Copper hydrogenation

On the basis of information on the properties of the nickel-hydrogen and nickel-copper-hydrogen systems available in 1966 studies on the catalytic activity of nickel hydride as compared with nickel itself were undertaken. As test reactions the heterogeneous recombination of atomic hydrogen, the para-ortho conversion of hydrogen, and the hydrogenation of ethylene were chosen. 

Here is this procedure for the copper-hydrogen cell illustrated in Figure 19-14. We write the two half-reactions as Cu2+ aq, lbar) + 2e- Cu s) E° = 4-0.34 V... 

Copper, Hydrogen sulfide See Hydrogen sulfide Copper, Oxygen... 

The activity of the usual metallic hydrogenation catalysts (nickel, cobalt, palladium, and platinum) for the hydrogenation of ethylenic substances is impaired by carbon monoxide. Carbon monoxide also has been shown to inhibit the catalytic activity of a copper hydrogenation catalyst (Pease and Stewart, 6). 

Symbol of Sodium, Iron, Copper, Hydrogen, Oxygen, Chlorine, Platinum. 

The copper oxide has been reduced (loss of oxygen) to copper. Hydrogen has gained oxygen and so has been oxidised to water. To put it in more modern terms, the oxidation state of the copper has fallen from +2 to 0 and that of hydrogen has increased from 0 to +1. 

Copper. Hydrogen sulphide precipitates black copper sulphide in presence of dilute hydrochloric acid. Salts give green flame. Potassium ferrocyanide gives brown precipitate of copper ferrocyanide in presence of acetic acid. 

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