Influence of Cr/Zr Ratio on Activity of Cr–Zr Oxide Catalysts in Non-Oxidative Propane Dehydrogenation

Abstract

Two series of chromium–zirconium mixed oxide catalysts with different Cr/Zr molar ratio are prepared by co-precipitation method. Porous structure of the catalysts is studied by low-temperature N2 adsorption–desorption. Phase composition and chromium states in the catalysts are characterized by X-ray diffraction (XRD), UV-visible spectroscopy, and temperature-programmed reduction with hydrogen (TPR-H2). The mixed catalysts are tested in non-oxidative dehydrogenation of propane at 550 °C. The catalysts synthesized without ageing of precipitate show higher activity in propane dehydrogenation due to the higher content of reducible Cr+5/+6 species due to its stabilization on the ZrO2 surface.

Keywords

• chromia catalysts
• mixed oxides
• zirconia
• dehydrogenation of propane