Structural characterization and dehydration activity of CeO2–SiO2 and CeO2–ZrO2 mixed oxides prepared by a rapid microwave-assisted combustion synthesis method

Catalytic performance of ceria–silica and ceria–zirconia mixed oxides for dehydration of 4-methylpentan-2-ol has been investigated. The reaction was carried out in the temperature region 523–673 K in a fixed-bed microreactor at normal atmospheric pressure. The investigated mixed oxides were prepared by a rapid microwave-assisted combustion synthesis method by using metal nitrates as precursors. X-ray diffraction (XRD), Raman spectroscopy (RS) and temperature programmed desorption (TPD) techniques were used to investigate the structural and surface properties of the mixed oxides. XRD studies revealed the formation of a specific Ce0.5Zr0.5O2 solid solution in case of ceria–zirconia sample, and the ceria–silica mixed oxide is found to be in amorphous form. RS measurements suggest the presence of oxygen vacancies and lattice defects in the ceria–zirconia mixed oxide sample. TPD of ammonia and CO2 results reveal that ceria–silica exhibits strong acid–base properties compared to ceria–zirconia mixed oxide. Good alcohol conversion and excellent 4-methylpent-1-ene selectivity were observed on both the mixed oxides.

CeO2–SiO2 and CeO2–ZrO2 mixed oxides synthesized by a rapid microwave-assisted solution combustion synthesis method were characterized and evaluated for vapor phase dehydration of 4-methylpentan-2-ol at normal atmospheric pressure. Both catalysts exhibited interesting catalytic properties for this reaction.Figure optionsDownload high-quality image (27 K)Download as PowerPoint slide