Claims
- 1. A method of making a catalyst for use in the dehydrogenation of ethylbenzene to styrene, said catalyst comprising from about 20 wt % to about 90 wt % iron oxide calculated as Fe2O3, from about 5 wt % to about 20 wt % of an alkali metal compound calculated as an alkali metal oxide, from about 0.1 ppm to about 1,000 ppm of a source of palladium or platinum selected from the group including elemental palladium, elemental platinum, compounds containing palladium, compounds containing platinum and combinations thereof, from about 0.5 wt % to about 10.0 wt % of a molybdenum or tungsten compound calculated as MoO3 or WO3, and from about 4.0 wt % to about 20 wt % of a cerium compound, calculated as CeO2, wherein all weight percents are based on the total weight of the catalyst, and said method comprising:
a) preparing an aqueous organic acid solution, wherein said organic acid is a carboxylic acid having at least one carboxylic acid group with a pKa at ambient temperature of from about 0.5 to about 6; b) adding iron metal to said acid solution; c) forcing an oxidative agent through said acid solution until said iron metal is consumed and an iron slurry is formed; d) spray drying said iron slurry with a wheel atomizer to form iron oxide having a surface area of from about 2 m2/g to about 40 m2/g; e) calcining said iron oxide at a temperature of about 1200° F. until the calcined iron oxide has a surface area of from about 2 m2/g to about 80 m2/g; f) mixing the iron oxide with a promoter; g) forming a catalyst pellet by pressure forming; and h) calcining said particles to form said catalyst.
- 2. The method of claim 1 wherein said organic acid is selected from the group consisting of formic acid, acetic acid, glycolic acid, oxalic acid, pyruvic acid, malonic acid, citric acid and propionic acid, and a combination thereof.
- 3. The method of claim 1 wherein said iron metal is a powder, granule, sphere, chip or other form having an average diameter of from about 1μ to about 500μ.
- 4. The method of claim 1 wherein said promoter is selected from the group consisting of cerium, titanium, molybdenum, tungsten, chromium, aluminum, silicon, zinc, manganese, cobalt, cadmium, vanadium and copper, and combinations thereof.
- 5. The method of claim 1 wherein said oxidizing agent is air, compressed air, oxygen, hydrogen peroxide, an organic peroxide, ozone and a combination thereof.
- 6. The method of claim 1 wherein said catalyst comprises from about 20 wt % to about 90 wt % iron oxide calculated as Fe2O3, about 5 wt % to about 20 wt % of an alkali metal compound, about 4.0 wt % to about 20 wt % of cerium oxide calculated as CeO2, about 0.5 wt % to about 10.0 wt % of molybdenum or tungsten oxide calculated as MoO3 or WO3, about 0.2 wt % to about 10.0 wt % of calcium or magnesium oxide, about 10 ppm to about 1000 ppm of titanium oxide calculated as TiO2, about 100 ppm to about 2000 ppm of chromium oxide calculated as Cr2O3, and about 1 ppm to about 1000 ppm of a source for palladium or platinum, calculated on an elemental basis.
- 7. The method of claim 6 wherein said alkali metal compound is potassium oxide.
- 8. The method of claim 6 wherein said catalyst further comprises from about 0.05 wt % to about 10.0 wt % of an oxide of aluminum, silicon, manganese, copper, zinc, cadmium, vanadium, and cobalt, calculated on an elemental basis.
- 9. A method of making a catalyst for use in the dehydrogenation of ethylbenzene to styrene, said catalyst comprising a high purity iron and at least one promoter, and said method comprising:
a) preparing an aqueous organic acid solution, wherein said organic acid is a carboxylic acid having at least one carboxylic acid group with a pKa at ambient temperature of from about 0.5 to about 6; b) adding high purity iron metal to said acid solution, wherein said iron metal is a powder, granule, sphere, chip or other form having an average diameter of from about 1μ to about 500μ; c) forcing an oxidative agent selected from the group consisting of air, compressed air, oxygen, hydrogen peroxide, an organic peroxide, ozone and a combination thereof, through said acid solution until said iron metal is consumed and an iron slurry is formed; d) spray drying said iron slurry with a wheel atomizer to form iron oxide having a surface area of from about 2 m2/g to about 40 m2/g; e) calcining said iron oxide at a temperature of about 1200° F. until the calcined iron oxide has a surface area of from about 2 m2/g to about 80 m2/g; f) mixing the iron oxide with a promoter; g) forming a catalyst pellet by pressure forming; and h) calcining said particles to form said catalyst.
- 10. The method of claim 9 wherein said organic acid is selected from the group consisting of formic acid, acetic acid, glycolic acid, oxalic acid, pyruvic acid, malonic acid, citric acid and propionic acid, and a combination thereof.
- 11. The method of claim 9 wherein said promoter is selected from the group consisting of cerium, titanium, molybdenum, tungsten, chromium, aluminum, silicon, zinc, manganese, cobalt, cadmium, vanadium and copper, and combinations thereof.
- 12. The method of claim 9 wherein said catalyst comprises from about 20 wt % to about 90 wt % iron oxide calculated as Fe2O3, from about 5 wt % to about 20 wt % of an alkali metal compound calculated as an alkali metal oxide, from about 0.1 ppm to about 1,000 ppm of a source of palladium or platinum selected from the group including elemental palladium, elemental platinum, compounds containing palladium, compounds containing platinum and combinations thereof, from about 0.5 wt % to about 10.0 wt % of a molybdenum or tungsten compound calculated as MoO3 or WO3, and from about 4.0 wt % to about 20 wt % of a cerium compound, calculated as CeO2, wherein all weight percents are based on the total weight of the catalyst,
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation-in-part application to PCT Patent Application Serial Number PCT/US02/15310 filed May 15, 2002, currently pending, and incorporated herein in its entirety by reference.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
PCT/US02/15310 |
May 2002 |
US |
Child |
10876150 |
Jun 2004 |
US |