ELECTROCHEMICAL PRODUCTION OF UREA FROM NOx AND CARBON DIOXIDE

• US 20110114503A1
• Filed: 09/03/2010
• Published: 05/19/2011
• Est. Priority Date: 07/29/2010
• Status: Active Grant

• Current Assignee: Avantium Knowledge Centre B.V. (Avantium NV)
• Original Assignee: Liquid Light, Inc. (Avantium NV)
• Inventors: Sivasankar, Narayanappa, Bocarsly, Andrew, Teamey, Kyle, Cole, Emily
• Granted Patent: US 8,524,066 B2
• Time in Patent Office: Days
• US Class Current: 205/436
• CPC Class Codes: C25B 1/00 Electrolytic production of inorganic compounds or non-metals
• CPC Class Codes: C25B 1/55 Photoelectrolysis
• CPC Class Codes: C25B 3/00 Electrolytic production of organic compounds
• CPC Class Codes: C25B 3/25 Reduction
• CPC Class Codes: C25B 9/00 Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features

Abstract

Methods and systems for electrochemical production of urea are disclosed. A method may include, but is not limited to, steps (A) to (B). Step (A) may introduce carbon dioxide and NOx to a solution of an electrolyte and a heterocyclic catalyst in an electrochemical cell. The divided electrochemical cell may include an anode in a first cell compartment and a cathode in a second cell compartment. The cathode may reduce the carbon dioxide and the NOx into a first sub-product and a second sub-product, respectively. Step (B) may combine the first sub-product and the second sub-product to produce urea.

Claims

1. A method for electrochemical production of urea, comprising:

(A) introducing carbon dioxide and NOx to a solution of an electrolyte and a heterocyclic catalyst in an electrochemical cell, wherein (i) said electrochemical cell including an anode in a first cell compartment and a cathode in a second cell compartment and (ii) said cathode reducing said carbon dioxide into a first sub-product and reducing said NOx into a second sub-product; and

(B) combining said first sub-product and said second sub-product to produce urea.

2. The method of claim 1, wherein said NOx includes at least one of nitrite or nitrate.

3. The method of claim 1, wherein said first sub-product is at least one of carbon monoxide or a reduced CO₂ intermediate species, and wherein said second sub-product is at least one of ammonia or an ammonia-related intermediate compound.

4. The method of claim 1, wherein said cathode includes at least one of Al, Au, Ag, C, Cd, Co, Cr, Cu, Cu alloys, Ga, Hg, In, Mo, Nb, Ni, Ni alloys, Ni—

Fe alloys, Sn, Sn alloys, Ti, V, W, Zn, elgiloy, Nichrome, austenitic steel, duplex steel, ferritic steel, martensitic steel, stainless steel, degenerately doped p-Si, degenerately doped p-Si;

As, or degenerately doped p-Si;

B.

5. The method of claim 1, wherein said cathode includes a first cathode material for reducing said carbon dioxide and a second material for reducing said NOx.

6. The method of claim 5, wherein said first cathode material includes at least one of tin, silver, copper, steel, or an alloy including at least one of copper or nickel.

7. The method of claim 5, wherein said second cathode material includes at least one of nickel, platinum, or gold.

8. The method of claim 1, wherein said heterocyclic catalyst includes at least one of adenine, a heterocyclic amine containing sulfur, a heterocyclic amine containing oxygen, an azole, benzimidazole, a bipyridine, furan, an imidazole, an imidazole related species with at least one five-member ring, an indole, methylimidazole, an oxazole, phenanthroline, pterin, pteridine, a pyridine, a pyridine related species with at least one six-member ring, pyrrole, quinoline, or a thiazole.

9. A method for electrochemical production of urea, comprising:

(A) introducing carbon dioxide and NOx to a solution of an electrolyte and a heterocyclic catalyst in an electrochemical cell, wherein (i) said electrochemical cell including an anode in a first cell compartment and a cathode in a second cell compartment and (ii) said cathode reducing said carbon dioxide into a first sub-product and reducing said NOx into a second sub-product; and

(B) combining said first sub-product and said second sub-product to produce urea; and

(C) varying a yield of urea by adjusting at least one of (a) a material of said cathode, (b) a type of said heterocyclic catalyst, (c) an electrical potential of said cathode, and (d) a type of said electrolyte.

10. The method of claim 9, wherein said material of said cathode includes at least one of Al, Au, Ag, C, Cd, Co, Cr, Cu, Cu alloys, Ga, Hg, In, Mo, Nb, Ni, Ni alloys, Ni—

Fe alloys, Sn, Sn alloys, Ti, V, W, Zn, elgiloy, Nichrome, austenitic steel, duplex steel, ferritic steel, martensitic steel, stainless steel, degenerately doped p-Si, degenerately doped p-Si;

As, or degenerately doped p-Si;

B.

11. The method of claim 9, wherein said type of said heterocyclic catalyst includes at least one of adenine, a heterocyclic amine containing sulfur, a heterocyclic amine containing oxygen, an azole, benzimidazole, a bipyridine, furan, an imidazole, an imidazole related species with at least one five-member ring, an indole, methylimidazole, an oxazole, phenanthroline, pterin, pteridine, a pyridine, a pyridine related species with at least one six-member ring, pyrrole, quinoline, or a thiazole.

12. The method of claim 9, wherein said electrical potential of said cathode ranges between approximately −

0.5 volts to approximately −

1.5 volts.

13. The method of claim 9, wherein said type of said electrolyte includes at least one of Na₂SO₄, KCl, NaNO₃, NaCl, NaF, NaClO₄, KClO₄, K₂SiO₃, CaCl₂, a H cation, a Li cation, a Na cation, a K cation, a Rb cation, a Cs cation, a Ca cation, an ammonium cation, an alkylammonium cation, a F anion, a Cl anion, a Br anion, an I anion, an At anion, an alkyl amine, borates, carbonates, nitrites, nitrates, phosphates, polyphosphates, perchlorates, silicates, sulfates, or a tetraalkyl ammonium salt.

14. The method of claim 9, wherein combining said first sub-product and said second sub-product includes combining said first sub-product and said second sub-product in said electrochemical cell to produce urea.

15. The method of claim 9, wherein said cathode includes a first cathode material for reducing said carbon dioxide and a second material for reducing said NOx.

16. The method of claim 15, wherein said first cathode material includes at least one of tin, silver, copper, steel, or an alloy including at least one of copper or nickel.

17. The method of claim 15, wherein said second cathode material includes at least one of nickel, platinum, or gold.

18. A system for electrochemical production of urea, comprising:

an electrochemical cell including;

a first cell compartment;

an anode positioned within the first cell compartment;

a second cell compartment;

a separator interposed between the first cell compartment and the second cell compartment, the first cell compartment and the second cell compartment each containing an electrolyte; and

a cathode and a heterocyclic catalyst positioned within the second cell compartment;

a carbon dioxide source, the carbon dioxide source coupled with the second cell compartment, the carbon dioxide source configured to supply carbon dioxide to the cathode;

a NOx source, the NOx source coupled with the second cell compartment, the NOx source configured to supply NOx to the cathode;

a fluid source, the fluid source coupled with the first cell compartment; and

an energy source operably coupled with the anode and the cathode, the energy source configured to provide power to the anode and the cathode, to reduce carbon dioxide at the cathode to a first sub-product, to reduce NOx at the cathode to a second sub-product, and to oxidize the fluid at the anode, the product mixture configured to combine to form urea.

19. The system of claim 18, wherein the cathode includes a stainless steel 316 material.

20. The system of claim 18, wherein a yield of urea is between approximately 90% and 100% relative to a total of carbon-containing products.