Process to prepare adsorbents from organic fertilizer and their applications for removal of acidic gases from wet air streams

• US 20020100367A1
• Filed: 11/29/2001
• Published: 08/01/2002
• Est. Priority Date: 11/29/2000
• Status: Abandoned Application

• Current Assignee: City College of New York
• Original Assignee: City College of New York
• Inventors: Bahryeyev, Andriy, Bandosz, Teresa J., Locke, David C.
• Application Number:
  US09/997,398
• Publication Number:
  US 20020100367A1
• Time in Patent Office: Days
• US Class Current: 95/129
• CPC Class Codes: B01D 2253/10 Inorganic adsorbents
• CPC Class Codes: B01D 2253/102 Carbon
• CPC Class Codes: B01D 2257/302 Sulfur oxides
• CPC Class Codes: B01D 2257/304 Hydrogen sulfide
• CPC Class Codes: B01D 2257/404 Nitrogen oxides other than dinitrogen oxide
• CPC Class Codes: B01D 2257/408 Cyanides, e.g. hydrogen cyanide (HCH)
• CPC Class Codes: B01D 53/02 by adsorption, e.g. preparative gas chromatography solid sorbent compositions B01J20/00, preparation of inorganic compounds or elements C01
• CPC Class Codes: B01D 53/1456 Removing acid components
• CPC Class Codes: B01D 53/8612 Hydrogen sulfide
• CPC Class Codes: B01J 20/0229 Compounds of Fe
• CPC Class Codes: B01J 20/0237 Compounds of Cu
• CPC Class Codes: B01J 20/0244 Compounds of Zn
• CPC Class Codes: B01J 20/041 Oxides or hydroxides
• CPC Class Codes: B01J 20/08 comprising aluminium oxide or hydroxide; comprising bauxite
• CPC Class Codes: B01J 20/103 comprising silica
• CPC Class Codes: B01J 20/20 comprising free carbon; comprising carbon obtained by carbonising processes
• CPC Class Codes: B01J 20/22 comprising organic material
• CPC Class Codes: B01J 20/24 Naturally occurring macromolecular compounds, e.g. humic acids or their derivatives
• CPC Class Codes: B01J 20/28057 Surface area, e.g. B.E.T specific surface area
• CPC Class Codes: B01J 20/28061 being in the range 100-500 m2/g
• CPC Class Codes: B01J 20/28069 : Pore volume, e.g. total pore volume, mesopore volume, micropore volume
• CPC Class Codes: B01J 20/28071 : being less than 0.5 ml/g
• CPC Class Codes: B01J 20/2808 : being less than 2 nm, i.e. micropores or nanopores
• CPC Class Codes: B01J 20/30 : Processes for preparing, regenerating, or reactivating
• CPC Class Codes: B01J 20/3078 : Thermal treatment, e.g. calcining or pyrolizing
• CPC Class Codes: B01J 2220/42 : Materials comprising a mixture of inorganic materials materials coated or impregnated on a carrier B01J20/32
• CPC Class Codes: B01J 2220/4887 : Residues, wastes, e.g. garbage, municipal or industrial sludges, compost, animal manure; fly-ashes
• CPC Class Codes: Y10T 428/2982 : Particulate matter [e.g., sphere, flake, etc.]

Abstract

The invention is directed to an adsorbent comprising: a) 20-30% porous carbon with incorporated organic nitrogen species; and b) 70-80% inorganic matter. The invention is directed to a method of making an adsorbent which comprises: a) thermally drying dewatered sewage sludge to form granulated organic fertilizer; and b) pyrolyzing said the organic fertilizer at temperatures between 600 and 1000° C. The invention is additionally directed to the process of removing acidic gases from wet air streams comprising putting an adsorbent in contact with the wet air stream and allowing the adsorbent to adsorb the acidic gases.

Claims

1. An adsorbent comprising:

a) 20-30% porous carbon with incorporated organic nitrogen species; and

b) 70-80% inorganic matter.

2. The adsorbent of claim 1, wherein the inorganic matter includes highly dispersed catalytic oxides.

3. The adsorbent of claim 2, wherein the catalytic oxides are one or more of copper oxide, zinc oxide, iron oxide, calcium oxide, silica and alumina.

4. The adsorbent of claim 1, wherein the nitrogen species comprises amine or pyridine groups.

5. The adsorbent of claim 1, wherein the surface area of the adsorbent is 100-500 m²/g.

6. The adsorbent of claim 5, wherein the surface area of the adsorbent is 100-200 m²/g.

7. The adsorbent of claim 1, wherein the adsorbent contains micropores and the volume of the micropores are at least 0.03 cm³/g.

8. The adsorbent of claim 1, wherein the pH of the adsorbent is greater than 10.

9. The adsorbent of claim 1, wherein the pH of the adsorbent is between 7 and 10.

10. The adsorbent of claim 1, wherein the pH of the adsorbent is between 4 and 7.

11. A method of making an adsorbent which comprises:

a) thermally drying dewatered sewage sludge to form granulated organic fertilizer; and

b) pyrolyzing said the organic fertilizer at temperatures between 600 and 1000°

C.

12. The method of claim 11, wherein the heating rate is between 5 and 10°

C./minute and the hold time is between 60 and 90 minutes.

13. The method of claim 11, wherein the temperature of pyrolysis is between 800 and 1000°

C.

14. The method of claim 13, wherein the temperature of pyrolysis is between 900 and 1000°

C.

15. The method of claim 11, wherein the temperature of pyrolysis is between 600 and 900°

C. and the adsorbent is further treated with 15-20% HCl.

16. The method of claim 15, wherein the temperature of pyrolysis is between 800 and 900°

C.

17. An adsorbent formed by the method of claim 11.

19. The process of claim 18, wherein the acidic gases are one or more of hydrogen sulfide, sulfur dioxide, hydrogen cyanide, and nitrogen dioxide.

20. The process of claim 18, wherein the acidic gas is hydrogen sulfide which reacts with inorganic matter to be oxidized to sulfur dioxide or elemental sulfur and salt forms thereof.

21. The process of claim 18, wherein the wet air stream is effluent from a sewage treatment plant, gaseous fuel, or gases from hydrothermal vents.

18. The process of removing acidic gases from wet air streams comprising putting an adsorbent comprising 20-30% porous carbon with incorporated organic nitrogen species and 70-80% inorganic matter in contact with the wet air stream and allowing the adsorbent to adsorb the acidic gases.

22. The process of removing acidic gases from wet air streams comprising forming an adsorbent by thermally drying dewatered sewage sludge to form granulated organic fertilizer and pyrolyzing said organic fertilizer at temperatures between 600-1000°

C., putting said adsorbent in contact with the wet air stream, and allowing the adsorbent to adsorb the acidic gases.

23. The process of claim 22, wherein the acidic gases are one or more of hydrogen sulfide, sulfur dioxide, hydrogen cyanide, and nitrogen dioxide.

24. The process of claim 22, wherein the temperature of pyrolysis is between 800 and 1000°

C.

25. The process of claim 24, wherein the temperature of pyrolysis is between 900 and 1000°

C.

26. The process of claim 22, wherein the temperature of pyrolysis is between 600 and 900°

C. and the adsorbent is further treated with 15-20% HCl.

27. The process of claim 26, wherein the temperature of pyrolysis is between 800 and 900°

C.

28. The process of claim 22, wherein the adsorbent may be regenerated by heating to 300-500°

C. to remove elemental sulfur and sulfur dioxide.