Additive for high-purity copper electrolytic refining and method of producing high-purity copper

Patent metadata

Field	Value
Publication number	US-10793956-B2
Application number	US-201615248038-A
Country	US
Kind code	B2
Filing date	Aug 26, 2016
Priority date	Aug 29, 2015
Publication date	Oct 6, 2020
Grant date	Oct 6, 2020

Abstract

The present invention provides an additive for high-purity copper electrolytic refining and a method of producing high-purity copper using the additive. The additive of the present invention for high-purity copper electrolytic refining can be added to a copper electrolyte in electrolytic refining for producing high-purity copper. The additive includes a main agent formed of a non-ionic surfactant which has a hydrophobic group containing an aromatic ring and a hydrophilic group containing a polyoxyalkylene group, and a stress relaxation agent formed of a polyvinyl alcohol or a derivative thereof.

First claim

What is claimed is:

1. An additive for high-purity copper electrolytic refining which is an additive to be added to a copper electrolyte in electrolytic refining for producing high-purity copper, the additive consisting essentially of:
a main agent formed of a non-ionic surfactant which has a hydrophobic group containing an aromatic ring and a hydrophilic group containing a polyoxyalkylene group; and
a stress relaxation agent formed of a polyvinyl alcohol or a derivative thereof,
wherein the main agent is one or more selected from the group consisting of compounds represented by Formulae [1] and [2],

where n of Formulae [1] and [2] is an added number of moles of a polyoxyethylene group, and n is 2 to 20.

2. The additive for high-purity copper electrolytic refining according to claim 1 ,
wherein the stress relaxation agent is a polyvinyl alcohol which has a saponification rate of 70 to 99% by mole and has an average polymerization degree of 200 to 2500 or a derivative thereof.

3. The additive for high-purity copper electrolytic refining according to claim 2 ,
wherein the polyvinyl alcohol derivative is a carboxy-modified polyvinyl alcohol, an ethylene-modified polyvinyl alcohol, or a polyoxyethylene-modified polyvinyl alcohol.

4. The additive for high-purity copper electrolytic refining according to claim 1 ; wherein the main agent is one or more selected from the group consisting of compounds represented by Formulae [1]:

5. The additive for high-purity copper electrolytic refining according to claim 1 ; wherein the main agent is one or more selected from the group consisting of compounds represented by Formulae [2]:

6. A method of producing high-purity copper, comprising:
performing copper electrolysis using a copper electrolyte to which a main agent and a stress relaxation agent are added, the main agent being formed of a non-ionic surfactant which has a hydrophobic group containing an aromatic ring and a hydrophilic group containing a polyoxyalkylene group, and the stress relaxation agent being formed of a polyvinyl alcohol or a derivative thereof,
wherein the main agent is one or more selected from the group consisting of compounds represented by Formulae [1] and [2],

where n of Formulae [1] and [2] is an added number of moles of a polyoxyethylene group, and n is 2 to 20.

7. The method of producing high-purity copper according to claim 6 ,
wherein the copper electrolysis is performed such that the concentration of the main agent is 2 to 500 mg/L and the concentration ratio (Y/X) of the stress relaxation agent (Y) to the main agent (X) is in a range of 0.01 to 1.0 in the copper electrolyte.

8. The method of producing high-purity copper according to claim 7 ,
wherein the copper electrolyte is a copper sulfate solution, a copper nitrate solution, or a copper chloride solution.

9. The method of producing high-purity copper according to claim 7 ,
wherein the copper electrolyte has a copper concentration of 5 to 90 g/L and is one of a copper sulfate solution which has a sulfuric acid concentration of 10 to 300 g/L, a copper nitrate solution which has a nitric acid concentration of 0.1 to 100 g/L, and a copper chloride solution which has a hydrochloric acid concentration of 10 to 300 g/L.

10. The method of producing high-purity copper according to claim 7 ,
wherein high-purity copper is produced in which both of the sulfur concentration and the silver concentration are 1 ppm by mass or less and the glossiness on the surface of electrolytic copper is 1 or greater.

11. The method of producing high-purity copper according to claim 6 ,
wherein the copper electrolyte is a copper sulfate solution, a copper nitrate solution, or a copper chloride solution.

12. The method of producing high-purity copper according to claim 11 ,
wherein the copper electrolyte has a copper concentration of 5 to 90 g/L and is one of a copper sulfate solution which has a sulfuric acid concentration of 10 to 300 g/L, a copper nitrate solution which has a nitric acid concentration of 0.1 to 100 g/L, and a copper chloride solution which has a hydrochloric acid concentration of 10 to 300 g/L.

13. The method of producing high-purity copper according to claim 11 ,
wherein high-purity copper is produced in which both of the sulfur concentration and the silver concentration are 1 ppm by mass or less and the glossiness on the surface of electrolytic copper is 1 or greater.

14. The method of producing high-purity copper according to claim 6 ,
wherein the copper electrolyte has a copper concentration of 5 to 90 g/L and is one of a copper sulfate solution which has a sulfuric acid concentration of 10 to 300 g/L, a copper nitrate solution which has a nitric acid concentration of 0.1 to 100 g/L, and a copper chloride solution which has a hydrochloric acid concentration of 10 to 300 g/L.

15. The method of producing high-purity copper according to claim 14 ,
wherein high-purity copper is produced in which both of the sulfur concentration and the silver concentration are 1 ppm by mass or less and the glossiness on the surface of electrolytic copper is 1 or greater.

16. The method of producing high-purity copper according to claim 6 ,
wherein high-purity copper is produced in which both of the sulfur concentration and the silver concentration are 1 ppm by mass or less and the glossiness on the surface of electrolytic copper is 1 or greater.

Assignees

• Mitsubishi Materials Corp

Inventors

• Kubota Kenji
• Tarutani Yoshie
• Nakaya Kiyotaka

Classifications

• C25C1/12 Primary

  of copper · CPC title