Hydrogenation of Ethylene over PrCo5H2. 4

Open Access
Publisher Website
Google Scholar
Abstract
To elucidate the chemical reactivity of the hydrogen atom absorbed in the hydrogenated alloy PrCo51-1, 1, the hydrogenation of ethylene was carried out over PrCo5H2.4 in the absence (A) or presence ( B ) of hydrogen in gas phase. PrCo5112.4 was prepared from PrCo, according to an ordinary procedure with repeated heating and cooling in hydrogen atmosphere. The hydrogenation of ethylene was conducted at about 0°C in a conventional gas circulation system in a pressure range of ethylene 5--16 cmHg and of hydrogen 0--38.0 cmHg. The hydrogenation rate was followed by gas chromatography. In the case of (A), the total gas pressure in the gas phase remained constant during the reaction. The hydrogenation rate was independent of the partial pressure of ethylene and it increased in proportion to the concentration of the absorbed hydrogen atom. The rate of desorption of the absorbed hydrogen atom from PrCo5H2.4 also measured under a reduced pressure. The desorption rate was approximately the same as the hydrogenation rate under the similar conditions. From these results, it was concluded that the migration process of the absorbed hydrogen atom from the bulk of the alloy to its surface was rate-determining. In the case of (B ), on the other hand, the hydrogenation rate was accelerated by the gaseous hydrogen; the rate increased almost linearly with increasing pressure of hydrogen. The hydrogenatial of ethylene was also conducted over PrCo, under the similar conditions.

This publication has 0 references indexed in Scilit: