Method for treating a catalyst
AssigneeExxon Research & Engineering Co.
InventorShun C. Fung
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Abstract
A method for regenerating a Group VIII noble metal catalyst which has been contaminated with coke during a reforming process. The method comprises (a) burning off the coke from the catalyst, (b) redispersing the noble metal on the surface of the catalyst support by contacting the catalyst with halogen gas and carbon dioxide, and (c) chemically reducing the catalyst. The presence of carbon dioxide in the redispersing step improves the activity of the regenerated catalyst.
Claims16
A method of treating a Group VIII noble metal-containing catalyst selected from the group consisting of fresh catalysts and coke-contaminated catalysts comprising the steps of:
- (a) removing substantially all of the coke from said Group VIII noble metal-containing catalyst when said catalyst is a coke-contaminated catalyst;
- (b) redispersing the noble metal(s), the redispersion being carried out by contacting the Group VIII noble metal-containing catalyst in a reaction-vessel with a halogen or halide-containing gas with a source of oxygen present, and carbon dioxide, the amount of carbon dioxide being maintained at a partial pressure of at least 2 kPa in the reaction vessel substantially throughout the period in which the catalyst is in contact with the halogen or halide containing gas;
- (c) stabilizing the Group VIII noble metal-containing catalyst by treatment with an inert or oxygen containing gas;
- (d) substantially removing carbon dioxide and carbon monoxide so that the amount of carbon dioxide and carbon monoxide in the reaction vessel during the chemical reduction step (e) is less than 0.05 kPa partial pressure;
- (e) chemically reducing the Group VIII noble metal-containing catalyst.
Dependencies are inferred from the claim text.