Method for ammonia decomposition to hydrogen and nitrogen

2:

• The method of claim 1, wherein the Ni-SMR catalyst has a temperature programmed reduction (H2-TPR) of 2.5 to 3.5 millimoles (mmol) of H2 per gram of the Ni-SMR catalyst.

3:

• The method of claim 1, wherein the Ni-SMR catalyst has an activation energy of 80 to 90 kilojoules per mole (kJ/mol).

4:

• The method of claim 1, wherein the H2 is present in the H2-containing feed gas stream at a concentration of 90 to 99.99 vol. % based on a total volume of the H2-containing feed gas stream.

5:

• The method of claim 1, wherein the NH3 is present in the NH3-containing feed gas stream at a concentration of 5 to 20 vol. % based on a total volume of the NH3-containing feed gas stream.

6:

• The method of claim 1, wherein the NH3-containing feed gas stream further comprises an inert gas selected from the group consisting of nitrogen, argon, and helium, and wherein a volume ratio of the NH3 to the inert gas present in the NH3-containing feed gas stream is in a range of 1:4 to 1:20.

7:

• The method of claim 6, wherein the NH3-containing feed gas stream further comprises helium, and wherein the residue gas stream leaving the reactor comprises ammonia, nitrogen, helium, and hydrogen.

8:

• The method of claim 1, wherein the reactor is at least one selected from the group consisting of a fixed-bed reactor, a trickle-bed reactor, a moving bed reactor, a rotating bed reactor, a fluidized bed reactor, and a slurry reactor.

10:

• The method of claim 9, wherein the reactor has an aspect ratio of length (L) to inner diameter (ID) of 10:1 to 50:1.

11:

• The method of claim 1, wherein the passing the H2-containing feed gas stream through the reactor is carried out at a weight hourly space velocity of about 9000 mL/gcat/hr at a temperature of about 700° C.

12:

• The method of claim 1, wherein the passing the NH3-containing feed gas stream through the reactor is carried out at a weight hourly space velocity of 4500 to 8100 mL/gcat/hr at a temperature of about 500 to 600° C.

13:

• The method of claim 12, having an ammonia conversion of 60 to 99% based on an initial concentration of the NH3 in the feed gas stream.

15:

• The method of claim 14, wherein the industrial waste material comprises about 40 to 60 wt. % Fe2O3, about 10 to 30 wt. % Al2O3, about 10 to 30 wt. % SiO2, less than 10 wt. % CaO, and less than 10 wt. % Na2O, each wt. % based on a total weight of the industrial waste material.

16:

• The method of claim 15, wherein the industrial waste material comprises about 50 wt. % Fe2O3, about 20 wt. % Al2O3, about 20 wt. % SiO2, less than 10 wt. % CaO, and less than 10 wt. % Na2O, each wt. % based on the total weight of the industrial waste material.

17:

• The method of claim 14, wherein the treated material has a specific surface area in a range of 15 to 25 square meter per gram (m2/g).

18:

• The method of claim 14, wherein the treated material has a cumulative pore volume in a range of 0.05 to 0.06 cubic centimeter per gram (cm3/g).

19:

• The method of claim 14, wherein the Ni salt comprises nickel sulfate, nickel acetate, nickel citrate, nickel iodide, nickel chloride, nickel perchlorate, nickel nitrate, nickel phosphate, nickel triflate, nickel bis(trifluoromethanesulfonyl)imide, nickel tetrafluoroborate, nickel bromide, and/or its hydrate.

20:

• The method of claim 14, wherein the alkali solution comprises at least one alkali salt selected from the group consisting of potassium hydroxide (KOH), sodium hydroxide (NaOH), calcium hydroxide (Ca(OH)2), potassium carbonate (K2CO3), sodium carbonate (Na2CO3), and calcium carbonate (Ca2CO3).