Model bulk Mo–V–Te–O catalysts for selective oxidation of propane to acrylic acid

Abstract

The crystal structures and chemical compositions of the M1 and M2 phases proposed as active and selective in propane oxidation to acrylic acid over the bulk mixed Mo–V–Te–O catalysts were investigated by the transmission electron microscopy, coupled with energy dispersive analysis of X-rays. The results revealed that the crystal structure of the M1 phase is orthorhombic with space group Pbca, lattice parameters a=21.25 Å, b=27.14 Å, c=4.03 Å and composition Mo 0.64V 0.32Te 0.1O 3.05 (Mo/V ∼2), whereas M2 is hexagonal with space group P6mm, lattice parameters a=7.10 Å, c=4.05 Å and composition Mo 1.79V 1.85Te 0.1O 11.36 (Mo/V ∼1). The M1 phase was dominant in the Mo–V–Te–O catalyst. The results obtained indicated that the bulk Mo–V–Te oxides represent a well-defined model catalytic system for the studies of the surface molecular structure-activity/selectivity relationships in propane oxidation to acrylic acid.