Regenerated mixed metal oxide catalysts

摘要

A mixed metal oxide, which may be an orthorhombic phase material, is regenerated, selectively enriched or selectively poisoned as a catalyst to reduce catalyst aging for the production of unsaturated carboxylic acids, or unsaturated nitriles, from alkanes, or mixtures of alkanes and alkenes. Regeneration is effected by contacting said mixed metal oxide with a an oxidizing gas such as oxygen, air, steam and combinations thereof in a regenerator at a temperature of from 300°C to 600°C to form said regenerated catalyst.
The catalyst is enriched by re-metallizing the mixed metal oxide using a volatile organometallic compound.
Catalyst lifetime is extended by reversing flow direction of reactants.