Home | english  | Impressum | Sitemap | KIT

Kinetics and particle size effects in ethene hydrogenation over supported palladium catalysts at atmospheric pressure

Kinetics and particle size effects in ethene hydrogenation over supported palladium catalysts at atmospheric pressure
Autor:

A. Binder, M. Seipenbusch, M. Muhler, G. Kasper

Quelle:

Journal of Catalysis, 2009, 268 (1), 150-155

Palladium catalysts were synthesized in a highly controlled chemical vapor deposition process, giving narrowly distributed Pd nanoparticles with median sizes ranging from 1.3 to 5 nm on a SiO2 or TiO2 support. Unsupported Pd nanoparticles with median sizes between 3 and 9 nm were also generated by spark discharge.
The influence of Pd particle size and support on the hydrogenation of ethene to ethane was investigated in a fixed-bed flow reactor at atmospheric pressure. The TOF was found to peak at 3 to 4 nm with a weak dependence on the support material. Metal support interactions were generally weak, indicated by closely matching activation energies of 20 kJ mol−1 for unsupported Pd, and 28 kJ mol−1 for titania and silica supported catalysts. Peak TOF values varied systematically with H2 partial pressure, indicating a pronounced volume effect of the Pd particles on the reactivity.