Tungsten trioxide , catalyst

B. Scheffer, I.I. Heijeinga, and J.A. MouUjn, An electron spectroscopy and X-ray diffraction study of nickel oxide/alumina and nickel oxide/tungsten trioxide/alumina catalysts, J. Phys. Chem. 91, 4752 759 (1987). 

Transition metal catalysts not only increase the reaction rate but may also affect the outcome of the oxidation, especially the stereochemistry of the products. Whereas hydrogen peroxide alone in acetonitrile oxidizes alkenes to epoxides [729], osmic acid catalyzes syn hydroxylation [736], and tungstic acid catalyzes anti hydroxylation [737]. The most frequently used catalysts are titanium trichloride [732], vanadium pentoxide [733,134], sodium vanadate [735], selenium dioxide [725], chromium trioxide [134], ammonium molybdate [736], tungsten trioxide [737], tungstic acid [737],... 

Liu Y, Luo C, Liu H (2012) Tungsten trioxide promoted selective conversion of cellulose into propylene glycol and ethylene glycol on a ruthenium catalyst. Angew Chem Int Ed 51 (13) 3249-3253... 

The number of available surface sites for isopropanol adsorption of bulk tungsten trioxide and monolayer supported tungsten oxide catalysts, even mesoporous nanoparticles, is orders of magnitude (0.9-6 pmol/m ) lower than the heteropolyacids (8-55 pmol/m ). This observation cannot be attributed to the surface structure because all these materials possess polymerized WOg species with octahedral coordination (see Table 5.1). Moreover, no correlation is observed with the specific surface area and the pore diameter because high surface area, mesoporous monolayer supported catalysts possess lower Ns than HPAs. In fact. Table 5.1 shows that those materials do not possess microporosity the specific surface area is only external surface area. This observation shows that the adsorption of alcohol occurs exclusively at the outermost surface layer of WO3 and monolayer supported tungsten oxide catalysts. 

Commercial Metal Oxide SCR Catalysts. In commercial metal oxide SCR catalysts, Ti02 (in the anatase form) is used as high surface area carrier to support the active components, that is, vanadium pentoxide and tungsten trioxide (or molybdenum trioxide). The choice of Ti02-anatase as the best support for SCR catalysts relies on two main reasons ... 

Vuurman MA, Wachs IE, Hirt AM (1991) Structural determination of supported vanadium pentoxide-tungsten trioxide-titania catalysts by in situ Raman spectroscopy and x-ray photoelectron spectroscopy. J Phys Chem 95 (24) 9928—9937... 

The high cost of noble metal catalysts limited their commercial application. Advanced catalysts of both low cost and high catalytic activity, such as WO3 [62] and Mn304 [63], are studied. Yao et al. [62] prepared a carbon paper electrode coated with supported tungsten trioxide via an impregnation method, which resulted in improved electrocatalytic activity towards both VO /V02 and redox reactions. As shown in Figure 9.23a,... 

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