Thoria catalyst

By dropping au aromatic acid either alone or mixed with an aliphatic acid into a tube containing a thoria catalyst deposited on pumice and heated to 400-450°. This method is generally employed for the preparation of mixed aromatic - aliphatic ketones. Excess of the aUphatic acid is usually present since this leads to by-products which are easily separated and also tends to increase the yield of the desired ketone at the expense of the symmetrical ketone of the aromatic acid. Thus —... 

The mixture of carbon monoxide and hydrogen is enriched with hydrogen from the water gas catalytic (Bosch) process, ie, water gas shift reaction, and passed over a cobalt—thoria catalyst to form straight-chain, ie, linear, paraffins, olefins, and alcohols in what is known as the Fisher-Tropsch synthesis. 

Tabakova, T., Idakiev, V., Tenchev, K., Boccuzzi, F., Manzoli, M., and Chiorino, A. 2006. Pure hydrogen production on a new gold-thoria catalyst for fuel cell applications. Appl. Catal. B Environ. 63 94—103. 

Exceptional amounts of C2H4D2, such as were found over the cobalt-thoria catalyst, are not observed over metal films. 

Thoria catalyst, 735 Tischenko reactions, 318 Tollen s ammoniacal silver nitrate reagent, 330, 1061, 1074 p-Tolualdehyde, 689, 697 o-Toluamide, 798 Toluene, 510, 516, 615 purification of, 173, 174 separation from benzene, 231 p-Toluenesulphinic acid, 821, 826 o-Toluenesulphonamide, 821, 824 p-Toluenesulphonamide, 820, 823 p-Toluenesulphonates, 422, 437, 650, 684 ... 

One of the most interesting catalytic reactions to be discovered is the so-called oxo reaction. The oxo reaction consists of the catalytic addition of carbon monoxide and hydrogen to olefins to form, primarily, aldehydes possessing one carbon atom more than the original olefin. This hy-droformylation reaction was developed during World War II by Roelen and co-workers (22) in Germany. While they utilized solid Fischer-Tropsch cobalt-thoria catalyst, it became apparent to them that the hydroformylation reaction was probably a homogeneous catalytic process with either dicobalt octaearbonyl or cobalt hydrocarbonyl as the catalyst. 

The operation of a catalytic sensor depends on the oxidation of the flammable gas on the detector which is an electrically heated catalytic filament. This detector is usually made of fine platinum wire that is coated with one of several alternative substances—palladium/platinum/thoria catalysts. These catalysts help to enhance the catalytic activity and prolong the life of the detector by enabling it to operate at lower temperatures. The detector filament is connected to an identical, but inactive, unit in a Wheatstone bridge, and is located adjacent to the active detector. The identical inactive unit allows for ambient temperature compensation. 

The catalyst used in the process was a Fischer-Tropsch cobalt-thoria catalyst. The temperature was usually between 130-160° and a total pressure of 200 atm. of water gas (1II2 ICO) was usually employed. The reaction was carried out first with ethylene and the products were found to consist of a mixture of diethyl ketone and propionaldehyde. As both products contained a carbonyl or oxo group, the reaction was called the Oxo synthesis. Later it was found that ketone production was relatively unimportant aldehydes were almost always the principal... 

Symmetrical ketones (R equals ethyl, propyl, isopropyl, w-butyl, isobutyl, and -heptyl) have been prepared in nearly "quantitative" yields by passing the acid vapors over thoria at high temperatures. Studies have been made of metallic oxide catalysts and temperature of reaction. In general, a thoria catalyst has been favored at temperatures of 400-500°. The apparatus and catalyst preparation have been described. ... 

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