Structural and textural effects of TeO2 added to MoO3

Morphological and microstructural characterization of the MoO3-TeO2 system has shown interparticle cementation of MoO3 agglomerates by Te2MoO7 and second phase deposition along the cleavage planes in MoO3 crystallites. The main morphological parameters of the binary system reflect the behaviour of the liquidus curve in the phase diagram. The size and shape of the component grains in the solid were determined. The porosity of the grains diminishes with increasing mobility of the matter during activation. Intergranular embrittlement of the solid and brittle fracture of MoO3 crystallites due to oxygen depletion during reduction were examined by optical microscopy. The results are discussed in relation to the use of the MoO3-TeO2 system in oxidation catalysis.