Steam reforming

Patent metadata

Field	Value
Publication number	US-9604200-B2
Application number	US-201414285032-A
Country	US
Kind code	B2
Filing date	May 22, 2014
Priority date	May 24, 2005
Publication date	Mar 28, 2017
Grant date	Mar 28, 2017

Abstract

A process for the steam reforming of hydrocarbons comprises partially oxidizing a feedgas comprising a hydrocarbon feedstock with an oxygen-containing gas in the presence of steam to form a partially oxidized hydrocarbon gas mixture at a temperature >1200° C. and passing the resultant partially oxidized hydrocarbon gas mixture through a bed of steam reforming catalyst, wherein the bed comprises a first layer and a second layer, each layer comprising a catalytically active metal on an oxidic support wherein the oxidic support for the first layer is a zirconia.

First claim

What is claimed:

1. A process for the steam reforming of hydrocarbons comprising;
(i) partially combusting a feedgas comprising a hydrocarbon feedstock with an oxygen-containing gas in the presence of steam at a steam:carbon ratio between 0.5 and 2, in a combustion zone using a burner apparatus to form a partially combusted hydrocarbon gas mixture and
(ii) feeding a gas consisting of the resultant partially combusted hydrocarbon gas mixture at a temperature in the range of 1200-1500° C. from the combustion zone to a steam reforming process by passing it adiabatically through a bed of steam reforming catalyst, the bed comprising a first layer and a second layer, each layer comprising a catalytically active metal on an oxidic support wherein the catalytically active metal in the first layer is rhodium, the oxidic support for the first layer is a zirconia, the catalytically active metal in the second layer is nickel and the oxidic support for the second layer is a refractory support selected from the group consisting of zirconia, alumina, calcium aluminate, magnesium aluminate, titania, magnesia and a mixture thereof
wherein the bed of steam reforming catalyst is disposed below the burner apparatus.

2. The process of claim 1 , wherein at least one of the first layer and the second layer reforming catalysts are particulate, or comprise one or more monolithic supports.

3. The process of claim 1 , wherein the oxidic support for the second layer is alumina or a calcium- or magnesium-aluminate.

4. The process of claim 1 , wherein the first layer of steam reforming catalyst has a higher geometric surface area than the second layer of steam reforming catalyst.

5. The process of claim 1 further comprising a layer of zirconia balls, pellets or tiles placed on top of the first layer of reforming catalyst.

6. The process of claim 1 , wherein the second layer comprises two or more successive layers of a steam reforming catalyst including a third and a further layer, the third or the further layer having a lower catalytic activity than that preceding it.

7. The process of claim 1 , wherein the thickness of the bed of steam reforming catalyst is in the range 3-5 meters.

8. The process of claim 1 , wherein the first layer comprises between 3 and 25% of the thickness of the bed.

9. The process of claim 1 , wherein the first layer comprises between 5 and 15% of the thickness of the bed.

10. The process of claim 1 , wherein the first layer comprises rhodium on a zirconia and the second layer comprises nickel on an alumina or magnesium- or calcium-aluminate.

11. The process of claim 1 , wherein the thickness of the bed of steam reforming catalyst is in the range 1-10 meters.

12. The process of claim 1 , wherein the first layer comprises between 1 and 50% of the thickness of the bed.

13. The process of claim 1 , wherein steam is present at a steam:carbon ratio between 0.5-1.5.

14. The process of claim 1 , wherein steam is present at a steam:carbon ratio between 0.5-1.

15. The process of claim 1 , wherein the steam reforming catalyst in the first layer comprises 0.01-1.00%, Rh by weight.

16. The process of claim 1 , wherein the steam reforming catalyst in the first layer comprises 0.05 to 0.5%, Rh by weight.

Assignees

• Johnson Matthey Plc

Inventors

• Farnell Peter William
• Fowles Martin

Classifications

• Y02P20/52

  using catalysts, e.g. selective catalysts · CPC title

• B01J23/464 Primary

  Rhodium · CPC title

• B01J21/066

  Zirconium or hafnium; Oxides or hydroxides thereof · CPC title

• C01B2203/0233

  the reforming step being a steam reforming step · CPC title

• C01B2203/1023

  Catalysts in the form of a monolith or honeycomb · CPC title