Oxidative dehydrogenation of ethane to ethylene was investigated over Chromia and Cr-V mixed oxide catalysts synthesized following a complexation procedure. With an O2/C2H6 feed ratio of 0.17, Chromia exhibited a total conversion value of about 0.20 at 447°C (at a space time of 0.24 s.g/mL) with an ethylene selectivity of 0.82. Chromia catalyst was more active than Cr-V mixed oxide at temperatures as low as 200°C. Pulse-response experiments carried out with ethane pulses injected into O2-He indicated the presence of at least two different sites for the formation of CO2 and H2O over Chromia catalyst. In the dynamic experiments carried out with the Cr-V mixed oxide catalyst and by injecting O2 pulses into a gas stream containing a mixture of C2H6 and He, formation of CO rather than C2H4 was favored. Results of the dynamic runs carried out without gas phase oxygen strengthened the conclusion of lattice oxygen participation in the selective oxidation of ethane reaction through a redox mechanism.
Highly selective production of styrene by non-oxidative dehydrogenation of ethylbenzene over molybdenum-zirconium mixed oxide catalyst in fixed bed reactor: Activity, stability and kinetics
