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Kinetic Parameters for the Selective Hydrogenation of Acetylene on GaPd 2 and GaPd
Author(s) -
Zimmermann René R.,
Hahn Tobias,
Reschetilowski Wladimir,
Armbrüster Marc
Publication year - 2017
Publication title -
chemphyschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.016
H-Index - 140
eISSN - 1439-7641
pISSN - 1439-4235
DOI - 10.1002/cphc.201700535
Subject(s) - acetylene , intermetallic , catalysis , ethylene , kinetics , activation energy , chemistry , selectivity , thermodynamics , chemical kinetics , kinetic energy , order of reaction , materials science , organic chemistry , reaction rate constant , physics , alloy , quantum mechanics
Intermetallic GaPd 2 is a highly selective and stable catalyst for the semi‐hydrogenation of acetylene. Knowledge of the underlying reaction kinetics is essential to gain a deeper understanding of the selective hydrogenation on this catalytic material. To date, there has been no experimental kinetic data published for this reaction on a well‐defined intermetallic catalyst possessing isolated active sites. Kinetic measurements are performed at 140–200 °C, revealing an apparent activation energy of 29(2) kJ mol −1 . GaPd 2 is shown to be the first binary catalyst material, which shows a positive reaction order (0.89) with respect to acetylene at 200 °C. The influences on the extent of acetylene conversion, specific activity and selectivity to ethylene, ethane, and higher hydrocarbons are determined by a 2 4 factorial experiment following a design of experiments approach. Temperature and pressure have the strongest impact on these values. The results allow optimal operation for achieving high ethylene yields. A comparison of the reaction kinetics on GaPd 2 with experimental results obtained for GaPd reveals different orders of reaction of H 2 and C 2 H 2 on the two compounds.