In situ determination of hydrogen inside a catalytic reactor using prompt gamma activation analysis.

Prompt gamma activation analysis (PGAA) has been further developed to analyze reacting components inside a chemical reactor. The new method, in situ PGAA, was used to determine the hydrogen-to-palladium molar ratio under various conditions of palladium-catalyzed alkyne hydrogenation. The H/Pd molar ratio was successfully measured in the range of 0.

The roles of subsurface carbon and hydrogen in palladium-catalyzed alkyne hydrogenation.

Alkynes can be selectively hydrogenated into alkenes on solid palladium catalysts. This process requires a strong modification of the near-surface region of palladium, in which carbon (from fragmented feed molecules) occupies interstitial lattice sites. In situ x-ray photoelectron spectroscopic measurements under reaction conditions indicated that much less carbon was dissolved in palladium during unselective, total hydrogenation.