JP3242289B2 - Method for treating iron chloride solution containing copper and nickel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for regenerating a solution containing ferric chloride containing a copper component and a nickel component as a main component.

[0002]

2. Description of the Related Art When both nickel or a nickel alloy and copper or a copper alloy are treated with an etching solution containing ferric chloride as a main component, as the etching progresses, the respective metals are removed. Nickel and copper are eluted, and the etching ability of the liquid gradually decreases, resulting in a waste liquid which is finally difficult to use.

From the viewpoints of economy and resource saving, it is desirable to regenerate and recycle the etching waste liquid, and the present applicant has disclosed, for example, Japanese Patent Application Laid-Open No. 5-125564 for a ferric chloride solution containing copper. In the gazette, as a diaphragm electrolysis treatment, it is proposed to regenerate the solution by using chlorine gas generated on the anode side as an oxidizing agent while depositing copper on the cathode side where the metal ion concentration is adjusted. Japanese Patent Application Laid-Open No. 6-240475 also proposes regeneration of the ferric chloride solution containing nickel based on the diaphragm electrolysis method.

[0004] However, no effective treatment method has been established for waste liquid containing both components of copper and nickel. In view of the above two proposals, it is also possible to regenerate the waste liquid by a one-stage diaphragm electrolysis method.
The recovered metal is a mixture of copper, nickel, iron and their alloys, and the value at the time of recycling is lower than in the case where it has been separated in advance.The lower the copper concentration and nickel concentration in the regenerating solution, the lower the regenerating solution In particular, when a regenerant is used for etching a nickel-iron-based material, the concentration of the copper component needs to be 20 ppm or less. Therefore, when the anode-side liquid is used as the regenerating liquid as in the conventional case, it is convenient to lower the concentration of the nickel component, but the concentration of the copper component is insufficient.

Accordingly, the present invention reduces the concentrations of the copper component and the nickel component in a ferric chloride-based solution containing a copper component and a nickel component as much as possible and increases the use value of the precipitated metal. An object of the present invention is to provide a method for regenerating an iron chloride solution.

[0006]

The present invention solves the above problems,
An iron chloride solution containing copper and nickel is supplied to the cathode side of the first membrane electrolytic cell to perform electrolytic reduction, and after reducing and depositing a copper component, a copper-removing solution is supplied to the second membrane electrolytic cell. The problem is solved by reducing and precipitating a nickel component.

As a result of extensive studies by the present inventors, when an iron chloride solution containing a copper component and a nickel component is subjected to diaphragm electrolysis, iron ions and copper ions are easily moved to the anode side by electrophoresis, and nickel ions Was found to be easily moved to the cathode side. The reason is not clear,
In the case of divalent iron, trivalent iron, monovalent copper, and divalent copper, the ratio of negative charges as various complex ions is higher than the ratio of dissociation as a single cation. It is presumed to be the opposite. Therefore, the present invention utilizes such a phenomenon to effectively remove the copper component and the nickel component of the iron chloride solution containing the copper component and the nickel component, and the electrolytic treatment is performed in two stages. The outline is to do. In each electrolytic treatment, it is preferable to use an electrolytic tank having an electrically neutral diaphragm having a small electric resistance, such as modacrylic, vinyl acetate, polyester, and vinylidene chloride. When supplying the liquid after the electrolytic treatment in the first electrolytic cell to the second electrolytic cell, the amount of the supplied liquid is adjusted so that the liquid composition in the electrolytic cell becomes constant, for example, by controlling the specific gravity. It is preferable to supply to the cathode side and the anode side at an appropriate ratio in accordance with the concentration change accompanying the electrodeposition and the ion movement through the diaphragm, but it is also possible to supply to only the cathode side.

[0008] With respect to the copper component, only 20%
It is practically difficult to continuously obtain a regenerating solution of not more than ppm. Therefore, when it is necessary to reduce the copper concentration as much as possible, the electrolytic treatment solution after reducing and precipitating the copper component in the first diaphragm electrolyzer is brought into contact with an iron material so as to further remove the remaining copper. Is also good. Regarding the properties of the deposited metal, copper is a non-adhesive powder, whereas nickel-iron alloy is likely to be unstable due to adhesion,
Recovery is not relatively easy. Furthermore, 500ppm only by electrolysis
Below, lowering the nickel concentration also increases costs.
Therefore, the electrolytic treatment solution obtained by reducing and precipitating the copper component in the first diaphragm electrolytic cell may be brought into contact with an iron material, and the nickel component may be removed at the stage of the iron substitution process with the nickel component together with the remaining copper. That is, an iron chloride solution containing copper and nickel is supplied to the cathode side of the first diaphragm electrolyzer and electrolytically reduced to reduce and precipitate a copper component. Then, the reduction treatment solution is brought into contact with an iron material and contained in the solution. Copper and nickel to be reduced and precipitated, and then the iron replacement treatment liquid is supplied to a second diaphragm electrolytic cell,
The above problem can also be effectively solved by reducing and depositing iron on the cathode side.

