Acid and base properties of molybdophosphoric acid supported on zirconia: Characterized by IR spectroscopy, TPD and catalytic activity

Solid acid catalysts of 12-molybdophosphoric acid (MoP) supported on hydrous zirconia were synthesized using the impregnation method. The solids were characterized by: N2 adsorption to determine specific surface area and pore size distribution, Thermo-Programmed Desorption (TPD) of NH3 and CO2 were employed for the study of acid and base properties, Raman spectroscopy was used to study the MoP structure, along with 31P Nuclear Magnetic Resonance and X-ray Photoelectron Spectroscopy. These techniques showed that the heteropolyacid presented intact Keggin structure. The activity of MoP/Z catalysts was measured in the 4-methylpentan-2-ol decomposition. The selectivity to the different products was due to the acid base properties of the samples. 4-methylpentan-2-one product was obtained at low concentration of MoP on ZrO2.

► xMoP/Z catalysts were studied by combination of Raman, XPS and 31P-NMR techniques.
► The acid and base properties of catalysts were studied by TPD of NH3 and CO2.
► The properties of catalysts were evaluated in the reaction of 4-methylpentan-2-ol.
► MIBK was obtained at low concentration of MoP.
► The catalysts provided excellent selectivity to olefins.