Cr-doped mesoporous M1 phase MoVTeNbOx catalyze selective oxidation of propane to acrylic acid

Abstract

Abstract In this work, we investigated the doping of MoVTeNbOx catalysts with a small amount of Cr using spray drying. The effect of Cr doping on their crystalline phase structure, physicochemical properties, and catalytic propane oxidation to acrylic acid performance was investigated. The results showed that the catalyst samples were prepared by spray drying from rod stacking into unique spherical shapes. In addition, Cr doping induced a change in the mesopore structure formed by rod stacking, reducing the pore radius of the catalysts from 5–10 nm to 2–4 nm. Meanwhile, Cr doping dramatically reduced the average particle size of the motivations, decreasing the rod cross-sectional area of the catalysts from 234.21 nm to 134.96 nm and the rod length from 1.096 µm to 485.71 nm, which significantly increased the number of (001) active crystalline surfaces. Not only that, Cr doping increased the V5+ content on the catalyst surface from 35.8–72.6%. Together with the mesoporous structure, the Cr-doped MoVTeNbOx showed excellent performance in catalyzing the propane-selective acrylic acid production reaction. Among them, the S-3 sample (V: Cr = 1:0.015) increased the selectivity of acrylic acid from 67.5–84.3% and the acrylic acid yield from 26.4–43.2% when the reaction temperature was 380°C.