Auto ignition type autothermal reformer and fuel cell system having the same
An auto ignition type autothermal reformer (ATR) performs reproducible ignition using a catalyst that performs ignition without a separate ignition unit, such as an igniter or heating wire, and a fuel cell system having the ATR. The ATR includes a reaction container having a first opening through which a fuel is introduced into the reaction container and a second opening through which a reformate is discharged from the reaction container, the fuel having a mixture of an aqueous primary fuel solution and hydrogen peroxide; a first catalyst disposed adjacent to the first opening in the reaction container, the first catalyst being a granular catalyst; a second catalyst disposed at the rear portion of the first catalyst to promote an autothermal reforming reaction; and a third catalyst disposed at the rear portion of the second catalyst to promote an oxidation reaction.
1. An autothermal reformer (ATR), comprising:
a reaction container having a first opening through which a fuel is introduced into the reaction container and a second opening through which a reformate is discharged from the reaction container, the fuel having a mixture of an aqueous primary fuel solution and hydrogen peroxide;
a first catalyst disposed adjacent to the first opening in the reaction container, the first catalyst being a granular catalyst;
a second catalyst disposed at a rear portion of the first catalyst and configured to promote an autothermal reforming reaction, the second catalyst formed of a monolithic support coated with a catalyst material; and
a third catalyst disposed at a rear portion of the second catalyst and configured to promote an oxidation reaction.
2. The ATR of claim 1 , wherein the first catalyst has any shape of a bead, a pellet, an egg shell, and combinations thereof.
3. The ATR of claim 1 , wherein the size of each of the granules of the granular catalyst is in the range of 0.1 to 10 mm.
4. The ATR of claim 1 , wherein the first catalyst is an ATR catalyst to promote the autothermal reforming reaction.
5. The ATR of claim 1 , wherein the first catalyst is an oxidation catalyst to promote the oxidation reaction.
6. The ATR of claim 5 , wherein the volume of the first catalyst is ¼ to ½ of the volume of the second catalyst.
7. The ATR of claim 1 , wherein the first catalyst includes anyone selected from the group consisting of platinum, palladium, and combinations thereof.
8. The ATR of claim 1 , wherein the first catalyst is an alumina support catalyst comprising platinum and palladium.
9. The ATR of claim 8 , wherein the first catalyst contains 0.1 to 10 wt % of each of the platinum and palladium.
10. The ATR of claim 9 , wherein the first catalyst comprises a promoter selected from the group consisting of cerium (Ce), magnesium (Mg), manganese (Mn), iron (Fe), cobalt (Co), and combinations thereof.
11. The ATR of claim 10 , wherein the content of the promoter in the first catalyst is between about 0.001 to about 5.0 wt %.
12. The ATR of claim 1 , wherein the third catalyst is formed by coating a monolithic support with a catalyst material.
13. The ATR of claim 1 , wherein the third catalyst is a granular catalyst.
14. The ATR of claim 1 , wherein the volume of the third catalyst is ½ to 3/2 of the volume of the second catalyst.
15. The ATR of claim 1 , wherein the fuel has a composition ratio selected in the range of ethanol:water:hydrogen peroxide from about 35:32.5:32.5 to about 25:37.5:37.5.
16. The ATR of claim 15 , wherein the fuel has a composition ratio of ethanol:water:hydrogen peroxide is about 30:35:35.
17. The ATR of claim 1 , wherein the volume of the fuel supplied is in the range of about 1/100 to about 1/10000 of the volume of the reformate produced.
18. The ATR of claim 1 , wherein the fuel is a liquid fuel supplied to the first catalyst.
19. The ATR of claim 1 , wherein the primary fuel includes anyone selected from the group consisting of methanol, ethanol, formic acid, isopropanol, and combinations thereof.
20. The ATR of claim 1 , further comprising a fourth catalyst disposed at a rear portion of the third catalyst to reduce the concentration of carbon monoxide contained in the reformate produced in the second catalyst.
21. The ATR of claim 20 , wherein the fourth catalyst is a transfer catalyst to convert the carbon monoxide and water into hydrogen and carbon dioxide.
22. An auto ignition autothermal reformer (ATR), comprising:
a first granular oxidation catalyst;
an autothermal reforming catalyst disposed after the first granular oxidation catalyst with respect to a flow direction of a fuel in the ATR, the autothermal reforming catalyst comprising a monolithic catalyst; and
a second oxidation catalyst disposed after the autothermal reforming catalyst with respect to the flow direction of the fuel in the ATR.
23. The ATR of claim 22 , wherein the second oxidation catalyst is a monolithic catalyst.
24. The ATR of claim 22 , further comprising:
a transfer catalyst disposed after the second oxidation catalyst with respect to the flow direction of the fuel in the ATR.
25. The ATR of claim 24 , wherein the second oxidation catalyst is a granular catalyst.
26. The ATR of claim 22 , wherein the fuel comprises:
a primary fuel; water; and
hydrogen peroxide.
27. The ATR of claim 26 , wherein the primary fuel is one of methanol, ethanol, formic acid, isopropanol, and combinations thereof.
28. The ATR of claim 26 , wherein the fuel has a primary fuel:water:hydrogen peroxide composition of about 35:32.5:32.5 to about 25:37.5:37.5.
29. The ATR of claim 22 , wherein the ATR does not include an ignition unit.