As the iron material used in the substitution reaction, it is preferable to use iron powder which can be easily handled and has a large contact area. For example, the particle size is preferably 100 mesh passes or more, and more preferably 150 to 350 mesh passes. Further, when the specific surface area is 1 m ² / g or more, nickel removal efficiency increases, which is preferable.

If chlorine gas generated on the anode side of the first diaphragm electrolytic cell is used as an oxidizing agent and is brought into contact with the solution after the electrolytic treatment, it is possible to effectively use all the substances related to the electrolytic process. It is preferable because it can be performed.

[0011]

The present invention will be described more specifically with reference to the following examples. (Example 1) As shown in FIG.
2.3 g / l, trivalent iron component 130 g / l, nickel component 8.6 g / l, divalent copper component 2
29.2 liters of a waste liquid having a composition of 2.6 g / liter and a chlorine component of 382 g / liter and a specific gravity of 1.423 is supplied to the cathode chamber (cathode: titanium plate) of the first membrane electrolytic cell 1 having a membrane of polyester filter cloth. / Hour, constant current supply, current 300
Electrolysis was performed at 0 A (constant current) and a voltage of 3.2 V. The composition of the copper removal liquid withdrawn at 29.2 liters / hour from the cathode chamber was 182 g / liter of divalent iron component, less than 0.5 g / liter of trivalent iron component, 8.6 g / liter of nickel component, Valent copper component 0.2g / l, chlorine component 25
It was 4 g / liter.

From the cathode chamber of the first diaphragm electrolytic cell, 653.6 g / hour of copper powder removed from the cathode plate was recovered, and chlorine was collected from the anode chamber (anode: RuO ₂ / Ti net (DSA electrode)). Since the gas was generated at 3735 g / h, the gas was led to the absorption tower 3.

The above-mentioned copper removal liquid is used in a second electrolytic cell having the same structure as the first electrolytic cell.
A constant amount of 24.8 liters / hour and 4.4 liters / hour were supplied to the cathode chamber and the anode chamber of the diaphragm electrolyzer 2 respectively. Current 2
2,000 A (constant current), electrolysis at a voltage of 3.2 V, and 29.2
The composition of the liquid extracted at a rate of 1 liter / hour is as follows.
2.3 g / L, trivalent iron component 120.3 g / L, nickel component 2.0 g / L, divalent copper component 0.09 g / L, and chlorine component 254 g / L. 1634g / iron / nickel alloy from cathode plate
It was peeled and collected at times. Its composition was 88.2% iron and 11.6% nickel.

The nickel-removed solution passed through the second diaphragm electrolyzer 2 was led to the absorption tower 3 and was brought into contact with chlorine gas generated in the first diaphragm electrolyzer 1. When the divalent iron component was less than 0.5 g / liter, A regenerating solution containing 132.6 g / liter of a trivalent iron component, 2.0 g / liter of a nickel component, 0.09 g / liter of a divalent copper component, and 262 g / liter of a chlorine component was obtained.

Example 2 As shown in FIG. 2, 52.3 g / liter of divalent iron component and 130 g of trivalent iron component
1 / liter, nickel component 8.6 g / l, divalent copper component 22.6 g / l, chlorine component 382 g / l, wastewater having a specific gravity of 1.423 are the same as those in the diaphragm electrolytic cell in the embodiment of FIG. A constant amount of 29.2 liters / hour was supplied to the cathode chamber of the first diaphragm electrolytic cell 1 having
Electrolysis was performed at 0 A (constant current) and a voltage of 3.2 V. The composition of the copper removal liquid withdrawn at 29.2 liters / hour from the cathode chamber was 182 g / liter of divalent iron component, less than 0.5 g / liter of trivalent iron component, 8.6 g / liter of nickel component, Valent copper component 0.2g / l, chlorine component 25
It was 4 g / liter.

