Chromia water content

For illustrative purposes we give in Table II the water content of chromia as a function of pretreatment temperatures. In obtaining the results at the left, chromia packed in a tube was heated in hydrogen... 

Water Content of Chromia Pretreated at Different Temjieraturea... 

In order to substantiate this measure of chromia area, the rates of carbon monoxide oxidation over the various catalysts were measured. It was found that the alumina portion of the surface could be rendered inactive by selective poisoning with water and, under these conditions, the reaction was catalyzed exclusively by the ehromia surface. Since the activation energy was independent of the chromium content, it was reasonable to expect a linear variation of specific activity (i.e., activity per unit total surface area) with the fraction 0 (Table I) of the total surface contributed by the chromia phase. In Fig. 3 the specific rate is... 

More recently O Reilly and Poole 121) have measured the spin-lattice (Tj) and spin-spin T relaxation times of the hydrogen nuclei in a monolayer of water physically adsorbed on the same reduced, impregnated chromia-alumina catalysts used in the AP NMR studies discussed above. The variations of these two relaxation times with chromium content are shown in Fig. 25. It will be noticed that both... 

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