The total oxidation of propane over supported Cu and Ce oxides: A comparison of single and binary metal oxides

摘要

The total oxidation of propane is studied by means of steady-state experiments over a set of Cu- and Ce-based catalysts at a propane inlet partial pressure of 0.6 kPa, an oxygen partial pressure of 3.5 kPa and temperatures from 595 to 648 K. The catalysts were characterized by inductively coupled plasma (ICP), Brunauer-Emmett-Teller specific surface area (BET), temperature- programmed desorption (TPD), X-ray diffraction (XRD), pulse reduction- reoxidation, and H_2- and C_3H_8-temperature- programmed reduction (TPR). A synergistic effect between cupric oxide, CuO, and ceria, CeO_2, is observed using a Mars-van Krevelen model to describe the kinetic data: the activation energies for reduction and reoxidation, obtained on the binary metal oxide catalyst with both cupric oxide and ceria, are 20 kJ mol~(-1) lower than those obtained on the single Cu- or Ce-based catalysts. The corresponding turnover frequencies are the highest.