Hydrogen by palladium

Alloying elements exert a very important influence upon the occlusion of hydrogen by palladium. The absorptive power of commercial palladium is from 10 to 20 per cent, less than that of the pure metal, a fact that is attributed to the presence of small quantities of platinum and ruthenium.6... 

This theory of a mechanical absorption of hydrogen by palladium receives support from the researches of Hoitsema,4 who studied the... 

The heat evolved on the occlusion of hydrogen by palladium black is nearly the same as that evolved by platinum black under similar conditions. The heat of occlusion remains constant for the different fractions of hydrogen occluded, namely, 4640 calories per gram of hydrogen, or 4370 calories if the external work done by the atmosphere is allowed for.1... 

Hoitsema1 has demonstrated the reversibility of the occlusion of hydrogen by palladium, and examined the influence exerted by pressure. He found that at low pressures the concentration of the hydrogen in the metal is proportional to the square root of the pressure. The results of his experiments, carried out at 100° C., can be tabulated thus ... 

The occlusion of hydrogen by palladium decreases very rapidly with rise of temperature from 100° to 600° C., more slowly up to 800° C., and only very slightly between 800° and 1500° C.3... 

The existence of a dissociation tension does not always prove the existence of a ilefinite compound. Dissociation of palladium hydride.— The absence of a fixed dissociation allows also, in certain cases, to demonstrate that a body is not a definite compound prudence must be exercised in concluding from the existence of a fixed dissociation tension the existence of a definite compound the study of the absorption of hydrogen by palladium will show us that such a conclusion must sometimes be accepted with caution. 

During the Oxidation of Hydrogen by Palladium. Chem. Eng. Commun. 7(6) 335-343... 

Absorption of a gas by a solid for example, the occlusion of hydrogen by palladium. 

Burch R., Buss R.G. (1975), Absorption of hydrogen by palladium-copper alloys ,/. Chem. Soc, Faraday Trans. 1,71,913-921. 

The first report on the reaction of hydrogen with a metal dates from 1866, when Graham observed the absorption of hydrogen by palladium up to 935 times its own volume. 

Wunder RW, Cobes JW, Phillips J, Radovic LR, Lopez-Peinado AJ, Carrasco-Marin F. Microcalorimetric study of the adsorption of hydrogen by palladium powders and carbon-supported palladium particles. Langmuir 1993 9 984-992. 

Another example of reactions in which M MF catalysts exhibit exiting properties is the very selective olefin hydrogenation by palladium nanoparticles supported on magnesium fluoride phase. Transmission electron microscope (TEM) micrographs in Figure 6.14 display that the majority of Pd particles are approximately 5 nm in diameter, although the particle size distribution spreads up to 20 nm. These catalysts showed extremely high metal dispersion compared with examples reported in literature [73]. 

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