Catalyst and systems incorporating the catalyst

• US 7,972,569 B2
• Filed: 01/28/2009
• Issued: 07/05/2011
• Est. Priority Date: 01/29/2008
• Status: Active Grant

• Current Assignee: UChicago Argonne LLC
• Original Assignee: UChicago Argonne LLC
• Inventors: Zajac, Gerry, Stair, Peter C., Elam, Jeffrey W., Pellin, Michael J., Cohen, Steven A., Libera, Joseph A.
• Primary Examiner(s): Griffin; Walter D
• Assistant Examiner(s): SEIFU, LESSANEWORK T
• Application Number:
  US12/361,377
• Publication Number:
  US 20090191101A1
• Time in Patent Office: 888 Days
• Field of Search: 422/211, 422/222, 422/139, 502/353, 502/305, 502/312, 502/439
• US Class Current: 422/211
• CPC Class Codes: B01J 23/002 Mixed oxides other than spinels, e.g. perovskite
• CPC Class Codes: B01J 23/30 Tungsten
• CPC Class Codes: B01J 2523/00 Constitutive chemical elements of heterogeneous catalysts
• CPC Class Codes: B01J 2523/55 Vanadium
• CPC Class Codes: B01J 2523/56 Niobium
• CPC Class Codes: B01J 2523/69 Tungsten
• CPC Class Codes: B01J 35/40 characterised by dimensions, e.g. grain size in a colloidal state B01J35/23; crystallite size B01J35/77
• CPC Class Codes: B01J 35/59 Membranes
• CPC Class Codes: B01J 35/613 10-100 m2/g
• CPC Class Codes: B01J 35/615 100-500 m2/g
• CPC Class Codes: B01J 35/647 2-50 nm
• CPC Class Codes: B01J 37/0238 via the gaseous phase-sublimation
• CPC Class Codes: B01J 37/0244 Coatings comprising several layers
• CPC Class Codes: B01J 8/1836 Heating and cooling the reactor B01J8/42 takes precedence
• CPC Class Codes: C23C 16/405 of refractory metals or yttrium
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]

Abstract

A catalyst includes a carrier body and a catalytic portion carried by the carrier body. The catalytic portion includes a plurality of distinct layers of catalytic material, which layers may be deposited through atomic layer deposition techniques. The catalyst may have a selectivity for the conversion of alkanes to alkenes of over 50%. The catalyst may be incorporated in a reactor such as a fluidized bed reactor or a single pass reactor.

Claims

1. A catalyst comprising:

a carrier body; and

a catalytic portion carried by the carrier body, the catalytic portion comprising a plurality of distinct layers of a catalytic material, each of the plurality of distinct layers of the catalytic material including a transition metal oxide and having an average thickness of between about 0.01 nm and about 500 nm,

wherein the plurality of distinct layers of catalytic material comprise a plurality of different transition metal oxides, and wherein the catalyst is configured to catalyze at least one of a dehydrogenation reaction and an ammoxidation reaction.

2. The catalyst of claim 1, wherein the carrier body is porous, and wherein the catalytic portion is disposed on a plurality of pore surfaces.

3. The catalyst of claim 2, wherein the pores of the carrier body have a mean pore size that is between about 0.1 nm and about 1 μ

m.

4. The catalyst of claim 3, wherein the carrier body consists essentially of a ceramic material having a surface area of at least about 1 m²/g.

5. The catalyst of claim 1, wherein at least one of the plurality of different transition metal oxides is selected from the group consisting of:

V₂O₅, WO₃, MoO₃, NbO₂, TiO₂, Al₂O₃, MgO, and ZrO₂.

6. The catalyst of claim 5, wherein the plurality of distinct layers include at least three different transition metal oxides.

7. The catalyst of claim 1, wherein at least a first layer of the plurality of layers of catalytic material comprises a vanadium oxide based catalytic material, and wherein at least a second layer of the plurality of layers of catalytic material comprises a niobium oxide based catalytic material.

8. The catalyst of claim 6, wherein at least a third layer of the plurality of layers of catalytic material comprises a tungsten oxide based catalytic material.

9. The catalyst of claim 6, wherein the catalyst is substantially characterized by an oxidative dehydrogenation of propane to propylene with a selectivity to propylene of at least about 50 percent and a conversion rate of at least about 10 percent.

10. The catalyst of claim 1, wherein the average thickness of each of the plurality of distinct layers of catalytic material is between about 1 nm and about 100 nm.

11. The catalyst of claim 1, wherein the catalytic portion substantially conforms to a shape of the carrier body.

12. A method for forming a catalyst comprising:

providing a carrier body;

depositing a catalytic material on the carrier body comprising a plurality of transition metal oxides;

wherein depositing a catalytic material on the carrier body comprises depositing a plurality of layers of the catalytic material, on the carrier body one layer at a time, wherein at least one layer of the plurality of layers comprises a first transition metal oxide and at least another layer comprises a second transition metal oxide, and wherein the catalyst is configured to catalyze at least one of a dehydrogenation reaction and an ammoxidation reaction.

13. The method of claim 12, wherein depositing one layer of the catalytic material comprises providing a metal-based precursor to the carrier body, and oxidizing the metal-based precursor to form the catalytic material.

14. The method of claim 13, wherein providing a metal-based precursor to the carrier body comprises providing the metal-based precursor to a carrier body that comprises at least one layer of catalytic material that has been deposited on the carrier body.

15. The method of claim 13, wherein the first and second transition metal oxides are selected from the group consisting of:

V₂O₅, WO₃, MoO₃, NbO₂, TiO₂, Al₂O₃, MgO, and ZrO₂.

16. The method of claim 12, wherein depositing one layer of the catalytic material comprises wet impregnation.

17. A reactor comprising:

a reactor tank comprising an inlet port configured to receive reactants and an outlet port configured to allow reacted products to leave the reactor tank;

a reactant source configured to provide a source of short chain alkane reactants to the reactor; and

a catalyst disposed within the reactor, the catalyst comprising;

a carrier body; and

a catalytic portion carried by the carrier body, the catalytic portion including a plurality of distinct layers of a catalytic material, each of the plurality of distinct layers of the catalytic material including a transition metal oxide, at least one of the plurality of layers including a first transition metal oxide and at least another of the plurality of layers including a second transition metal oxide,

wherein the catalyst is configured to catalyze a conversion of an alkane reactant to an alkene product, wherein the catalyst has a selectivity of at least about 45 percent for the conversion of the alkane reactant to the alkene product.

18. The reactor of claim 17, wherein the reactor is configured to fluidize the catalyst in the reactor.

19. The reactor of claim 17, wherein the carrier body comprises a plurality porous particles having a mean pore size of at least about 0.1 nm and a surface area of at least about 1 m²/g.

20. The reactor of claim 17, wherein the transition metal oxides are selected from the group consisting of:

V₂O₅, WO₃, MoO₃, NbO₂, TiO₂, Al₂O₃, MgO, and ZrO₂.