초록 ▼

Methanol steam reforming catalysts, and steam reformers and fuel cell systems incorporating the same. In some embodiments, the methanol steam reforming catalyst includes zinc oxide as an active component. In some embodiments, the methanol steam reforming catalyst further includes at least one of chr

Methanol steam reforming catalysts, and steam reformers and fuel cell systems incorporating the same. In some embodiments, the methanol steam reforming catalyst includes zinc oxide as an active component. In some embodiments, the methanol steam reforming catalyst further includes at least one of chromium oxide and calcium aluminate. In some embodiments, the methanol steam reforming catalyst is not pyrophoric. Similarly, in some embodiments, steam reformers including a reforming catalyst according to the present disclosure may include an air-permeable or air-accessible reforming catalyst bed. In some embodiments, the methanol steam reforming catalyst is not reduced during use. In some embodiments, the methanol reforming catalysts are not active at temperatures below 275° C. In some embodiments, the methanol steam reforming catalyst includes a sulfur-absorbent material. Steam reformers, reforming systems, fuel cell systems and methods of using the reforming catalysts are also disclosed.

대표청구항 ▼

I claim: 1. A fuel processing system, comprising: a feedstock delivery system configured to provide a feed stream comprising methanol and water, wherein the feed stream has a methanol to water molar ratio of approximately 1:1; a steam reforming region containing at least one steam reforming catalys

I claim: 1. A fuel processing system, comprising: a feedstock delivery system configured to provide a feed stream comprising methanol and water, wherein the feed stream has a methanol to water molar ratio of approximately 1:1; a steam reforming region containing at least one steam reforming catalyst bed and adapted to receive the feed stream comprising water and methanol; means for heating the reforming region to a temperature in the range of approximately 350-425° C. and vaporizing the feed stream; a catalyst within the at least one reforming catalyst bed and adapted to catalyze the formation of a mixed gas stream comprising hydrogen gas and other gases by steam reforming of the feed stream at a temperature in the range of approximately 350-425° C., wherein hydrogen gas is a majority component of the mixed gas stream, wherein the catalyst contains a mixture that includes 40-60 wt % zinc oxide, 40-60 wt % chromium oxide, and copper oxide, and further wherein the catalyst contains less than approximately 5 wt % copper oxide; and a separation region adapted to receive the mixed gas stream and to separate the mixed gas stream into a product hydrogen stream and a byproduct stream, wherein the product hydrogen stream has at least one of a greater concentration of hydrogen gas than the mixed gas stream and a reduced concentration of at least one component of the other gases than the mixed gas stream, wherein the byproduct stream contains at least one of a lower concentration of hydrogen gas than the mixed gas stream and a greater concentration of at least one component of the other gases than the mixed gas stream. 2. The system of claim 1, wherein the catalyst is non-pyrophoric. 3. The system of claim 2, wherein the catalyst has an initial activity and a second activity after a period of use, the second activity being at least 75% of the initial activity after at least 1000 hours of use. 4. The system of claim 3, wherein the second activity is at least 75% of the initial activity after 5000 hours of use. 5. The system of claim 1, wherein the catalyst contains less than 3 wt % copper oxide. 6. The system of claim 1, wherein the catalyst does not contain palladium or platinum. 7. The system of claim 1, wherein the catalyst does not produce methane during the production of the mixed gas stream. 8. The system of claim 1, wherein the catalyst is adapted to not be sintered during production of the mixed gas stream. 9. The system of claim 1, wherein the reforming catalyst bed is an air-permeable catalyst bed that does not require shielding or isolation from air to prevent air from contacting the catalyst. 10. The system of claim 1, wherein the separation region includes at least one hydrogen-selective membrane having a first surface that is exposed to the mixed gas stream, wherein the product hydrogen stream is formed from at least a portion of the mixed gas stream that permeates though the at least one hydrogen-selective membrane, and further wherein the byproduct stream is formed from at least a portion of the mixed gas stream that does not pass through the at least one hydrogen-selective membrane. 11. The system of claim 10, wherein the at least one hydrogen selective membrane is formed from an alloy comprising palladium and copper. 12. The system of claim 1, wherein the separation region includes at least one pressure swing adsorption system adapted to receive under pressure the mixed gas stream. 13. The system of claim 1, in combination with a fuel cell stack adapted to receive an oxidant stream and at least a portion of the product hydrogen stream and to produce an electric current therefrom. 14. The system of claim 1, wherein the catalyst is adapted to convert at least 75% of the vaporized feed stream into hydrogen gas. 15. The system of claim 1, wherein the catalyst is adapted to convert at least 90% of the vaporized feed stream into hydrogen gas. 16. The system of claim 1, wherein the catalyst further contains at least 3 wt % calcium aluminate. 17. A method of producing hydrogen gas, comprising: providing with a feedstock delivery system a feed stream comprising methanol and water; wherein the feed stream has a methanol to water molar ratio of approximately 1:1; heating a steam reforming region of a fuel processing system with a heated exhaust stream from a heating assembly, wherein the heated exhaust stream has a different composition than the feed stream, and further wherein the steam reforming region includes a catalyst adapted to catalyze the formation of a mixed gas stream comprising hydrogen gas and other gases by steam reforming of the feed stream, wherein the catalyst contains a mixture that includes 40-60 wt % zinc oxide, 40-60 wt % chromium oxide, and copper oxide, and further wherein the catalyst contains less than approximately 5 wt % copper oxide; vaporizing the feed stream; delivering the feed stream to the heated steam reforming region; steam reforming the feed stream in the steam reforming region at a temperature of approximately 350-425° C. to produce a mixed gas stream containing hydrogen gas as a majority component and other eases; and separating the mixed gas stream into a product hydrogen stream and a byproduct stream, wherein the product hydrogen stream has at least one of a greater concentration of hydrogen gas than the mixed gas stream and a reduced concentration of at least one component of the other gases than the mixed gas stream, wherein the byproduct stream contains at least one of a lower concentration of hydrogen gas than the mixed gas stream and a greater concentration of at least one component of the other gases than the mixed gas stream. 18. The method of claim 17, wherein the method further comprises delivering at least a portion of the mixed gas stream to a fuel cell stack adapted to produce an electrical output therefrom. 19. The method of claim 17, wherein the steam reforming does not include producing methane. 20. The method of claim 17, wherein the catalyst is non-pyrophoric. 21. The system of claim 1, wherein the means for heating includes a combustion region that combusts a fuel stream to produce a heated exhaust stream, and further wherein the combustion region is configured to deliver the heated exhaust stream for heat exchange with the steam reforming region to heat the steam reforming region. 22. The system of claim 1, wherein the means for heating includes an electric resistance heater.