Facile method for synthesis of nanosized β–MoO3 and their catalytic behavior for selective oxidation of methanol to formaldehyde

Thi Thuy Phuong Pham, Phuc Hoang Duy Nguyen, Tan Tai Vo, Huu Huy Phuc Nguyen and Cam Loc Luu

Abstract

β-MoO₃ was successfully synthesized from all commercial materials using a fast, effective and simple method and characterized by differential scanning calorimetry, x-ray powder diffraction, field emission scanning electron microscopy, infrared and Raman spectroscopy. The prepared sample was highly active and selective to formaldehyde formation from methanol over a wide range of reaction temperatures. β-MoO₃ catalyst also exhibited stable methanol conversion and formaldehyde selectivity at around 84% and over 95% respectively for over 15 operating hours at 320 °C. However, it may be deactivated at elevated reaction temperature due to transformation of metastable to stable phase. It was revealed that the prepared catalyst maintains its high selectivity to formaldehyde during deactivation. This can be considered as an advantage of the prepared MoO₃ catalyst in comparison with the industrial one