Solid ammonia storage and delivery material

• US 9,889,403 B2
• Filed: 02/26/2013
• Issued: 02/13/2018
• Est. Priority Date: 08/03/2004
• Status: Expired due to Fees

• Current Assignee: Amminex Emissions Technology A/S (Faurecia SA)
• Original Assignee: Amminex Emissions Technology A/S (Faurecia SA)
• Inventors: Christensen, Claus Hviid, Johannessen, Tue, Quaade, Ulrich, Nrskov, Jens Kehlet, Srensen, Rasmus Zink
• Primary Examiner(s): Olsen, Kaj K
• Application Number:
  US13/777,175
• Publication Number:
  US 20130230443A1
• Time in Patent Office: 1,813 Days
• Field of Search: 423351, 423352, 423383, 423395, 423497
• CPC Class Codes: B01D 53/565 by treating the gases with solids
• CPC Class Codes: B01D 53/90 Injecting reactants
• CPC Class Codes: B01D 53/9431 Processes characterised by a specific device
• CPC Class Codes: B01J 20/046 containing halogens, e.g. halides
• CPC Class Codes: B01J 20/28011 Other properties, e.g. density, crush strength
• CPC Class Codes: B01J 20/3035 Compressing
• CPC Class Codes: C01C 1/006 making use of solid ammonia storage materials, e.g. complex ammine salts
• CPC Class Codes: C01F 5/00 Compounds of magnesium
• CPC Class Codes: C01G 3/14 Complexes with ammonia
• CPC Class Codes: C01G 45/00 Compounds of manganese
• CPC Class Codes: C01G 49/00 Compounds of iron
• CPC Class Codes: C01G 51/12 Complexes with ammonia
• CPC Class Codes: C01G 53/12 Complexes with ammonia
• CPC Class Codes: C01G 9/00 Compounds of zinc
• CPC Class Codes: C01P 2006/10 Solid density
• CPC Class Codes: F01N 2610/02 the substance being ammonia or urea
• CPC Class Codes: F01N 2610/06 the substance being in the gaseous form
• CPC Class Codes: F01N 2610/10 the substance being heated, e.g. by heating tank or supply line of the added substance
• CPC Class Codes: F01N 3/2066 Selective catalytic reduction [SCR]
• CPC Class Codes: F17C 11/00 Use of gas-solvents or gas-sorbents in vessels absorbing compositions for acetylene C10L3/04; absorbing compositions for hydrogen C01B3/0005
• CPC Class Codes: Y02T 10/12 : Improving ICE efficiencies

Abstract

Disclosed is a method for the selective catalytic reduction of NO_x in waste/exhaust gas by using ammonia provides by heating one or more salts of formula M_a(NH₃)_nX_z, wherein M represents one or more cations selected from alkaline earth metals and transition metals, X represents one or more anions, a represents the number of cations per salt molecule, z represents the number of anions per salt molecule, and n is a number of from 2 to 12, the one or more salts having been compressed to a bulk density above 70% of the skeleton density before use thereof.

Claims

1. A method for the selective catalytic reduction of NO_x in waste gas containing oxygen by using ammonia and a reduction catalyst, wherein the method comprises providing gaseous ammonia by heating a solid storage medium capable of releasing ammonia and comprising one or more salts of general formula:

M_a(NH₃)_nX_z,

wherein M represents one or more cations selected from alkaline earth metals and transition metals, X represents one or more anions, a represents the number of cations per salt molecule, z represents the number of anions per salt molecule, and n is a number of from 2 to 12, the one or more salts having been compressed to a bulk density above 70% of a skeleton density before use thereof, and controlling a release rate of ammonia depending on a content of NO_x in the waste gas.

2. The method of claim 1, wherein M comprises at least one metal selected from Mn, Fe, Co, Ni, Cu, and Zn.

3. The method of claim 1, wherein X comprises at least one of sulfate and chloride.

4. The method of claim 1, wherein M comprises Mg.

5. The method of claim 1, wherein before use the one or more salts have been compressed to a bulk density above 80% of the skeleton density.

6. The method of claim 1, wherein before use the one or more salts have been compressed to a bulk density above 85% of the skeleton density.

7. A method for the selective catalytic reduction of NO_x in an exhaust gas from a combustion process, wherein the method comprises contacting the exhaust gas with ammonia as reducing agent, the ammonia being provided by desorption of ammonia from one or more salts of general formula:

M_a(NH₃)_nX_z,

wherein M represents one or more cations selected from alkaline earth metals and transition metals, X represents one or more anions, a represents the number of cations per salt molecule, z represents the number of anions per salt molecule, and n is a number of from 2 to 12, the one or more salts having been compressed to a bulk density above 70% of a skeleton density before use thereof.

8. The method of claim 7, wherein M comprises at least one metal selected from Mn, Fe, Co, Ni, Cu, and Zn.

9. The method of claim 7, wherein X comprises at least one of sulfate and chloride.

10. The method of claim 7, wherein M comprises Mg.

11. The method of claim 7, wherein the one or more salts comprise Mg(NH₃)₆Cl₂.

12. The method of claim 7, wherein before use the one or more salts have been compressed to a bulk density above 80% of the skeleton density.

13. The method of claim 7, wherein before use the one or more salts have been compressed to a bulk density above 85% of the skeleton density.

14. A method for the selective catalytic reduction of NO_x in an exhaust gas from a combustion process, wherein the method comprises contacting the exhaust gas with ammonia delivered from an ammonia delivery device that comprises a container having therein one or more salts of general formula:

M_a(NH₃)_nX_z,

wherein M represents one or more cations selected from alkaline earth metals and transition metals, X represents one or more anions, a represents the number of cations per salt molecule, z represents the number of anions per salt molecule, and n is a number of from 2 to 12, the one or more salts having been compressed to a bulk density above 70% of a skeleton density before use thereof, and wherein the container comprises one or more closable outlet openings connected to a pipe and further is provided with an element for heating the container and the one or more salts contained therein.

15. The method of claim 14, wherein M comprises at least one metal selected from Mn, Fe, Co, Ni, Cu, and Zn.

16. The method of claim 14, wherein X comprises at least one of sulfate and chloride.

17. The method of claim 14, wherein M comprises Mg.

18. The method of claim 14, wherein the one or more salts comprise Mg(NH₃)₆Cl₂.

19. The method of claim 14, wherein before use the one or more salts have been compressed to a bulk density above 80% of the skeleton density.

20. The method of claim 14, wherein before use the one or more salts have been compressed to a bulk density above 85% of the skeleton density.