KR101247941B1 - Refining Method of Copper Chloride Etching Waste Fluid And Refined Copper Chloride Solution - Google Patents

Abstract

An object of the present invention is to remove and purify an impurity metal other than copper which is an effective metal for the copper chloride etching waste liquid after etching the copper material in a simple operation and at low cost.

It is known that anionic complexes of metals such as zinc, iron and the like are removed by contacting the weakly basic anion exchange resin. On the other hand, although copper, which is an effective metal in copper chloride etching waste liquid, is known to exist as an anionic complex, the present inventors have found that copper anionic complex in copper chloride etching waste liquid hardly adsorbs when contacted with a strong or weakly basic anion exchange resin. Therefore, by contacting the copper chloride etching waste liquid with these anion exchange resins, the anionic complexes of iron and zinc are adsorbed and removed from the resin, but the copper chloride etching waste liquid can be purified because copper remains in the liquid as it is.

Copper chloride etching complex, anion exchange resin, loading core tank, waste water tank

Description

Refining Method of Copper Chloride Etching Waste Fluid And Refined Copper Chloride Solution

BRIEF DESCRIPTION OF THE DRAWINGS The block diagram which shows an example of the apparatus for implementing the refinement | purification method of the copper chloride etching waste liquid which concerns on this invention.

2 is an explanatory diagram showing the results of experiments conducted to confirm the effects of the present invention.

3 is an explanatory diagram showing the results of experiments conducted to confirm the effects of the present invention.

4 is an explanatory diagram showing the results of experiments conducted to confirm the effects of the present invention.

5 is an explanatory diagram showing the results of experiments conducted to confirm the effects of the present invention.

6 is an explanatory diagram showing the results of experiments conducted to confirm the effects of the present invention.

<Explanation of symbols for main parts of the drawings>

1: copper chloride etching waste tank

2: refinery tower

21: adsorption layer consisting of a strong basic anion exchange resin

3: refining liquid tank

4: pure water tank

5: wastewater tank

[Document 1] Japanese Unexamined Patent Publication No. 2004-299974

[Document 2] Japanese Unexamined Patent Publication No. 2003-265902

[Document 3] Japanese Unexamined Patent Application Publication No. 5-179465

[Document 4] Japanese Unexamined Patent Publication No. Hei 8-81719

The present invention relates to a method for purifying a copper chloride etching waste liquid after etching the copper material, and a copper chloride solution obtained by the purification method.

BACKGROUND OF THE INVENTION An etching method of a copper printed circuit board with a cupric chloride etching solution is generally used in a wide range of fields such as civilian use and industrial equipment. With this etching solution shown by the equation (1) to the reaction mechanism is that the etching process the copper foil is etched recognition, cupric (CuCl ₂₎ chloride by the reaction is a first copper chloride (CuCl).

[Formula 1]

Cu + CuCl ₂ → 2CuCl

Since the produced cupric chloride lowers the etching rate, for example, hydrogen peroxide and hydrochloric acid are added to the etching solution, and the cupric chloride is regenerated to cupric chloride by the following regeneration reaction. .

[Formula 2]

2CuCl + H ₂ O ₂ + 2HCl → 2CuCl ₂ + 2H ₂ O

The etchant can perform such a regeneration treatment, but the etchant increases to become a surplus. However, this surplus, i.e., copper chloride etching waste, has a high copper concentration, and thus has high utility as a raw material for copper materials. For example, a raw material of copper carbonate or copper oxide as a copper replenisher used for electrolytic copper plating using an insoluble anode. Can be Copper carbonate is produced by mixing the copper chloride etching waste solution with an aqueous solution containing carbonate ions, for example, an aqueous sodium carbonate solution while heating, and copper oxide can be obtained by thermal decomposition of copper carbonate. Thus, the method of manufacturing copper replenishment material using copper chloride etching waste liquid can utilize the waste liquid effectively, and it is advantageous in cost compared with the case of commercially available basic copper carbonate raw material. In addition, when sodium carbonate is used as a chemical agent to obtain copper carbonate or copper oxide, the generated wastewater becomes an aqueous sodium chloride solution, and the copper chloride etching waste liquid can be said to be a raw material that is easy to handle from the point of wastewater treatment.

By the way, in a copper chloride etching waste liquid, an etching target material, for example, a copper thin plate elutes at the time of etching, and the impurity metal contained in the copper foil is blown into the etching liquid. Moreover, since copper chloride etching waste liquid is highly corrosive, it is also considered that impurity metal is blown in at the time of conveyance of a liquid. For this reason, when an etching waste liquid is used as a raw material, the impurity metal mentioned above mixes in the obtained copper refill material. When this copper replenishment material is supplied to the plating bath, impurity metal accumulates in the plating bath, and the concentration thereof becomes high. In fact, when analyzing copper chloride etching waste liquid, iron (Fe), zinc (Zn), aluminum (Al), etc. are contained, and it turns out that iron and zinc concentration is high especially. As for iron, since it is hardly contained in the printed board, the mixing route is not clear, but it may have started to melt from the inner wall surface when the copper chloride etching waste liquid is stored in the tank or conveyed by the tank roller. I guess. However, it is known that the copper plating film becomes rough when the concentration of impurity metals, especially iron and zinc, in the plating bath is increased.

Copper oxide is also used as a glaze, but when iron is contained, the color tone after firing becomes unstable. From this situation, it is necessary to purify the copper chloride etching waste solution to remove impurities. Patent Literature 1 adds a chloride and a metal copper material of an alkali metal or an alkaline earth metal to the copper chloride etching waste solution to generate cuprous chloride, and this solution It is described that after removing the insoluble residue from the solution, water is added to the mother liquor to precipitate cuprous chloride, and chlorine gas is supplied into the water in which cupric chloride is soaked to obtain cupric chloride aqueous solution. However, this technique has a problem that operation is cumbersome and operation costs are high.