The copper powder removed from the cathode plate was recovered at 653.6 g / hour from the cathode chamber of the first diaphragm electrolytic cell, and chlorine gas was generated at 3735 g / hour from the anode chamber. It led to absorption tower 3.

The electrolytic solution of the first diaphragm electrolyzer is replaced with an iron-substitute tank 4.
Led to. The iron replacement tank 4 is a column filled with iron powder, and is prepared as a batch of 500 liters in a batch operation of about 0.5.
kg / batch of iron powder. The liquid composition after the reaction at a liquid temperature of 50 ° C. is 184 g / liter of a bivalent iron component,
The trivalent iron component was less than 0.5 g / liter, the nickel component was 8.5 g / liter, and the copper component was less than 5 mg / liter. Further, 5.9 g / hour of metallic copper powder was precipitated in the iron powder of the column.

The above-mentioned iron-substituted solution is placed in a cathode chamber and an anode chamber of a second diaphragm electrolytic cell 2 having the same structure as the first electrolytic cell, respectively.
The fixed amount was supplied at 4.8 liter / hour and 4.4 liter / hour. Electrolysis at a current of 2000 A (constant current) and a voltage of 3.2 V, and the composition of the solution extracted from the anode chamber at 29.2 liter / hour has a composition of divalent iron component of 11.9 g / liter and trivalent iron component of 121. 3 g / liter, nickel component 2.1 g /
Liter, divalent copper component was less than 5 mg / liter, and chlorine component was 256 g / liter. Iron from the cathode plate 87.
1% iron-nickel alloy consisting of 5% and 11.9% nickel
Peeling and recovery were performed at 625 g / hour.

The liquid having passed through the second diaphragm electrolytic cell 2 was led to the absorption tower 3 and brought into contact with chlorine gas generated in the first diaphragm electrolytic cell 1. When the divalent iron component was less than 0.5 g / liter, 133.2 g / liter of iron component, 2.1 g of nickel component
/ Liter, a regenerating liquid having a divalent copper component of less than 5 mg / liter and a chlorine component of 264 g / liter was obtained.

Example 3 As shown in FIG. 2, 52.3 g / liter of divalent iron component and 130 g of trivalent iron component
1 / liter, nickel component 8.6 g / l, divalent copper component 22.6 g / l, chlorine component 382 g / l, wastewater having a specific gravity of 1.423 are the same as those in the diaphragm electrolytic cell in the embodiment of FIG. A constant amount of 29.2 liters / hour was supplied to the cathode chamber of the first diaphragm electrolytic cell 1 having
Electrolysis was performed at 0 A (constant current) and a voltage of 3.2 V. The composition of the copper removal liquid withdrawn at 29.2 liters / hour from the cathode chamber was 182 g / liter of divalent iron component, less than 0.5 g / liter of trivalent iron component, 8.6 g / liter of nickel component, Valent copper component 0.2g / l, chlorine component 25
It was 4 g / liter.

From the cathode chamber of the first diaphragm electrolyzer, 653.6 g / hour of copper powder washed off from the cathode plate was recovered, and chlorine gas was generated at 3735 g / hour from the anode chamber. It led to absorption tower 3.

The electrolytic treatment solution in the first diaphragm electrolyzer is replaced with an iron replacement
Led to. In this iron displacement tank 4, a batch was made up to 500 liters and brought into contact with about 20 kg / batch of iron powder by batch operation. The liquid composition after reacting and filtering at a liquid temperature of 65 ° C. with stirring has a divalent iron component of 198 g / liter, a trivalent iron component of 0.5 g / liter, a nickel component of 160 mg / liter, and a divalent copper component of 10 mg. / Liter. Further, 1200 g / hour of iron powder containing nickel composed of 77.5% of iron and 20.5% of nickel was obtained.

The above-mentioned iron-substituted solution was supplied at a constant rate of 29.2 liters / hour to the cathode chamber of the second diaphragm electrolytic cell 2 having the same structure as the first electrolytic cell. 2. Current 2000A (constant current), voltage 3.
The composition of the solution electrolyzed at 2 V and withdrawn from the anode chamber at 29.2 liters / hour was 12.5 g / liter of a divalent iron component, 122.3 g / liter of a trivalent iron component, 160 mg / liter of a nickel component, The divalent copper component was 10 mg / liter and the chlorine component was 254 g / liter. Electrolytic iron was separated and recovered from the cathode plate at 1850 g / hour.

