Selective Oxidation of Methanol to Dimethoxymethane at Low Temperatures through Size‐controlled VTiOx Nanoparticles

Abstract

AbstractA vanadium/titanium mixed‐oxide catalyst with a narrow particle‐size distribution, large BET surface area, high dispersion of vanadium, and enhanced acidity and redox capabilities was prepared by a cetyltrimethylammonium bromide (CTAB) surfactant‐associated vanadium oxide and titanium oxide co‐precipitation route. The impact of the CTAB content on the catalyst properties, including structure, chemical states, and acidity and redox activities, was investigated by X‐ray diffraction, BET surface area, high‐resolution transmission electron microscopy, energy‐dispersive X‐ray spectroscopy, X‐ray photoelectron spectroscopy, Raman spectroscopy, H2 temperature‐programmed reduction, and temperature‐programmed desorption of ammonia. Relative to the catalyst prepared without CTAB, the resultant catalyst exhibited significantly improved low‐temperature activity for the oxidation of methanol to dimethoxymethane (DMM). A maximum methanol conversion of 53 % with 93 % selectivity to DMM were achieved over the VTiS–CTAB catalyst at 120 °C, and this optimized reaction temperature is 25 °C lower than that needed for the reference catalysts and the yield of DMM is comparable.