Method for improving a vanadium based mixed metal oxide catalyst by treating it with a liquid, the catalyst thereby obtainable and its use in oxidation and ammoxidation reactions

摘要

A mixed metal oxide of Mo,V, Te and Nb, which may be an orthorhombic phase material, is improved as a catalyst for the production of unsaturated carboxylic acids, or unsaturated nitriles, from alkanes, or mixtures of alkanes and alkenes, by contact with a liquid contacting member selected from the group consisting of organic acids, alcohols, inorganic acids and hydrogen peroxide, preferably oxalic acid.