The liquid passed through the second diaphragm electrolytic cell 2 was led to the absorption tower 3 and brought into contact with chlorine gas generated in the first diaphragm electrolytic cell 1. When the divalent iron component was less than 0.5 g / liter, 134.8 g / liter of iron component, 160 m of nickel component
g / liter, a regenerating liquid having a divalent copper component of 10 mg / liter and a chlorine component of 262 g / liter was obtained.

[0025]

The first aspect of the present invention is suitable for a case where the concentration of residual copper in the regenerating solution is acceptable to a certain extent, whereby the iron chloride solution containing copper and nickel can be used in the first diaphragm electrolysis. It is supplied to the cathode side of the cell and electrolytically reduced to reduce and precipitate the copper component. Then, the copper removal solution is treated in the second diaphragm electrolyzer, and the nickel component is reduced and precipitated at the cathode side. Can be electrolytically deposited in accordance with the properties of each metal attracted to each of them, and the value at the time of recycling can be enhanced.

The invention described in claim 2 is suitable when the copper concentration in the regenerating solution needs to be 20 mg / liter or less and the nickel concentration is acceptable even if it is somewhat high. (1) The electrolytic treatment solution after electrolytic reduction in the diaphragm electrolyzer is brought into contact with an iron material to reduce and precipitate the copper remaining in the solution, and then the copper removal solution is supplied to the second diaphragm electrolyzer. It is possible to achieve the same effect as in claim 1 while lowering the level to an extremely low level.

According to the third aspect of the invention, an iron chloride solution containing copper and nickel is supplied to the cathode side of the first diaphragm electrolytic cell and electrolytically reduced to reduce and deposit a copper component. The solution is brought into contact with an iron material to reduce and precipitate residual copper and nickel contained in the solution, and thereafter, the iron replacement treatment solution is treated in a second diaphragm electrolytic tank, and iron is reduced and precipitated on the cathode side. Can increase the value of metal recycling.
Metal recovery during the treatment can be performed relatively easily, and the copper and nickel concentrations in the regenerating solution can be reduced to the same level as the new solution.

According to the fourth aspect of the present invention, the chlorine gas generated on the anode side of the first diaphragm electrolytic cell is brought into contact with the solution after the electrolytic treatment as an oxidizing agent, so that all substances related to the electrolytic process can be effectively used. It can be used, and the liquid can be effectively regenerated.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram illustrating a processing step according to the present invention.

FIG. 2 is a conceptual diagram illustrating processing steps according to the invention of a process different from that of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st diaphragm electrolysis tank 2 2nd diaphragm electrolysis tank 3 Absorption tower 4 Iron substitution tank

────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Mikami Yasushiya 2-1 Hirai-cho, Hinode-cho, Nishitama-gun, Tokyo Nippon Steel Mining Co., Ltd. (72) Inventor Masayoshi Kato 1 Kosugaya, Sakae-ku, Yokohama-shi, Kanagawa Prefecture -11-2 (56) References JP-A-7-278849 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C23F 1/46 C02F 1/461 C02F 1/72 ZAB

Claims (4)

(57) [Claims] 1. An iron chloride solution containing copper and nickel is supplied to a cathode side of a first diaphragm electrolytic cell to perform electrolytic reduction to reduce and precipitate a copper component, and then supply a decoppered liquid to a second diaphragm electrolytic cell. Then, a nickel component is reduced and precipitated on the cathode side. 2. After the electrolytic reduction in the first diaphragm electrolytic cell,
2. The method according to claim 1, wherein the electrolytic treatment solution is brought into contact with an iron material to reduce and precipitate copper remaining in the solution, and then the copper removal solution is supplied to the second diaphragm electrolytic cell. 3. An iron chloride solution containing copper and nickel is supplied to the cathode side of the first diaphragm electrolysis tank to perform electrolytic reduction, to reduce and precipitate a copper component, and then contact the electrolytic treatment solution with an iron material to cause the electrolytic treatment. A method in which residual copper and nickel contained therein are reduced and precipitated, and thereafter, the iron replacement treatment liquid is supplied to a second diaphragm electrolytic cell, and iron is reduced and precipitated on the cathode side. 4. The method according to claim 1, wherein chlorine gas generated on the anode side of the first diaphragm electrolytic cell is brought into contact with the solution after the electrolytic treatment as an oxidizing agent. Method.