Synthesis, Characterization and Catalytic Activity of Nanocrystalline Ce2(MoO4)3/SiO2 as a Novel Catalyst for the Selective Production of Anhydrous Formaldehyde from Methanol

Abstract

In this paper, a series of catalysts of (0.5–10 wt%) Ce2(MoO4)3 supported on SiO2 gel were synthesized via a precipitation assisted impregnation method. The original and calcined catalysts were extensively characterized by TG-DTA, TEM, XRD, FTIR, N2 sorption analysis and acidity measurements. The catalytic activity successfully tested for the direct dehydrogenation of methanol into formaldehyde. Results revealed that, the complete conversion of methanol, with selectively of 100%, to formaldehyde was achieved at 350 °C and about 95% conversion obtained at 325 °C. In addition, a strong correlation between the catalytic activity and acidity was observed. Moreover, the moderate strength of Bronsted acid sites created on the surface of catalyst plays the main role in the production of formaldehyde. Finally, the catalyst exhibited a unique stability towards anhydrous formaldehyde formation up to a duration time of 200 h.