Adsorption and catalytic reactions on evaporated metal films. VII. Adsorption of krypton and hydrogen on thermally non-stabilized nickel films

1963 ◽  
Vol 28 (4) ◽  
pp. 942-949
Author(s):  
Z. Knor ◽  
V. Ponec
Keyword(s):  
Metal Films ◽  
Catalytic Reactions ◽  
Nickel Films

Catalytic reactions of anisole and deuterium on metal films

1966 ◽  
Vol 6 (1) ◽  
pp. 82-91 ◽  
Author(s):  
R.B. Anderson ◽  
C. Kemball
Keyword(s):  
Metal Films ◽  
Catalytic Reactions

The catalytic hydrogen reduction and deuterium exchange of cyclo pentanone on evaporated metal films and some observations on cyclo hexanone

1958 ◽  
Vol 246 (1247) ◽  
pp. 521-538 ◽  
Keyword(s):  
Hydrogen Reduction ◽  
Metal Films ◽  
Catalytic Reactions ◽  
Static System ◽  
Exchange Reactions ◽  
Cyclic Ketones ◽  
Reduction Processes ◽  
Similar Information ◽  
Catalytic Hydrogen ◽  
Palladium Platinum

Some catalytic reactions of cyclo pentanone vapour with hydrogen and with deuterium on evaporated metal films in a static system have been followed by means of a mass spectrometer. Hydrogenation to cyclo pentanol and hydrogenolysis with formation of cyclo pentane and cyclo pentene have been observed to different extents on films of rhodium, palladium, platinum, tungsten and nickel. Kinetic data, activation energies and frequency factors have been obtained for these reduction processes and possible mechanisms are discussed. Similar information has been obtained for the exchange reactions. An order of activity of the metals for inducing fission of the C—O bond is given. Preliminary experiments with cyclo hexanone have indicated an analogous behaviour to that found for cyclo pentanone. A comparison is drawn between the reactions of the cyclic ketones and those found for acetone (Stoddart & Kemball 1956; Kemball & Stoddart 1957).

Mechanical properties of vacuum-deposited metal films—II. Nickel films

1975 ◽  
Vol 23 (2) ◽  
pp. 187-192 ◽  
Author(s):  
C.A.O Henning ◽  
F.W Boswell ◽  
J.M Corbett
Keyword(s):  
Mechanical Properties ◽  
Metal Films ◽  
Nickel Films ◽  
Deposited Metal

scholarly journals Catalytic activity, crystal structure and adsorptive properties of evaporated metal films

1940 ◽  
Vol 177 (968) ◽  
pp. 62-90 ◽  
Keyword(s):  
Crystal Structure ◽  
Carbon Monoxide ◽  
Catalytic Activity ◽  
Hydrogen Adsorption ◽  
High Vacuum ◽  
Metal Films ◽  
Inert Gas ◽  
Unit Weight ◽  
Nickel Films ◽  
Oriented Films

Metal films of high and reproducible catalytic activity were obtained by condensation of their vapours on glass at any desired temperature. The catalytic activity was measured by the hydrogenation of ethylene. The crystal structure of these films was investigated by electron diffraction. By controlling the pressure of an inert gas (nitrogen, argon, etc.) during evaporation of the metals, unoriented and oriented films could be produced at will, and their catalytic activities were compared. Completely oriented nickel films were obtained with an inert gas pressure of 1 mm., the (110) plane, the least dense of the planes, lying parallel to the backing and the two remaining axes showing random distribution. Iron films were oriented with their (111) plane parallel to the backing, again the least dense plane thus oriented. Low-pressure adsorption bf hydrogen at room temperature and of carbon monoxide at liquid-air temperature revealed that the oriented gas-evaporated nickel films have twice the available surface per gram of randomly oriented high-vacuum films but ten times the activity. The oriented films have therefore fivefold the activity of unoriented films. Oriented films of an available surface equal to unoriented but of fivefold activity could also be obtained in high vacuum by evaporation on to oriented films previously produced by evaporation in an inert gas. The activity per unit weight of the films was constant, indicating ready accessibility to the interior of the film by the reacting gases. Adsorption of hydrogen was found to be immeasurably fast in all cases. Adsorption isotherms on nickel films were obtained for ethylene, carbon monoxide, nitrogen, hydrogen and oxygen; and the effect of catalyst poisoning by carbon monoxide and oxygen, as well as the effect of sintering, was studied. Loss of activity, decrease of hydrogen adsorption, and amount of poison were found to be proportional. The most extensive studies were made on nickel films, but films of iron, cobalt, palladium, platinum and copper were also investigated, and with the exception of copper similar results were obtained. The enhanced activity of oriented films appears to be associated with the larger distances in the (110) plane of nickel or the (111) plane of iron. The bearing of the results on the definition of active centres and on the general problem of adsorption is discussed.

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