Heterogeneous catalysis ethylene/ethane

Volpe, A. F., Weinberg, W. H., Woo, L., Zysk, J., Combinatorial heterogeneous catalysis oxidative dehydrogenation of ethane to ethylene, selective oxidation of ethane to acetic acid, and selective ammonoxidation of propane to acrylonitrile, Top. Catal. 2003, 23, 65-79. 

In heterogeneous catalysis the catalyst is present as a phase distinct from the reaction mixture. The most important case is the catalytic action of certain solid surfaces on gas-phase and solution-phase reactions. A critical step in the production of sulfuric acid relies on a solid oxide of vanadium (V2O5) as catalyst. Many other solid catalysts are used in industrial processes. One of the best studied is the addition of hydrogen to ethylene to form ethane ... 

Hydrogenation reactions are reactions in w hich hydrogen is added to some compound, particularly unsaturated organic compounds. A large number of reactions of this type are of commercial importance, and almost all of them are catalyzed by either a soHd catalyst (heterogeneous catalysis) or some catalyst in solution (homogeneous catalysis). One of the simplest reactions of this type is the hydrogenation of ethylene to produce ethane. 

The reaction of hydrogen gas with ethylene gas to form ethane gas provides an example of heterogeneous catalysis ... 

A very important organic example of heterogeneous catalysis is hydrogenation, the addition of H2 to C=C bonds to form C—C bonds. The petroleum, plastics, and food industries employ this process on an enormous scale. The conversion of vegetable oil into margarine is one example. The simplest hydrogenation converts ethylene (ethene) to ethane ... 

I shall describe an example of heterogeneous catalysis first. Let s suppose you want to use hydrogen to react with ethene, CH2=CH2 (ethylene, i), to produce ethane, CH3-CH3, 2. There are more useful things to do with ethene than turning it into rather useless ethane, such as using it to make polyethylene (Reaction 13), but this example... 

Hydroformylation of ethylene was catalyzed by the cluster anion [Ru5G(GO)i6Me] , supported on a highly dehydrated silica (823 K). The catalysis was nearly 100% selective at 398 K. The retention of the cluster framework under the reaction conditions was shown by extended X-ray adsorption fine-structure curve fitting. The cluster anion does not catalyze this reaction in homogeneous solution, and a heterogeneous Ru-SiOz catalyst prepared by conventional methods gave ethane rather than propanal. "... 

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