Chemisorption of thiophenes

Verna (62) studied the dissociative adsorption of thiophene on platinum, palladium, and rhodium dispersed on alumina. Figure 7 and Table II present the dissociative chemisorption of thiophene to butane on the three metals. The sulfur coverage of platinum is very low compared to the other metals. The sulfur coverage on palladium is about 2.5 times higher than on platinum such a value is similar to the one found by Mathieu and Primet (63). 

Fig. 7. Formation of butane as a function of time, during the dissociative chemisorption of thiophene on different metals.

Boitiaux et al. and Verna (61, 62) studied the dissociative chemisorption of thiophene in the presence of isoprene and of the corresponding methyl-butenes on palladium. Figure 8 records the results of a typical experiment carried out with a mixture of thiophene and 3 mol% isoprene in heptane. The evolution of isoprene, isopentenes, and isopentane is shown as a... 

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