§
Luxuse
Patent Intelligence
Sign In
← Back to Patent Explorer
US3962285A Expired / Lapsed US ⏱️ 0.0 years remaining

Olefin oxidation process

Assignee: ExxonMobil Technology and Engineering Co
•
Filing: 1974-05-22
•
Granted: 1976-06-08
•
Expires: 1994-05-22
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The instant invention relates to a process for oxidizing olefins to their corresponding epoxides by contacting said olefin with oxygen in the presence of a multimetallic condition at oxidation conditions. Preferably, this process is utilized to oxidize ethylene to ethylene oxide by contacting ethylene in the presence of oxygen with a silver catalyst promoted by one or more metals combined with silver in an alloy. The promoter metals are selected from the group consisting of platinum, rhenium, palladium, ruthenium, iron, copper, and gold. Preferably, the catalysts used in the process of the instant invention are bimetallic catalysts comprising silver in combination with a promoter metal selected from the group consisting of palladium, ruthenium or rhenium, preferably rhenium and ruthenium, and most preferably rhenium. The catalysts are prepared by contacting a silver salt or silver oxide having a surface area of from 20-40 M 2 /gm with a solution containing a decomposable salt of said promoter metal, at impregnating conditions, drying said impregnated salt and activating said dried impregnated silver oxide or silver salt by contacting with a reducing environment, preferably hydrogen at a temperature of from 100° to 500°C, more preferably from 150° to 300°C. Catalysts prepared in this manner are characterized as comprising a bulk phase of substantially pure silver and a surface alloy phase of silver and said promoter metal.

Inventors

  • 👤 James A. Cusumano

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 17:07
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/38; B01J23/54; B01J23/66; B01J23/68; B01J23/688; B01J23/48; B01J23/50; B01J23/70; B01J23/89; B01J23/8926; B01J23/8933; B01J23/8946

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 127 words
A process for oxidizing ethylene to ethylene oxide which comprises contacting said ethylene, in the presence of oxygen, under oxidation conditions, such oxidation conditions comprising mixing about 20 to 40 wt. % oxygen, about 5 to 20 wt. % ethylene and about 40 to 75 wt. % of an inert gas at a temperature of from 100° to 400°C and a pressure of from 1 to 20 atm with a bimetallic catalyst, said catalyst comprising from 90 to 99.9 wt. % of silver and from 0.1 to 10 wt. % of a promoter metal present as a surface alloy phase which promoter metal is rhenium, at a space velocity of 1000 to 4000 V/V/hr. and thereby converting at least a portion of the ethylene to ethylene oxide.
Claim 2
Dependent Claim 127 words
A process for oxidizing ethylene to ethylene oxide which comprises contacting said ethylene, in the presence of oxygen, under oxidation conditions, such oxidation conditions comprising mixing about 20 to 40 wt. % oxygen, about 5 to 20 wt. % ethylene and about 40 to 75 wt. % of an inert gas at a temperature of from 100° to 400°C and a pressure of from 1 to 20 atm with a bimetallic catalyst, said catalyst comprising from 90 to 99.9 wt. % of silver and from 0.1 to 10 wt. % of a promoter metal present as a surface alloy phase which promoter metal is rhenium, at a space velocity of 1000 to 4000 V/V/hr. and thereby converting at least a portion of the ethylene to ethylene oxide.
Claim 3
Dependent Claim 11 words
The process of claim 1 wherein said inert gas is nitrogen.
Claim 4
Dependent Claim 11 words
The process of claim 1 wherein said inert gas is helium.
Claim 5
Dependent Claim 20 words
The process of claim 1 wherein said catalyst has a surface area of from 0.1 to 30 meters 2 /gm.
Claim 6
Dependent Claim 144 words
The process of claim 4 wherein said catalyst is prepared by impregnating by the incipient wetness technique silver oxide having a surface area of from 20 to 40 meter 2 /gram or a salt of silver selected from the group consisting of silver carbonate, silver halides and silver carboxylates having from 1-10 carbon atoms with a solution of a rhenium salt at conditions whereby said silver oxide or said silver salt is impregnated with said rhenium salt solution, drying said impregnated silver oxide or said silver salt at from about 50°-100°C and reducing said dried impregnated silver oxide or the silver salt at a temperature of from 100° to 500°C in a reducing atmosphere to activate said catalyst, thereby yielding a catalyst wherein the silver component ranges from 90 to 99.9 wt. % and the rhenium component ranges from 10 to 0.1 wt. %.
Claim 7
Dependent Claim 48 words
The process of claim 5 wherein the desired promoter metal salt impregnated silver oxide or silver salt is reduced in a hydrogen atmosphere which hydrogen atmosphere is passed over the catalyst at from 5 to 25 liters/hr./gm. of catalyst at a temperature of from about 100°-500°C, preferably 150°-300°C.
Claim 8
Dependent Claim 13 words
The process of claim 6 wherein said catalyst is prepared from silver oxide.
Claim 9
Dependent Claim 26 words
The process of claim 5 wherein the silver salt is a water insoluble silver salt and the solution of a rhenium salt is an aqueous solution.
Claim 10
Dependent Claim 21 words
The process of claim 5 wherein the rhenium salt is selected from the group consisting of rhenium chlorides and rhenium nitrates.

References Cited (Backward Citations)

US2404438A Cited
GB811828A Cited
US3775346A Cited
US3664970A Cited
US3844981A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-06-08 1979-12-08 1980-06-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-06-08 1983-12-08 1984-06-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-06-08 1987-12-08 1988-06-08 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag