Kinetics of nn-dodecane dehydrogenation on promoted platinum catalyst

Kinetics of nn-dodecane dehydrogenation over a promoted Pt–Sn–/Al2O3Al2O3 catalyst between 733 and 763 K were determined. The reaction scheme includes three consecutive dehydrogenation reactions and also cracking of olefins to light paraffins. Various rate models based on Langmuir–Hinshelwood–Hougen–Watson (LHHW) and Eley Rideal mechanisms were derived for the three dehydrogenation reactions and subjected to model discrimination and parameter estimation by using Box's complex optimisation method. Of the 12 different models tested, model based on LHHW mechanism with surface reaction as rate-determining step fitted the experimental data well. The estimated rate constants of the best model are thermodynamically sound and statistically consistent.