Methane Reformer for the Production of Hydrogen and a Hydrocarbon Fuel

Abstract

The present disclosure is directed to systems and methods for reforming methane into hydrogen and a hydrocarbon fuel. In example embodiments, the methane reformer integrates a photocatalytic steam methane reforming (P-SMR) system with a subsequent photocatalytic dry methane reforming (P-DMR) system.

Description

Claims

1. A system for recovering syngas from a methane feedstock, comprising: a first stage comprising a photocatalytic steam methane reformer, the first stage configured to produce at least a carbon dioxide stream and a hydrogen stream from the methane feedstock; anda second stage, adjacent to and downstream from the first stage, comprising a photocatalytic dry methane reformer configured to produce the syngas from a second methane feedstock and the carbon dioxide stream produced in the first stage.

2. The system of claim 1, wherein the first stage comprises: the photocatalytic steam methane reformer configured for contacting the methane feedstock with steam in the presence of a first plasmonic photocatalyst to form a first reaction product stream comprising hydrogen and carbon monoxide; anda water-gas shift reactor configured for contacting the first reaction product stream with water to form a water-gas shift stream comprising hydrogen and carbon dioxide.

3. The system of claim 2, wherein the first stage further comprises: a separation unit configured for separating carbon dioxide from the water-gas shift stream to obtain the carbon dioxide stream and the hydrogen stream.

4. The system of claim 2, wherein the photocatalytic steam methane reformer comprises: a housing;at least one reactor cell disposed within an interior of the housing, the at least one reactor cell comprising an enclosure and the first plasmonic photocatalyst on a first catalyst support disposed within the enclosure, wherein the enclosure is optically transparent and comprises at least one input for the methane feedstock to enter the at least one reactor cell and at least one output for the first reaction product stream to exit the at least one reactor cell; andat least one light source, wherein, upon application of the at least one light source, the reactor cell is configured to form the first reaction product stream from the methane feedstock.

5. The system of claim 2, wherein the first plasmonic photocatalyst comprises a first catalyst coupled to a plasmonic material.

6. The system of claim 5, wherein the first catalyst comprises catalytically active iron, nickel, cobalt, platinum, palladium, rhodium, or ruthenium, and wherein the plasmonic material is aluminum, copper, silver, or gold.

7. The system of claim 1, wherein the first stage comprises an organic Rankine cycle to generate electricity within the system using process waste heat.

8. The system of claim 1, wherein the photocatalytic dry methane reformer comprises: a housing;at least one reactor cell disposed within an interior of the housing, the at least one reactor cell comprising an enclosure and a plasmonic photocatalyst on a catalyst support disposed within the enclosure, wherein the enclosure is optically transparent and comprises one or more inputs for the second methane feedstock and the carbon dioxide stream to enter the at least one cell and at least one output for the syngas to exit the at least one cell; andat least one light source, wherein, upon application of the at least one light source, the reactor cell is configured to form the syngas from the second methane feedstock and the carbon dioxide stream.

9. (canceled)

10. (canceled)

11. The system of claim 1, further comprising a third stage, adjacent to and downstream from the second stage, comprising a synthesis reactor configured to produce methanol or dimethyl ether from the syngas produced in the second stage.

12. The system of claim 11, wherein a hydrogen stream is provided to the synthesis reactor in the third stage so that the ratio of carbon monoxide and hydrogen in the synthesis reactor is about 1:2.

13. The system of claim 12, wherein the hydrogen stream is obtained via the first stage.

14. The system of claim 11, wherein the second stage comprises a shift reactor, adjacent to and downstream from the photocatalytic dry methane reformer, the shift reactor configured to produce the hydrogen stream, wherein the hydrogen stream obtained in the second stage is provided to the synthesis reactor in the third stage so that the ratio of carbon monoxide and hydrogen in the synthesis reactor is about 1:2.

15. The system of claim 11, wherein the second stage comprises a hydrogen separation membrane, adjacent to and downstream from the photocatalytic dry methane reformer,-and- wherein the hydrogen separation membrane is configured to produce the hydrogen stream, and wherein the hydrogen stream obtained in the second stage is provided to the synthesis reactor in the third stage so that the ratio of carbon monoxide and hydrogen in the synthesis reactor is about 1:2.

