CORE-SHELL CATALYST FOR NATURAL GAS REFORMING
A natural gas reforming catalyst includes a metal core and rhodium deposited on the metal core. A natural gas reformer includes a hydrocarbon inlet, a reforming catalyst for generating hydrogen from a hydrocarbon and water and a hydrogen outlet. The reforming catalyst includes a metal core and a rhodium layer deposited on the metal core. A method for preparing a natural gas reforming catalyst includes adding a rhodium compound and a metal core to a reaction vessel and depositing the rhodium compound on the metal core.
1 . A natural gas reforming catalyst comprising:
a metal core; and
rhodium deposited on the metal core.
2 . The natural gas reforming catalyst of claim 1 , wherein the metal core comprises nickel.
3 . The natural gas reforming catalyst of claim 1 , wherein the metal core comprises palladium.
4 . The natural gas reforming catalyst of claim 1 , wherein the rhodium is alloyed with a metal selected from the group consisting of platinum, palladium, iridium and combinations thereof.
5 . The natural gas reforming catalyst of claim 1 , wherein the rhodium is deposited on the metal core as a monolayer.
6 . The natural gas reforming catalyst of claim 5 , wherein the rhodium monolayer has a thickness of about 0.25 nanometers.
7 . The natural gas reforming catalyst of claim 1 , wherein the rhodium is deposited on the metal core as a submonolayer.
8 . The natural gas reforming catalyst of claim 7 , wherein the metal core has a surface, and wherein rhodium covers between about 10% and about 80% of the surface of the metal core.
9 . The natural gas reforming catalyst of claim 8 , wherein rhodium covers between about 10% and about 100% of the surface of the metal core.
10 . The natural gas reforming catalyst of claim 1 , wherein multiple layers of rhodium are deposited on the metal core.
11 . The natural gas reforming catalyst of claim 10 , wherein the multiple layers of rhodium have a combined thickness between about 0.5 nanometers and about 3 nanometers.
12 . A natural gas reformer comprising:
a hydrocarbon inlet;
a reforming catalyst for generating hydrogen from a hydrocarbon and water, the reforming catalyst comprising:
a metal core; and
a rhodium layer deposited on the metal core; and
a hydrogen outlet.
13 . The natural gas reformer of claim 12 , wherein the hydrocarbon inlet receives natural gas.
14 . The natural gas reformer of claim 12 , wherein the hydrogen exiting the hydrogen outlet contains no more than 20 ppm ammonia.
15 . A method for preparing a natural gas reforming catalyst, the method comprising:
adding a rhodium compound and a metal core to a reaction vessel; and
depositing the rhodium compound on the metal core.
16 . The method of claim 15 , wherein the rhodium compound is a rhodium salt.
17 . The method of claim 16 , wherein the rhodium salt is selected from the group consisting of rhodium acetate, rhodium chloride, rhodium nitride and combinations thereof.
18 . The method of claim 15 , wherein the metal core comprises nickel, and wherein the nickel reduces the rhodium salt to form a rhodium layer on a surface of the metal core.
19 . The method of claim 15 , further comprising:
adding an aqueous solvent selected from the group consisting of water, aqueous acids, organic solvents and combinations thereof to the reaction vessel.
20 . The method of claim 15 , further comprising:
adding an inert gas selected from the group consisting of argon, nitrogen and combinations thereof to the reaction vessel.