Propane oxydehydrogenation over transition metal modified zeolite ZSM-5 Original Research Article

Zeolite ZSM-5 of Si/Al ratio from 14 to 100, modified with transition metal ions (Fe3+, Mn2+, Co2+) introduced by means of ionic exchange, showed catalytic activity for propane oxidation already at 330 °C. The use of air as oxidant resulted mainly in carbon oxides, while application of N2O led to high selectivity towards propene. Thermal treatment of modified zeolites was a crucial parameter influencing an oxidative activity of the samples. High activity for propane oxydehydrogenation was found for samples calcined at 900 °C, while the calcination at lower temperature (600 °C) resulted in negligible propane conversion. Presence of MFI structure appeared indispensable for the formation of active transition metal complexes, while Si/Al ratio influenced activity and selectivity of catalysts less significantly.