Cyclohexanes, catalytic reactions with platinum catalysts

Isomerization. Isomerization is a catalytic process which converts normal paraffins to isoparaffins. The feed is usually light virgin naphtha and the catalyst platinum on an alumina or zeoflte base. Octanes may be increased by over 30 numbers when normal pentane and normal hexane are isomerized. Another beneficial reaction that occurs is that any benzene in the feed is converted to cyclohexane. Although isomerization produces high quahty blendstocks, it is also used to produce feeds for alkylation and etherification processes. Normal butane, which is generally in excess in the refinery slate because of RVP concerns, can be isomerized and then converted to alkylate or to methyl tert-huty ether (MTBE) with a small increase in octane and a large decrease in RVP. 

Third, the doublet and, especially, sextet models require very precise superimposing of the molecule on the catalyst lattice. We have found that the cyclohexane derivatives, in accordance with the sextet model, smoothly dehydrogenate only on the following metals nickel, cobalt, iridium, palladium, platinum, ruthenium, osmium, and rhenium, all of which crystallize in Al, A3 lattices with certain interatomic distances. These results extend to the alloys of these metals. The catalytic activity of rhenium for this reaction was predicted by the multiplet theory as this metal maintains the square of activity this prediction was realized experimentally in the laboratory of the author. Similar correlations take place in the exchange of cyclanes with deuterium. 

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