A process for preparing a mixed metal oxide catalyst. The process includes the steps of admixing metal compounds, at least one of which is an oxygen containing compound, and at least one solvent to form a solution, removing the solvent from the solution to obtain a catalyst precursor, calcining the catalyst precursor at a temperature from about 350° C. to about 850° C. under a gaseous atmosphere comprising CO2, and forming a mixed-metal oxide catalyst. A process for reducing the formation of tellurium metal in a mixed metal oxide catalyst including tellurium is also provided.