Apparatus for electrolytic etching and dissolution and method for extracting metal compound particles

Patent metadata

Field	Value
Publication number	US-2020141843-A1
Application number	US-201715999791-A
Country	US
Kind code	A1
Filing date	Feb 17, 2017
Priority date	Feb 18, 2016
Publication date	May 7, 2020
Grant date	—

Abstract

The object of the present invention is such that a surface exchange of metal fine particles by Cu ions, or the like is inhibited in order to prevent formation of Artificial CuS or the like, in extraction and analysis of the metal fine particles (inclusions and precipitates) in a metal material by electrolytic corrosion in a solvent-based electrolytic solution, without significantly changing conventional extraction and analysis methods, and such that the metal deposited on the cathode is actively attached to the cathode so that the deposited metal does not become a contamination source.
An apparatus for electrolytic etching and dissolution and an extraction method for separation and extraction of metal compound particles in a metal material,
wherein at least a part of the cathode comprises a material consisting of a metal M′ whose Δ defined by the following formula is 10 or more, and the apparatus comprises an electrolytic cell for containing an electrolytic solution comprising a chemical agent that forms a complex containing the metal M′ and a nonaqueous solvent,

Δ
=

pKsp


[

M
′



x
′



Ay
′

]

-

pKsp


[
MxAy
]

=

(

-

log
10



Ksp


[

M
′



x
′



Ay
′

]

)

-

(

-

log
10



Ksp


[
MxAy
]

)

.

First claim

1 . An apparatus for electrolytic etching and dissolution for separation and extraction of metal compound particles in a metal material, the apparatus comprising an anode and a cathode, and electrolytically etching the metal material by electrifying between the anode and the cathode,
wherein at least a part of the cathode comprises a material comprising a metal M′ whose Δ defined by the following formula is 10 or more, and the apparatus comprises an electrolytic cell for containing an electrolytic solution comprising a chemical agent that forms a complex containing said metal M′ and a nonaqueous solvent,

Δ
=

pKsp


[

M
′



x
′



Ay
′

]

-

pKsp


[
MxAy
]

=

(

-

log
10



Ksp


[

M
′



x
′



Ay
′

]

)

-

(

-

log
10



Ksp


[
MxAy
]

)

wherein a solubility product of metal compound M′x′Ay′ is defined as Ksp[M′x′Ay′], and a solubility product of metal compound to be extracted MxAy, which is contained in the metal material, is defined as Ksp[MxAy], and
wherein M and M′ are different metal elements, A is a single atom or atomic group forming a compound with M or M′, and x, x′, y and y′ represent a composition ratio of the compound determined according to the valences of M, M′ and A, and the solubility product Ksp is a value in an aqueous solution at 25° C.

2 . The apparatus for electrolytic etching and dissolution according to claim 1 , wherein the metal compound to be extracted MxAy is one or two of MnS or FeS.

3 . The apparatus for electrolytic etching and dissolution according to claim 1 or 2 , wherein the metal M′ of the metal compound M′x′Ay′ is at least one of Hg, Ag, Cu, Pb, Cd, Co, Zn and Ni.

4 . The apparatus for electrolytic etching and dissolution according to any one of claims 1 to 3 , wherein said material comprised in the cathode is provided to cover a surface of the cathode.

5 . The apparatus for electrolytic etching and dissolution according to any one of claims 1 to 3 , wherein the cathode is made of said metal M′.

6 . The apparatus for electrolytic etching and dissolution according to any one of claims 1 to 5 , wherein said material comprised in the cathode consists of 99.9% by mass or more of Cu and inevitable impurities.

7 . The apparatus for electrolytic etching and dissolution according to any one of claims 1 to 6 , wherein said nonaqueous solvent comprises at least one of methanol or ethanol.

8 . The apparatus for electrolytic etching and dissolution according to any one of claims 1 to 7 , wherein the chemical agent that forms a complex containing the metal M′ comprises at least one of polyethylene amines, ethylenediamine tetraacetic acid and cyclohexanediamine tetraacetic acid.

9 . The apparatus for electrolytic etching and dissolution according to claim 8 , wherein the chemical agent comprises triethylenetetramine.

10 . The apparatus for electrolytic etching and dissolution according to any one of claims 1 to 9 , wherein it comprises a stirring means for the electrolytic solution.

11 . The apparatus for electrolytic etching and dissolution according to claim 10 , wherein it further comprises a gas bubble generator for irradiating a bubble to the anode surface.

12 . A method for extracting metal compound particles in a metal material, by providing an anode and a cathode, and electrolytically etching the metal material by electrifying between the anode and the cathode,
wherein at least a part of the cathode comprises a material comprising a metal M′ whose Δ defined by the following formula is 10 or more, and the method uses an electrolytic solution comprising a chemical agent that forms a complex containing said metal M′ and a nonaqueous solvent,

Δ
=

pKsp


[

M
′



x
′



Ay
′

]

-

pKsp


[
MxAy
]

=

(

-

log
10



Ksp


Assignees

• Nippon Steel & Sumitomo Metal Corp

Inventors

• Mizukami Kazumi

Classifications

• G01N33/2028

  Metallic constituents · CPC title

• C25F3/02 Primary

  Etching · CPC title

• C25F3/06

  of iron or steel · CPC title

• G01N1/32 Primary

  Polishing; Etching · CPC title

• G01N1/40

  Concentrating samples · CPC title