EP0048409A1
Expired / Lapsed
EP
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Reactivation of spent chromia-alumina catalyst by zinc oxide doping
Assignee: Air Products and Chemicals Inc
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Filing: 1981-09-10
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Granted: —
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Expires: 2001-09-10
Abstract
Abstract A method for the reactivation of aged chromia-alumina dehydrogenation catalyst which involves doping the aged catalyst with minor amounts of zinc oxide, preferably in the range of about 0.35% zinc oxide to 1.35% zinc oxide on the catalyst. The zinc oxide is added to the aged catalyst preferably by impregnation by immersion or spraying of a zinc nitrate solution, followed by drying and heat treating. Alternatively the zinc oxide addition can be accomplished by use of a volatile organic zinc compound added to the saturated feedstock and subsequent air regeneration of the catalyst in situ without removal of the catalyst from the reactor.
Inventors
- 👤 William Joseph Ambs
- 👤 Maurice Mcclellan Mitchell, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 21:03
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/16; B01J23/24; B01J23/26; B01J23/90; B01J23/92; B01J38/00; B01J38/48; B01J38/485
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
11 words
Reactivated chromia-alumina dehydrogenation catalyst comprising a minor amount of zinc oxide.
Claim 2
Dependent Claim
11 words
Reactivated chromia-alumina dehydrogenation catalyst comprising a minor amount of zinc oxide.
Claim 3
Dependent Claim
20 words
The reactivated chromia-alumina dehydrogenation catalyst of Claim 1 comprising from about 0.35% to about 1.35% by weight of zinc oxide.
Claim 4
Independent Claim
20 words
The method of reactivating aged.chromia-alumina dehydrogenation catalyst which comprises doping the aged catalyst with a minor amount of zinc oxide.
Claim 5
Independent Claim
20 words
The method of reactivating aged.chromia-alumina dehydrogenation catalyst which comprises doping the aged catalyst with a minor amount of zinc oxide.
Claim 6
Dependent Claim
56 words
The method of Claim 3 wherein the doping with zinc oxide is carried out by the steps of impregnating the aged chromia-alumina catalyst with an aqueous solution of zinc nitrate; drying the impregnated aged catalyst; and heat treating the dried catalyst at a temperature from about 700°F to about 1200°F in the presence of dry air.
Claim 7
Dependent Claim
39 words
The method of Claim 3 wherein the aged chromia-alumina catalyst is doped with zinc oxide in situ by the addition of a volatile organic zinc compound to the dehydrogenation reactor feedstream, followed by regeneration of the catalyst with air.
Claim 8
Dependent Claim
15 words
The method of Claim 5 wherein the volatile organic zinc compound is a dialkyl zinc.
Claim 9
Dependent Claim
25 words
The method of Claim 5 wherein the volatile organic zinc compound is selected from the group consisting of dimethyl zinc, diethyl zinc and d-iso-ipropyl zinc.
Claim 10
Dependent Claim
23 words
The method of Claim 5 wherein the volatile organic zinc compound is selected from the group consisting of zinc dimethoxide and zinc diethoxide.
References Cited (Backward Citations)
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