Auto thermal reforming (ATR) catalytic systems
An autothermal reforming catalytic structure for generating hydrogen gas from liquid hydrocarbons, steam and an oxygen source. The autothermal reforming catalytic structure includes a support structure and nanosized mixed metal oxide particles dispersed homogenously throughout the support structure.
1. A method for producing a hydrogen rich permeate stream, the method comprising the steps of:
introducing a feed stream comprising a liquid hydrocarbon, steam, and oxygen to a catalytic membrane reactor assembly at an operating temperature and operating pressure, the catalytic membrane reactor assembly comprising a catalytic structure having a porosity in the range of 65% to 70% and metal particles homogeneously distributed throughout the catalytic structure, the operating temperature and operating pressure being selected such that the feed stream undergoes an autothermal reforming (ATR) reaction and a subsequent water-gas-shift (WGS) reaction, wherein the metal particles are formed by conducting a metal reducing step on the catalytic structure having mixed metal oxide particles, the mixed metal oxide particles formed by thermal decomposition of layered double hydroxides in a sol-gel added to a bimodal alumina support structure of the catalytic membrane reactor assembly; and
producing a permeate stream and a retentate stream using the catalytic membrane reactor assembly, wherein the permeate stream comprises hydrogen, wherein the retentate stream comprises carbon dioxide and unreacted hydrocarbons.
2. The method of claim 1 , comprising removing at least a portion of the permeate stream from the catalytic membrane reactor assembly to thereby shift the reaction equilibrium of the ATR reaction and the WGS reaction toward the retentate, wherein removing at least a portion of the permeate stream allows for lowering the operating temperature of the catalytic membrane reactor assembly and decreasing the amount of steam in the feed stream.
3. The method of claim 1 , wherein the liquid hydrocarbon comprises gasoline.
4. The method of claim 1 , wherein the hydrogen is substantially free of carbon monoxide.
5. The method of claim 1 , wherein the operating temperature of the catalytic membrane reactor assembly is within a range of 500° C. to 550° C.
6. The method of claim 1 , wherein the catalytic membrane reactor assembly comprises a hydrogen permeable membrane.
7. The method of claim 6 , comprising removing at least a portion of the permeate stream through the hydrogen permeable membrane.
8. The method of claim 6 , wherein the hydrogen permeable membrane does not include palladium or palladium alloys.
9. The method of claim 6 , wherein the hydrogen permeable membrane comprises a metal doped silica.
10. The method of claim 1 , wherein the catalytic structure comprises an inner surface layer of the catalytic membrane reactor assembly.
11. The method of claim 1 , wherein the metal particles do not include a precious metal.
12. The method of claim 1 , wherein the metal particles include aluminum, nickel, and magnesium.
13. The method of claim 1 , wherein the catalytic structure for the ATR reaction and the WGS reaction is a single layer.