Mercury removal sorbent
View Patent ↗A sorbent composition comprising a vanadium compound and a TiO 2 support material is disclosed. Methods of making and using the composition to remove heavy metals or heavy metal containing compounds from a fluid stream are also provided. Such methods are particularly useful in the removal of mercury and mercury compounds from flue gas streams produced from the combustion of hydrocarbon-containing materials such as coal and petroleum fuels.
1. A method for forming a sorbent material comprising:
(a) incorporating into, onto, or into and onto a porous TiO 2 support a mixture including a source of vanadate ions, a solvent capable of solubilizing said source of vanadate ions, and an oxidizing agent;
(b) drying said vanadate incorporated TiO 2 material; and
(c) calcining said dried vanadium incorporated TiO 2 material.
2. A method in accordance with claim 1 wherein said source of vanadate ions comprises NH 4 VO 3 .
3. A method in accordance with claim 1 wherein step (a) includes impregnating said TiO 2 support with said source of vanadate ions.
4. A method in accordance with claim 1 wherein step (a) includes dissolving said source of vanadate ions in said solvent followed by the addition of said oxidizing agent so as to maintain the vanadium present in said vanadate ions in a +5 oxidation state.
5. A method in accordance with claim 1 wherein said solvent is selected from the group consisting of oxalic acid, HNO 3 , HCl, and mixtures thereof.
6. A method in accordance with claim 1 wherein said oxidizing agent is different from said solvent and selected from the group consisting of H 2 SO 4 , HNO 3 , permanganate, ozone, H 2 O 2 , and mixtures thereof.
7. A method in accordance with claim 1 wherein step (c) includes heating said dried vanadium incorporated TiO 2 material to a temperature of between about 482-1472° F.
8. A method in accordance with claim 7 wherein step (c) includes heating said dried vanadium incorporated TiO 2 material to a temperature of between about 572-1112° F.
9. A method in accordance with claim 1 wherein said vanadium oxide compound comprises V 2 O 5 , a hydrate of V 2 O 5 , a peroxo complex of vanadium oxide, or mixtures thereof.
10. A method in accordance with claim 1 wherein said calcined vanadium incorporated TiO 2 material comprises from about 0.5-40% by weight vanadium on an elemental basis.
11. A method in accordance with claim 1 wherein said oxidizing agent is present in the vanadate ion containing mixture of step (a) at a level of about 0.01-25% by weight.
12. A method for forming a sorbent material comprising:
(a) preparing a mixture comprising a source of vanadate ions and a solvent capable of solubilizing said source of vanadate ions;
(b) adding a quantity of an oxidizing agent to said mixture;
(c) intimately mixing said mixture with a quantity of TiO 2 particles;
(d) drying said intimate mixture thereby forming a vanadium incorporated TiO 2 material; and
(c) calcining said vanadium incorporated TiO 2 material.
13. A method in accordance with claim 12 wherein said solvent is selected from the group consisting of oxalic acid, HNO 3 , HCl, and mixtures thereof.
14. A method in accordance with claim 12 wherein said oxidizing agent is different from said solvent and selected from the group consisting of H 2 SO 4 , HNO 3 , permanganate, ozone, H 2 O 2 , and mixtures thereof.
15. A method in accordance with claim 12 wherein said source of vanadate ions comprises NH 4 VO 3 .
16. A method in accordance with claim 12 wherein said oxidizing agent is added to said mixture in step (b) so as to provide from about 0.01-25% of the total weight of the mixture.
17. A method in accordance with claim 12 wherein step (c) includes impregnating said TiO 2 particles with said vanadate ions.
18. A method in accordance with claim 12 wherein step (d) includes heating said mixture to a temperature of at least about 212° F.
19. A method in accordance with claim 12 wherein step (b) includes the drop wise addition of said oxidizing agent to said mixture.
20. A method in accordance with claim 12 wherein said oxidizing agent is added in a sufficient quantity so as to maintain the vanadium present in said vanadate ions in a +5 oxidation state.
21. A method in accordance with claim 12 wherein step (e) includes heating said vanadium incorporated TiO 2 material to a temperature of between about 482-1472° F.
22. A method in accordance with claim 21 wherein step (e) includes heating said vanadium incorporated TiO 2 material to a temperature of between about 572-1112° F.
23. A method in accordance with claim 12 wherein said vanadium oxide compound comprises V 2 O 5 , a hydrate of V 2 O 5 , a peroxo complex of vanadium oxide, or mixtures thereof.
24. A method in accordance with claim 12 wherein said vanadium incorporated TiO 2 material comprises from about 0.5-40% by weight vanadium on an elemental basis.