Hydrocarbons reforming on PtReS/Al2O3-Cl coked in a commercial reactor

QUERINI,C.A.; FIGOLI, N.S.; PARERA, J.M.

APPLIED CATALYSIS A-GENERAL

Año: 1989 vol. 52 p. 249 - 262

0926-860X

The deactivation of naphtha reforming catalyst under commercial conditions is very slow, and its study on the laboratory scale under similar operating conditions is impractical owing to the length of the experiments. For this reason, samples of coked catalyst withdrawn from a commercial reactor were catalytically tested with several model hydrocarbons (n-hexane, n-heptane and a mixture of n-pentane and cyclohexane). Changes in activity and selectivity due to the coke previously deposited and the selective poisoning of the acid function with n-butylamine were used to determine the contributions of catalytic functions. Samples taken a few days after the beginning of the commercial run showed that the metal function reaches a stationary state of constant activity for cyclohexane dehydrogenation and n-pentane hydrogenolysis. Temperature-programmed oxidation analysis showed that coke on the metal does not increase from that time. On the other hand, coke deposition on the acid function increases during the whole run. Poisoning by n-butylamine showed that the mechanism of n-heptane dehydrocyclization under commercial conditions is controlled by the acid function.