Thermodynamic Calculations to Determine the Optimal Composition of Oxide Catalysts

Abstract

Thermodynamic calculations of the optimal compositions of oxide catalysts with different natures are performed based on the theory of catalysis by polyhedra. The obtained compositions of the active catalysts agree with experimental data. The electrostatic potential generated by polyhedra of metal-oxide catalysts in a variety of directions is calculated. The dependence of the sign and magnitude of the potential on the distance from the central metal ion towards the vertex of the polyhedron, the middle of its edge or the centre of the face is estimated. It is assumed that the magnitude of the potential can serve as a reference point for determining active centres, which produce adsorption complexes and intermediate compounds.

Keywords: catalysts; electrostatic potential; polyhedron; theory of catalysis by polyhedra; thermodynamic calculations.