16. A method for transforming a methane feedstock into syngas, comprising: providing the methane feedstock to a first stage comprising a photocatalytic steam methane reformer to obtain at least a carbon dioxide stream and a hydrogen stream; andproviding the carbon dioxide stream to a second stage comprising a photocatalytic dry methane reformer to produce the syngas.

17. The method of claim 16, wherein, in the first stage, the methane feedstock is provided to the photocatalytic steam methane reformer to form a first reaction product stream comprising hydrogen and carbon monoxide, followed by providing the first reaction product stream and water to a water-gas shift reactor to form a water-gas shift stream comprising hydrogen and carbon dioxide.

18. The method of claim 17, the method further comprising: in the photocatalytic steam methane reformer, distributing the methane feedstock into at least one reactor cell disposed within a photocatalytic steam methane reformer housing, wherein each of the at least one reactor cell comprises an optically transparent enclosure and a first plasmonic photocatalyst on a first catalyst support disposed within the optically transparent enclosure;illuminating, via at least one light source, the first plasmonic photocatalyst on the first catalyst support of each of the at least one reactor cell to cause the at least one reactor cell to transform the methane feedstock into the first reaction product stream comprising hydrogen and carbon monoxide; andaccumulating the first reaction product stream from the at least one reactor cell.

19. The method of claim 17, further comprising providing the water-gas shift stream comprising hydrogen and carbon dioxide to a separation unit to obtain the carbon dioxide stream and the hydrogen stream.

20. The method of claim 18, further comprising: in the photocatalytic dry methane reformer, distributing the carbon dioxide stream and a second methane feedstock into at least one second reactor cell disposed within a photocatalytic dry methane reformer housing, wherein each of the at least one second reactor cell comprises an optically transparent enclosure and a second plasmonic photocatalyst on a second catalyst support disposed within the optically transparent enclosure;illuminating, via at least one light source, the second plasmonic photocatalyst on the second catalyst support of each of the at least one second reactor cell to cause the at least one second reactor cell to transform the carbon dioxide and methane into the syngas; andaccumulating the syngas from the at least one second reactor cell.

21. A method for preparing methanol or dimethyl ether from a methane feedstock, comprising: providing the methane feedstock to a first stage comprising a photocatalytic steam methane reformer to obtain at least a carbon dioxide stream and a hydrogen stream;providing the carbon dioxide stream to a second stage comprising a photocatalytic dry methane reformer to produce the syngas; andproviding the syngas to a third stage comprising a synthesis reactor to obtain methanol or dimethyl ether.

22. The method of claim 21, further comprising providing a hydrogen stream to the synthesis rector in the third stage so that the ratio of carbon monoxide and hydrogen in the reactor is about 1:2.

23. The system of claim 3, wherein the photocatalytic steam methane reformer comprises: a housing;at least one reactor cell disposed within an interior of the housing, the at least one reactor cell comprising an enclosure and the first plasmonic photocatalyst on a first catalyst support disposed within the enclosure, wherein the enclosure is optically transparent and comprises at least one input for the methane feedstock to enter the at least one reactor cell and at least one output for the first reaction product stream to exit the at least one reactor cell; andat least one light source, wherein, upon application of the at least one light source, the reactor cell is configured to form the first reaction product stream from the methane feedstock.

24. The system of claim 23, wherein the photocatalytic dry methane reformer comprises: a second housing; andat least one second reactor cell disposed within an interior of the second housing, the at least one second reactor cell comprising a second enclosure and a second plasmonic photocatalyst on a second catalyst support disposed within the second enclosure, wherein the second enclosure is optically transparent and comprises one or more inputs for the second methane feedstock and the carbon dioxide stream to enter the at least one second reactor cell and at least one output for the syngas to exit the at least one second reactor cell; andat least one second light source, wherein, upon application of the at least one second light source, the second reactor cell is configured to form the syngas from the second methane feedstock and the carbon dioxide stream.