01083nas a2200193 4500008004100000022001400041245016200055210006900217260011000286300001200396490000600408520025500414100002600669700001300695700001800708700001400726700001900740856013000759 2005 eng d a1463-926200aGreen process for chlorine-free benzaldehyde from the solvent-free oxidation of benzyl alcohol with molecular oxygen over a supported nano-size gold catalyst0 aGreen process for chlorinefree benzaldehyde from the solventfree aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcOCT a768-7700 v73 a

Benzyl alcohol is oxidized selectively to benzaldehyde with high yield, with a little formation of benzylbenzoate, by molecular oxygen over a reusable nano-size gold catalyst supported on U3O8, MgO, Al2O3 or ZrO2 in the absence of any solvent.

1 aChoudhary, Vasant, R.1 aDhar, A.1 aJana, Prabhas1 aJha, Rani1 aUphade, B., S. uhttps://library.ncl.res.in/content/green-process-chlorine-free-benzaldehyde-solvent-free-oxidation-benzyl-alcohol-molecular-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

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.

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-002101nas a2200253 4500008004100000022001400041245024000055210006900295260009500364300001200459490000800471520100600479653002201485653002701507653002301534653001801557653002901575100002601604700002201630700001801652700001901670700002801689856013001717 2013 eng d a0021-951700aEpoxidation of styrene by t-butyl hydroperoxide over gold nanoparticles supported on Yb2O3: effect of gold deposition method, gold loading, and calcination temperature of the catalyst on its surface properties and catalytic performance0 aEpoxidation of styrene by tbutyl hydroperoxide over gold nanopar a525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USAbACADEMIC PRESS INC ELSEVIER SCIENCEcAPR a217-2240 v3003 a

Surface properties and epoxidation performance of Au/Yb2O3 catalyst are influenced by the method of gold deposition [viz. deposition-precipitation (DP), homogeneous deposition-precipitation (HDP) or impregnation], gold loading (0.9-6.6 wt%), and the catalyst calcination temperature (400-900 degrees C)]. The catalyst showed the best epoxidation performance when it was prepared by the HDP method and calcined at 500 degrees C. The Au/Yb2O3 catalyst even after calcination at 900 degrees C showed good activity and epoxide selectivity. Both Au-0 and Au3+ surface species were found in the catalyst calcined at 800 degrees C, but only Au-0 species were observed at the lower calcination temperatures (<600 degrees C). The selectivity for styrene oxide increased continuously with the reaction temperature (from 75 degrees C to 97 degrees C) and time (1-5 h), indicating that styrene oxide did not undergo secondary reactions under these conditions. (C) 2013 Elsevier Inc. All rights reserved.

10aAu/Yb2O3 catalyst10aEpoxidation of styrene10agold nanoparticles10aStyrene oxide10atert-Butyl hydroperoxide1 aChoudhary, Vasant, R.1 aDumbre, Deepa, K.1 aPatil, N., S.1 aUphade, B., S.1 aBhargava, Suresh, Kumar uhttps://library.ncl.res.in/content/epoxidation-styrene-t-butyl-hydroperoxide-over-gold-nanoparticles-supported-yb2o3-effect-0