, MnO2, CeO2, MgO, Ga2O3 and TiO2), using the homogeneous deposition precipitation (HDP) technique. The catalysts were evaluated for their performance in the combustion of methane (1 mol% in air) at different temperatures (300-600 degrees C) for a GHSV of 51,000 h(-1). The supported nano-gold catalysts have been characterized for their gold loading (by ICP) and gold particle size (by TEM/HRTEM or XRD peak broadening). Among these nano-gold catalysts, the Au/Fe2O3 (Au loading = 6.1% and Au particle size = 8.5 nm) showed excellent performance. For this catalyst, temperature required for half the methane combustion was 387 degrees C, which is lower than that required for Pd(1%)/Al2O3 (400 degrees C) and Pt(1%)/Al2O3 (500 degrees C) under identical conditions. A detailed investigation on the influence of space velocity (GHSV = 10,000-100,000 cm(3) g(-1) h(-1)) at different temperatures (200-600 degrees C) on the oxidative destruction of methane over the Au/Fe2O3 catalyst has also been carried out. The Au/Fe2O3 catalyst prepared by the HDP method showed much higher methane combustion activity than that prepared by the conventional deposition precipitation (DP) method. The XPS analysis showed the presence of Au in the different oxidation states (Au-0, Au1+ and Au3+) in the catalyst. (C) 2008 Elsevier B.V. All rights reserved.</p>10aAu/Fe2O310aDeposition precipitation10aHomogeneous deposition precipitation10aMethane combustion10aSupported nano-gold catalysts1 aChoudhary, Vasant, R.1 aPatil, V., P.1 aJana, Prabhas1 aUphade, B., S.  uhttps://library.ncl.res.in/content/nano-gold-supported-fe2o3-highly-active-catalyst-low-temperature-oxidative-destruction-0