Process for improving activity of tellurium containing metal oxide catalysts

摘要

A process for improving the activity of tellurium containing metal oxide catalysts useful as catalysts for oxidation, ammoxidation or oxidative dehydrogenation of organic compounds by heating the catalysts together with an activity-improving agent to a temperature up to about 900 DEG C. in a gaseous atmosphere. The process can be effectively applied to deteriorated or spent catalysts, the activity of which has been deteriorated due to use for a long period of time. The activity improviding agent is selected from the group consisting of (i) a tellurium-molybdenum compound unsupported or supported on an inert carrier; (ii) a dry mixture of a tellurium compound and a molybdenum containing material selected from the group consisting of a molybdenum compound, a molybdenum enriched catalyst and a molybdenum compound supported on an inert carrier; (iii) a dry mixture of a tellurium enriched catalyst and a molybdenum compound unsupported or supported on an inert carrier; and (iv) a dry mixture of a tellurium compound supported on an inert carrier and a molybdenum containing material selected from the group consisting of a molybdenum compound, a molybdenum enriched catalyst and a molybdenum compound supported on an inert carrier. In a particularly preferred embodiment, the process according to the present invention can be carried out by contacting the tellurium containing metal oxide catalysts with the activity-improving agent in a fluidized-bed. More preferably, the contact is carried out during the oxidation, ammoxidation or oxidative hydrogenation reaction.