Synthesis and characterization of ZrO2 as an acid–base catalyst Dehydration–dehydrogenation of propan-2-ol

Abstract

Two ZrO ₂ -based catalysts have been synthesized by thermal treatment of a gel prepared from ZrOCl ₂ ·8H ₂ O. The effect of different preparation parameters on the final properties of the solids was studied. Textural characterization was carried out from nitrogen adsorption–desorption isotherms. XRD and FT-Raman spectroscopy have been used to elucidate the physical state of the catalysts. Their acid–base properties were studied by using temperature-programmed desorption–mass spectrometry (TPD–MS) and diffuse reflectance FTIR techniques (DRIFT), employing pyridine, 2,6-dimethylpyridine and carbon dioxide as probe molecules. Both solids were tested for the dehydration–dehydrogenation of propan-2-ol. The reactivity of the catalysts was studied through isotherm and temperature–programmed surface reactions (TPSR), in a flow reactor. In addition, temperature–programmed oxidation (TPO) and temperature–programmed desorption (TPD) experiments revealed that catalyst deactivation was caused by carbon deposition and irreversible adsorption of propene formed on the catalytic surface.