Catalytic Study of the Partial Oxidation Reaction of Methanol to Formaldehyde in the Vapor Phase

Abstract

In the present work, several parameters affecting on the catalytic behavior were studied in the process of partial oxidation of methanol to formaldehyde, such as: Mo/Fe ratio in unsupported catalysts, weight percent of the metallic phase in the supported catalysts, the effect of different supports, the method of Mo-Fe deposition on the supports, and the stability of the prepared catalysts against coke. These catalysts were characterized by X-ray diffraction (XRD), Fourier Transform Infra Red (FT-IR), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), N2 adsorption-desorption, and Atomic Adsorption Spectroscopy (AAS) methods. The best results (the methanol conversion = 97 % and formaldehyde selectivity = 96 %) were obtained for Mo-Fe/γ-Al2O3 prepared by co-precipitation method with Mo/Fe = 1.7, 50 wt.% of Fe-Mo phase, 2 mL/h methanol flow rate, and 120 mL/min air flow rate at 350 oC.