Production method of aluminum using hydrate

Patent metadata

Field	Value
Publication number	US-10927469-B2
Application number	US-201916662898-A
Country	US
Kind code	B2
Filing date	Oct 24, 2019
Priority date	Oct 25, 2018
Publication date	Feb 23, 2021
Grant date	Feb 23, 2021

Abstract

A production method of aluminum including: a step of synthesizing an aluminum compound from a mixture including a halogenated aluminum hydrate and a perfluoroalkylsulfonimide-type or perfluoroalkylsulfonamide-type ionic liquid represented by general formula (1); a step of dissolving the aluminum compound in a nitrile-based organic solvent to prepare an aluminum electrolyte; a step of adding at least one ligand selected from a phosphorus compound and an organic compound having an amide group to the aluminum electrolyte and dehydrating water molecules from a hydrate included in the aluminum electrolyte; and a step of electrodepositing aluminum on a cathode by allowing electricity to pass between an anode and the cathode in the aluminum electrolyte after the dehydrating step.

First claim

What is claimed is:

1. A production method of aluminum comprising:
a step of synthesizing an aluminum compound derived from an aluminum perfluoroalkyl sulfonyl imide or an aluminum perfluoroalkyl sulfonyl amide from a mixture including a halogenated aluminum hydrate and a perfluoroalkylsulfonimide-type or perfluoroalkylsulfonamide-type ionic liquid represented by following general formula (1):
wherein
Rf 1 and Rf 2 are each independently CF 3 or C 4 F 9 , and

M is H, alkali metal, quaternary ammonium or imidazolium;
a step of dissolving the aluminum compound in a nitrile-based organic solvent to prepare an aluminum electrolyte;
a step of adding at least one ligand selected from either a phosphorus compound or an organic compound having an amide group to the aluminum electrolyte wherein the at least one ligand dehydrates water molecules from a hydrate included in the aluminum electrolyte; and
a step of electrodepositing aluminum on a cathode by allowing electricity to pass between an anode and the cathode in the aluminum electrolyte after the adding step.

2. The production method of aluminum according to claim 1 , wherein the aluminum electrolyte with the at least one ligand added is stirred at 0° C. or higher and 100° C. or lower in the adding step.

3. The production method of aluminum according to claim 1 , wherein constant potential electrolysis with an electrode potential with respect to aluminum used as a reference electrode of −6.0 V or more and less than 0 V or constant current electrolysis with a current density of 1 μAcm −2 or more and 10000 μAcm −2 or less is carried out in the electrodepositing step.

4. The production method of aluminum according to claim 1 , wherein a temperature of an electrolytic bath is 20° C. or higher and 100° C. or lower in the electrodepositing step.

5. The production method of aluminum according to claim 1 , wherein Rf 1 and Rf 2 in the general formula (1) are CF 3 .

6. The production method of aluminum according to claim 1 , wherein the halogenated aluminum hydrate is aluminum (III) chloride hexahydrate.

7. The production method of aluminum according to claim 1 , wherein the phosphorus compound is selected from the group consisting of phosphinic acid, a phosphine oxide, and tributyl phosphate.

8. The production method of aluminum according to claim 1 , wherein the organic compound having an amide group is selected from the group consisting of N-phenylacetamide, dimethylformamide, and dimethylacetamide.

Assignees

• Uacj Corp

Inventors

• NUNOMURA Junji
• Kojima Yoichi
• Ueda Mikito

Classifications

• C25D5/44

  Aluminium · CPC title

• C25D3/665 Primary

  from ionic liquids · CPC title

• C25C3/18 Primary

  Electrolytes · CPC title

• C25D3/44

  Aluminium · CPC title