Role of Crystalline Structure in Allyl Alcohol Selective Oxidation over Mo3VOx Complex Metal Oxide Catalysts

Abstract

The role of the crystalline phase of Mo3VOx in the catalytic oxidation of allyl alcohol over four kinds of crystalline (orthorhombic, trigonal, tetragonal, amorphous) Mo3VOx catalysts was investigated to determine the active sites for the reactions. Tetragonal Mo3VOx was found less active for the formation of acrylic acid from allyl alcohol, although acrolein was obtained selectively at higher temperature. For orthorhombic and trigonal Mo3VOx catalyst, allyl alcohol converted to acrolein and propanal competitively at the mouth of the heptagonal channel over the a–b plane of the rod-type crystalline particles, and these aldehydes were oxidized consecutively to acrylic acid. Acrylic acid was formed effectively at increased reaction temperature over orthorhombic, trigonal and amorphous Mo3VOx catalysts, and the maximum yields of acrylic acid were 73 % for the orthorhombic Mo3VOx catalyst and 72 % for the trigonal Mo3VOx catalyst at 350 °C.