Ammonia manufacturing apparatus and ammonia manufacturing method

Patent metadata

Field	Value
Publication number	US-2021395902-A1
Application number	US-202117466618-A
Country	US
Kind code	A1
Filing date	Sep 3, 2021
Priority date	Dec 17, 2019
Publication date	Dec 23, 2021
Grant date	—

Abstract

An ammonia manufacturing apparatus includes: an electrochemical reaction unit including a first electrolytic bath for accommodating a first electrolytic solution, an oxidation electrode disposed in the first electrolytic bath, a second electrolytic bath for accommodating a second electrolytic solution containing nitrogen, an ammonia producing catalyst, and a reducing agent, a reduction electrode disposed in the second electrolytic bath, and a diaphragm, and configured to reduce nitrogen by the ammonia producing catalyst and the reducing agent in the second electrolytic bath to produce ammonia, and reduce the reducing agent oxidized due to the production of ammonia, at the reduction electrode by connecting the oxidation electrode and the reduction electrode to a power supply; a nitrogen supply unit including a nitrogen supply part for dissolving nitrogen in the second electrolytic solution; and an ammonia separation unit including a separation part configured to separate ammonia from the second electrolytic solution.

First claim

What is claimed is:

1 . An ammonia manufacturing apparatus comprising:
an electrochemical reaction unit including a first electrolytic bath for accommodating a first electrolytic solution, an oxidation electrode disposed in the first electrolytic bath, a second electrolytic bath for accommodating a second electrolytic solution containing nitrogen, an ammonia producing catalyst, and a reducing agent, a reduction electrode disposed in the second electrolytic bath, and a diaphragm provided between the first electrolytic bath and the second electrolytic bath, and configured to reduce the nitrogen by the ammonia producing catalyst and the reducing agent in the second electrolytic bath to produce ammonia, and reduce the reducing agent oxidized due to the production of the ammonia, at the reduction electrode by connecting the oxidation electrode and the reduction electrode to a power supply; a nitrogen supply unit including a nitrogen supply part for dissolving nitrogen in the second electrolytic solution and configured to sustain a reduction reaction of the nitrogen in the second electrolytic bath; and an ammonia separation unit including a separation part configured to separate the ammonia from the second electrolytic solution containing the ammonia.

2 . The apparatus according to claim 1 , further comprising
an electrolytic solution circulation unit including a circulation pipe for circulating the second electrolytic solution outside the second electrolytic bath, wherein the nitrogen supply part is configured to supply nitrogen to the second electrolytic solution in the circulation pipe including the second electrolytic bath.

3 . The apparatus according to claim 2 , wherein:
the electrolytic solution circulation unit includes an electrolytic solution regulation tank disposed in the circulation pipe and for storing the second electrolytic solution; and the nitrogen supply part is configured to supply nitrogen to the second electrolytic solution stored in the electrolytic solution regulation tank.

4 . The apparatus according to claim 1 , wherein
the nitrogen supply part has a nitrogen supply pipe disposed in the second electrolytic bath to supply nitrogen to the second electrolytic solution via the reduction electrode in a porous shape.

5 . The apparatus according to claim 1 , wherein
the nitrogen supply unit has an oxygen separator configured to separate oxygen in air and take out nitrogen.

6 . The apparatus according to claim 1 , wherein
the ammonia separation unit includes a pipe configured to take part of the second electrolytic solution out of the second electrolytic bath and send the part of the second electrolytic solution to the separation part, and a pipe configured to send the second electrolytic solution from which the ammonia has been separated in the separation part, to the second electrolytic bath.

7 . The apparatus according to claim 1 , further comprising
an electrolytic solution circulation unit including a circulation pipe for circulating the second electrolytic solution outside the second electrolytic bath, wherein the ammonia separation unit includes a pipe configured to take part of the second electrolytic solution circulating in the circulation pipe and send the part of the second electrolytic solution to the separation part, and a pipe configured to send the second electrolytic solution from which the ammonia has been separated in the separation part, to the circulation pipe.

8 . The apparatus according to claim 1 , wherein
the ammonia separation unit includes, as the separation part, a distillation column configured to distill the second electrolytic solution to separate the ammonia.

9 . The apparatus according to claim 1 , wherein
the reducing agent includes a halide of a lanthanoide metal.

10 . The apparatus according to claim 1 , wherein
the ammonia producing catalyst includes a molybdenum complex.

11 . An ammonia manufacturing method comprising:
supplying a first electrolytic solution into a first electrolytic bath of an electrochemical reaction unit and supplying a second electrolytic solution containing nitrogen, an ammonia producing catalyst, and a reducing agent into a second electrolytic bath of the electrochemical reaction unit, the electrochemical reaction unit comprising the first electrolytic bath, an oxidation electrode disposed in the first electrolytic bath, the second electrolytic bath, a reduction electrode disposed in the second electrolytic bath, and a diaphragm provided between the first electrolytic bath and the second electrolytic bath; reducing the nitrogen by the ammonia producing catalyst and the reducing agent in the second electrolytic bath to produce ammonia, and oxidizing the first electrolytic solution at the oxidation electrode in the first electrolytic bath and reducing the reducing agent oxidized due to the production of the ammonia in the second electrolytic bath at the reduction electrode, by supplying electric power from a power supply to the oxidation electrode and the reduction electrode; dissolving nitrogen in the second electrolytic solution so as to sustain a reduction reaction of the nitrogen in the second electrolytic bath; and separating the ammonia from the second electrolytic solution to produce the ammonia.

12 . The method according to claim 11 , wherein:
the dissolving nitrogen into the second electrolytic solution is performed so as to increase a concentration of the ammonia in the second electrolytic solution; and the separating the ammonia is performed so as to separate the ammonia from the second electrolytic solution increased in the concentration of the ammonia.

13 . The method according to claim 11 , further comprising:
circulating the second electrolytic solution outside the second electrolytic bath; supplying nitrogen to the second electrolytic solution in a circulation path of the second electrolytic solution including the second electrolytic bath; and taking at least part of the second electrolytic solution out of the circulation path and separating the ammonia from the second electrolytic solution, and sending the second electrolytic solution from which the ammonia has been separated into the circulation path.

14 . The method according to claim 13 , wherein
nitrogen is supplied to the second electrolytic solution stored in an electrolytic solution regulation tank provided in the circulation path, and the second electrolytic solution from which the ammonia has been separated is sent to the electrolytic solution regulation tank.

15 . The method according to claim 11 , wherein
the reducing agent includes a halide of a lanthanoide metal.

16 . The method according to claim 11 , wherein
the ammonia producing catalyst includes a molybdenum complex.

Assignees

• Toshiba Kk

Inventors

• Tamura Jun
• Mikoshiba Satoshi
• Kitagawa Ryota
• Sugano Yoshitsune
• Mizuguchi Koji

Classifications

• B01J2531/0244

  Pincer-type complexes, i.e. consisting of a tridentate skeleton bound to a metal, e.g. by one to three metal-carbon sigma-bonds · CPC title

• B01J31/1805

  the ligands containing nitrogen · CPC title

• B01J31/2409

  with more than one complexing phosphine-P atom · CPC title

• B01J31/181

  Cyclic ligands, including e.g. non-condensed polycyclic ligands, comprising at least one complexing nitrogen atom as ring member, e.g. pyridine · CPC title

• B01J31/2404

  Cyclic ligands, including e.g. non-condensed polycyclic ligands, the phosphine-P atom being a ring member or a substituent on the ring · CPC title