Ammoxidation process with external catalyst regeneration zone
AssigneeUop LLC
InventorPeter R. Pujado
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Abstract
A process for the ammoxidation of alkylaromatic hydrocarbons in a fluidized bed reactor is disclosed. A relatively small stream of catalyst is removed from an unsegregated single catalyst bed within the reaction zone and passed into a regeneration zone operated at a higher temperature. Metals on the catalyst are oxidized by contact in the regeneration zone with a preheated oxygen containing gas stream, which is then passed into the reaction zone. The residual oxygen in this gas stream may supply 15 percent or more of the oxygen consumed in the reaction zone. The continuous regeneration maintains the metals on the catalyst in a high oxidation state.
Claims13
A process for the ammoxidation of alkylaromatic hydrocarbons which comprises the steps of:
- (a) passing a feed stream which comprises an alkyl-aromatic hydrocarbon into the lower one-half of a reaction zone which is maintained at ammoxidation conditions including a temperature of between 350.degree. C. and 550.degree. C. and which contains a fluidized bed of catalyst;
- (b) passing a first oxygen-containing stream and ammonia into the lower one-half of the reaction zone;
- (c) removing from the reaction zone an effluent comprising an aromatic nitrile and recovering the aromatic nitrile;
- (d) transferring a stream of used catalyst from the reaction zone into an isolated regeneration zone which is maintained at catalyst oxidation conditions including a temperature between 350.degree. C. and 550.degree. C. and which contains a fluidized bed of catalyst;
- (e) heating a second oxygen-containing stream to a temperature above 350.degree. C. and passing the second air stream into the regeneration zone;
- (f) removing from the regeneration zone a regeneration zone effluent stream which comprises at least 10 mole percent oxygen and passing the regeneration zone effluent stream into the reaction zone as a third oxygen-containing vapor stream which supplies at least 8 mole percent of the total oxygen consumed within the reaction zone;
- and,
- (g) transferring a stream of regenerated catalyst from the regeneration zone to the reaction zone.
Dependencies are inferred from the claim text.