Carbon sorbents for the removal of nitrogen oxides and methods for making the same
Adsorbents including a sorbent, at least one metal additive and greater than about 5 wt. % triethylenediamine are described herein. Methods for making such adsorbents and filters comprising the adsorbents are also described.
1. A composition for removing NO 2 from a gas stream, comprising:
a first sorbent having a first surface deposition comprising:
about 2 wt. % to about 12 wt. % copper;
about 1 wt. % to about 5 wt. % molybdenum;
about 3 wt. % to about 6 wt. % sulfate;
about 8 wt. % to about 15 wt. % triethylenediamine; and
about 0.03 wt. % to about 1.0 wt. % silver.
2. The composition of claim 1 , wherein the first surface deposition further comprises about 2 wt. % to about 12 wt. % zinc.
3. The composition of claim 1 , wherein the first surface deposition comprises about 8 wt. % to about 10 wt. % triethylenediamine.
4. The composition of claim 1 , wherein the first sorbent further comprises about 2 wt. % to about 20 wt. % water.
5. The composition of claim 1 , wherein the first sorbent is selected from the group consisting of activated carbon, natural and synthetic zeolite, silica, silica gel, alumina, zirconia, and diatomaceous earths.
6. The composition of claim 1 , further comprising:
a second sorbent for removal of ammonia.
7. The composition of claim 6 , wherein the first surface deposition further comprises about 2 wt. % to about 12 wt. % zinc.
8. The composition of claim 6 , wherein the first sorbent and the second sorbent are admixed.
9. The composition of claim 6 , wherein the first sorbent and the second sorbent are layered.
10. The composition of claim 6 , wherein the second sorbent has a second surface deposition comprising at least one of zinc chloride, phosphoric acid, sulfuric acid, citric acid, nickel chloride, and combinations thereof.
11. The composition of claim 6 , wherein the second sorbent is selected from the group consisting of activated carbon, natural and synthetic zeolite, silica, silica gel, alumina, zirconia, and diatomaceous earths.
12. A method of making a composition for removing NO 2 from a gas stream, the method comprising:
impregnating a first sorbent material with a first surface deposition comprising:
about 2 wt. % to about 12 wt. % copper;
about 1 wt. % to about 5 wt. % molybdenum;
about 3 wt. % to about 6 wt. % sulfate;
about 8 wt. % to about 15 wt. % triethylenediamine; and
about 0.03 wt. % to about 1.0 wt. % silver.
13. The method of claim 12 , wherein the first surface deposition further comprises about 2 wt. % to about 12 wt. % zinc.
14. The method of claim 12 , the first surface deposition comprising about 8 wt. % to about 10 wt. % triethylenediamine.
15. The method of claim 12 , further comprising providing a second sorbent for removal of ammonia.
16. The method of claim 15 , wherein the first surface deposition further comprises about 2 wt. % to about 12 wt. % zinc.
17. The method of claim 15 , further comprising impregnating the second sorbent with at least one of zinc chloride, phosphoric acid, sulfuric acid, citric acid, nickel chloride, and combinations thereof.
18. A method of removing NO 2 from a gas stream, the method comprising:
providing a composition comprising:
a first sorbent having a first surface deposition comprising:
about 2 wt. % to about 12 wt. % copper;
about 1 wt. % to about 5 wt. % molybdenum;
about 3 wt. % to about 6 wt. % sulfate;
about 8 wt. % to about 15 wt. % triethylenediamine; and
about 0.03 wt. % to about 1.0 wt. % silver; and
contacting the composition with a gas stream that contains NO 2 .
19. The method of claim 18 , wherein the first surface deposition further comprises about 2 wt. % to about 12 wt. % zinc.
20. The method of claim 18 , wherein the first surface deposition comprises about 8 wt. % to about 10 wt. % triethylenediamine.
21. The method of claim 18 , wherein the composition further comprises a second sorbent for removal of ammonia.
22. The method of claim 21 , wherein the first surface deposition further comprises about 2 wt. % to about 15 wt. % zinc.
23. The method of claim 21 , wherein the second sorbent has a second surface deposition comprising at least one of zinc chloride, phosphoric acid, sulfuric acid, citric acid, nickel chloride, and combinations thereof.
24. The method of claim 18 , wherein composition is provided within a filter, and the filter includes an air filter for civilian or military applications, a personal protection gas mask filter, a first responder mask filter, a collective protection filter, an air filter for industrial applications, or a filter for automotive cabin air purification.