Platinum alumina

This mechanistic interpretation is based on the assumption that, once formed, five- or six-membered products of dehydrocyclization do not undergo interconversion. As discussed above, isomerizations are extremely slow at 317°C for tetralin to methylindan and methylindan to tetralin over alumina, silica-alumina, platinum-on-alumina, and platinum-on-silica-alumina catalysts (22, 23). 

All side-chain isomers are formed in acid-catalyzed isomerization. Carbonium ions are the intermediates here. Over dual-function catalysts, such as platinum-on-alumina and platinum-on-silica-alumina, platinum increases the rate of isomerization by dehydrogenating alkanes to olefins. This facilitates the formation of carbonium ions. 

Figure 3 Typical quartz plasma torch positioned within a (induction) load coil. The center (injector) tube can be made of quartz or inert materials (alumina, platinum, or sapphire) to allow corrosive samples (including those containing hydrofluoric acid) to be introduced into the plasma. One-piece quartz torches, torches with demountable injector tubes, or completely demountable tubes are used.

When the metal is introduced, the scattering is changed, but the observed scattering is now due to alumina-air, platinum-air, and alumina-platinum. There is no way in which the scattering can be correlated directly to the platinum size, since no way can be found to correct the background scattering. 

Haensel, V., inventor Universal Oil Products Company, assignee. "Alumina-platinum-halogen catalyst and preparation thereof." U.S. Patent 2,479,109. 7 pages. August 16, 1949. 

Chloroplatinic acid, platinum on carbon or alumina, platinum(II) complexes with olefins, and platinum(O) complexes with phosphines have been used . Among them,... 

One common refomiing catalyst is platinum on alumina. Platinum on alumina (AUOO (see SEM photo below) is a bifunctional catalyst that can be prepared by exposing alumina pellets to a chloroplatinic acid solution, drying, and then heating in air 775 to 875 K for several hours. Next, the material is exposed to hydrogen at temperatures around 725 to 775 K to produce very small clusters of Pt on alumina. These clusters have sizes on the order of lO A. while the alumina pore sizes on which the Pi is deposited are on the order of 100 to 10.0(K) A (i.e., 10 to 1000 nm). 

Chloroplatinic acid, platinum on carbon or alumina, platinum(II) complexes with olefins, and platinum(O) complexes with phosphines have been used for hydrosilylation1,2. Chloroplatinic acid, H2PtCl6-6H20, is by far the most commonly used and efficient catalyst particularly for the hydrosilylation of a variety of olefinic substrates1 4. Chloroplatinic acid is frequently used as a solution in isopropanol and this system is referred to as Speier s catalyst , in recognition of the work of J. L. Speier in the discovery of its usefulness. 

Crude oil Hydrocarbon fuels Platinum/silica-alumina Platinum/acidic alumina Metal-exchanged zeolites no9... 

Figure 6.41. Evolution of surface potential as a function of oxygen pressure (1 mbar = 100 Pa) beta-alumina - platinum structure...

RC-10 Pt reduction column Pt-reducing column 10% R on Alumina Platinum-black catalyst... 

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