01816nas a2200289 4500008004100000022001400041245012100055210006900176260007300245300001400318490000600332520082400338653001401162653001401176653001401190653001801204653001301222653001601235653001201251653001801263653003301281100002601314700001401340700002501354700001801379856012901397 2007 eng d a1566-736700aSupported copper oxide as a highly active/selective catalyst for the epoxidation of styrene by TBHP to styrene oxide0 aSupported copper oxide as a highly activeselective catalyst for  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcOCT a1556-15600 v83 a

Liquid phase epoxidation of styrene by anhydrous and aqueous TBHP to styrene oxide has been studied under reflux, using different supported CuO (viz. Cuo/Si-MCM-41, CuO/Al2O3, CuO/Ga2O3 and CuO/In2O3) as easily separable and reusable heterogeneous catalysts. The CuO/Ga2O3 catalyst showed the best performance in the epoxidation by aqueous TBHP. The CuO supported on In2O3 or Si-MCM-41 also showed very good performance in the epoxidation but only by anhydrous TBHP. However, the CUO/SiO2 catalyst, however, showed very good performance in the epoxidation by both the anhydrous and aqueous TBHP. Influence of the reaction conditions (temperature, time and TBHP/styrene ratio) on the epoxidation by aqueous TBHP over the best catalyst (CuO/Ga2O3) has been investigated. (C) 2007 Elsevier B.V. All rights reserved.

10aCuO/Al2O310aCuO/Ga2O310aCuO/In2O310aCuo/Si-MCM-4110aCuO/SiO210aepoxidation10astyrene10aStyrene oxide10atertiary butyl hydroperoxide1 aChoudhary, Vasant, R.1 aJha, Rani1 aChaudhari, Nitin, K.1 aJana, Prabhas uhttps://library.ncl.res.in/content/supported-copper-oxide-highly-activeselective-catalyst-epoxidation-styrene-tbhp-styrene-001293nas a2200253 4500008004100000022001400041245016900055210006900224260007300293300001200366490000700378520038500385653000800770653001600778653000900794653000800803653001200811653001800823653000900841100002600850700001400876700001800890856013100908 2008 eng d a1566-736700aSelective epoxidation of styrene to styrene oxide by TBHP using simple transition metal oxides (NiO, CoO or MoO3) as highly active environmentally-friendly catalyst0 aSelective epoxidation of styrene to styrene oxide by TBHP using  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcNOV a205-2070 v103 a

Simple transition metal oxides, such as NiO, CoO or MoO3, etc. show high catalytic activity for the selective epoxidation of styrene to styrene oxide by TBHP. The order of choice for different transition metal oxides for epoxidation is NiO > CoO > MoO3 > Cr2O3 > Fe2O3 > ZnO >= U3O8 >> TiO2 >> MnO2. (C) 2008 Elsevier B.V. All rights reserved.

10aCoO10aepoxidation10aMoO310aNiO10astyrene10aStyrene oxide10aTBHP1 aChoudhary, Vasant, R.1 aJha, Rani1 aJana, Prabhas uhttps://library.ncl.res.in/content/selective-epoxidation-styrene-styrene-oxide-tbhp-using-simple-transition-metal-oxides-nio-003557nas a2200253 4500008004100000022001400041245010900055210006900164260007500233300001400308490000700322520266100329653001702990653001903007653001603026653002503042653002403067653001403091653001203105653001803117100002603135700002203161856012003183 2009 eng d a1022-552800aSupported nano-gold catalysts for epoxidation of styrene and oxidation of benzyl alcohol to benzaldehyde0 aSupported nanogold catalysts for epoxidation of styrene and oxid a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGER/PLENUM PUBLISHERScNOV a1677-16870 v523 a

Nano-gold particles supported on different alkaline earth oxides (viz. MgO, CaO, BaO and SrO), Gr. IIIa metal oxides (viz. Al(2)O(3), Ga(2)O(3), In(2)O(3) and Tl(2)O(3)), transition metal oxides (viz. TiO(2), Cr(2)O(3), MnO(2), Fe(2)O(3), CoO(x), NiO, CuO, ZnO, Y(2)O(3) and ZrO(2)), rare earth metal oxides (viz. La(2)O(3), Ce(2)O(3), Nd(2)O(3), Sm(2)O(3), Eu(2)O(3), Tb(2)O(3), Er(2)O(3) and Yb(2)O(3)) and U(3)O(8) [all prepared by depositing gold on corresponding metal oxide support by deposition precipitation (DP) and/or homogeneous deposition precipitation (HDP) method] were evaluated for their catalytic performance in the liquid phase epoxidation of styrene by tert-butyl hydroperoxide (TBHP) to styrene oxide and also in the solvent-free benzyl alcohol-to-benzaldehyde oxidation (by molecular oxygen or TBHP) reactions. For the epoxidation, the catalytic performance (styrene oxide yield) of the most promising nano-gold catalysts prepared by the HDP method was in the following order: Au/MgO > Au/Tl(2)O(3) > Au/Yb(2)O(3) > Au/Tb(2)O(3) > Au/CaO (or TiO(2)). However, for the oxidation of benzyl alcohol to benzaldehyde by molecular oxygen, the order of choice for the most promising catalysts (based on benzaldehyde yield) was Au/U(3)O(8) > Au/Al(2)O(3) > Au/ZrO(2) > Au/MgO. Whereas, when TBHP was used as an oxidizing agent for the benzyl alcohol oxidation, the order of choice for the most promising catalysts was Au/U(3)O(8) > Au/MgO > Au/TiO(2) > Au/ZrO(2) > Au/Al(2)O(3). The catalytic performance of a particular supported nano-gold catalyst was thus found to depend on the reaction catalysed by them. Moreover, it is strongly influenced by a number of catalyst parameters, such as the metal oxide support, the method of gold depositon on the support, the gold loading and also on the catalyst calcination temperature. Nano-gold particles-support interactions seem to play an important role in controlling the deposition of gold ( amount of gold deposited and size and morphology of gold particles), formation of different surface gold species (Au(0), Au(1+) and Au(3+)) and electronic properties of gold particles and, consequently, control the catalytic performance (both the activity and selectivity) of the supported nano-gold catalysts in the reactions. The nano-gold catalysts prepared by the HDP method showed much better catalytic performance than those prepared by the DP, coprecipitation or impregnation method; in general, the HDP method provided supported gold catalysts with much higher gold loading and/or smaller size gold particles than that achieved by the DP and other methods.

10aBenzaldehyde10aBenzyl alcohol10aepoxidation10aMetal oxide supports10aNano-gold catalysts10aOxidation10astyrene10aStyrene oxide1 aChoudhary, Vasant, R.1 aDumbre, Deepa, K. uhttps://library.ncl.res.in/content/supported-nano-gold-catalysts-epoxidation-styrene-and-oxidation-benzyl-alcohol-0