Fast Dehydrogenation Kinetics of Perhydro-N-propylcarbazole over a Supported Pd Catalyst

We report a kinetic study on dehydrogenation of perhydro-N-propylcarbazole over a supported Pd catalyst in the temperature range of 160–200 °C at 101 kPa. The dehydrogenation process was found to undergo three consecutive stages: perhydro-N-propylcarbazole → octahydro-N-propylcarbazole → tetrahydro-N-propylcarbazole → N-propylcarbazole. Detailed kinetics of all three stages was explored and the data were fitted well to a first-order reaction with the estimated apparent activation energies of the elementary steps of 90.0 kJ/mol, 90.6 and 96.4 kJ/mol, respectively. Full dehydrogenation of perhydro-N-propylcarbazole was achieved within 240 min at 200 °C with moderate kinetics under our experimental conditions.