Further, Patent Document 2 describes that anionic complexes can be removed by contacting a solution containing an anionic complex of zinc or iron with a weakly basic anion exchange resin under a condition of pH 3 or more and 7 or less. There is no suggestion about the purification of the waste liquid.

Patent Literature 3 also discloses a copper chloride etching solution after the etching treatment through an anion (anion) exchange resin to adsorb copper anionic complex ions in the liquid to the resin, and subsequently removes copper ions from the resin to recover copper. It is described. It is also described that the resin is broken through by immersing the salt copper liquid twice as much as the resin volume. In general, however, considering that the liquid discharged at the beginning of the liquid passage contains a lot of water coexisting for the purpose of hydration of the ion exchange resin, this technique is excessive in the amount of liquid until the anion exchange resin reaches breakthrough. Since it is short, it considers and evaluates by the analysis result of the water or the processing liquid diluted with the water. Therefore, the perception of breakthrough of the anion exchange resin is wrong, and accurate experiments on copper adsorption on the anion exchange resin have not been conducted, and no knowledge on solving the problem of the present invention has been suggested.

In addition, Patent Literature 4 discloses 1 kg of coarse copper powder in a mixture of 50 liters of hydrochloric acid and 15 liters of hydrogen peroxide, and dissolves copper, and removes the remaining solids by self-adsorption. After adsorbing on, it is described that 9 M hydrochloric acid is subsequently passed through an anion exchange resin to elute nickel and chromium, and then 4.8 M hydrochloric acid is passed through to elute copper. However, this technique adsorbs copper to the anion exchange resin and subsequently removes the impurity metal and the copper in two stages, which is cumbersome to operate. In addition, since hydrochloric acid is used for the separation, the operation cost thereof is high. In addition, this patent document 4 relates to a liquid having a copper concentration of less than 1.5% by weight to separate copper by removing iron and zinc from a high copper chloride etching waste liquid having a copper concentration of, for example, 6% by weight or more. Not listed.

[Patent Document 1] Japanese Unexamined Patent Publication No. 2004-299974

[Patent Document 2] Japanese Unexamined Patent Publication No. 2003-265902: Paragraph 0007, 0012, 0013

[Patent Document 3] Japanese Patent Application Laid-Open No. 5-179465: Paragraphs 0001, 0011, 0012, and 0018

[Patent Document 4] Japanese Patent Application Laid-Open No. 8-81719: Claim 1, Paragraph 0031, 0032

This invention is made | formed in view of such a situation, Comprising: It aims at providing the method which can refine | purify a copper chloride etching waste liquid at low cost, and is easy to operate.

The present invention is a method of purifying a copper chloride etching waste liquid after etching the copper material to obtain a copper chloride solution,

The etching waste liquid is contacted with a weakly basic anion exchange resin or a strong basic anion exchange resin in a pH range where a solid component as a copper hydroxide is not produced, thereby adsorbing and removing impurity metal to the resin to obtain a purified copper chloride solution. It is done. The present inventors confirmed that the precipitation of copper hydroxide was observed when the pH of the copper chloride etching waste solution was 2 or more, and the precipitation was not seen when the pH was 1.5. Therefore, the present invention is less than 2 for the pH region where the solid component of copper hydroxide is not produced. It is certain that any value of 1.5 or more is the upper limit, but in the actual process, since the critical point of pH at which copper hydroxide precipitates are formed by temperature or stirring method is somewhat changed, the inventors of the present invention have a method of 1.5 or less. It is grasping that it can carry out, and considering the stability of a process, it is preferable that it is 1 or less. Moreover, as an impurity metal, it is iron and zinc, for example.

In order to make pH of a copper chloride etching waste liquid below 1, hydrochloric acid is used, for example. However, since copper chloride etching waste liquid generally contains hydrochloric acid, pH adjustment is unnecessary when pH is maintained at 1 or less by this hydrochloric acid.

Moreover, the copper chloride solution which concerns on this invention was obtained by refine | purifying the copper chloride etching waste liquid after etching the copper material by the method mentioned above.

Copper chloride etching waste liquid which is the object of purification in this invention uses the etching liquid which hydrochloric acid was added to the cupric chloride solution, and the excess generate | occur | produced by etching the etching target materials, such as a printed circuit board, and regenerating as mentioned above, for example. It is liquid. The etching reaction is as shown in the above formula (1), and therefore the composition of the copper chloride etching waste liquid is, for example, about 21% by weight of cupric chloride, about 8% by weight of free hydrochloric acid, and iron and zinc as other impurities. It is contained in trace amount. In the analysis of the present inventors, iron was in the range of several ppm to several hundred ppm, while zinc was in the range of 30 to 50 ppm.

As a weakly basic anion exchange resin which makes this waste liquid contact, for example, a styrene-type thing is used, Specifically, the brand name Unburite (registered trademark) IRA96SB made from Rohm & Haas Corporation, and DIAION (made by Mitsubishi Chemical Corporation) are made. Registered trademark) WA30 and the like. Moreover, as an anion exchange resin, a strong basic anion exchange water may be sufficient, In this case, a styrene type is used, for example, DIAION (trademark) PA316 by Mitsubishi Chemical Corporation is mentioned.

In order to purify the copper chloride etching waste liquid by contacting the above-mentioned resin, it is necessary that the pH of the waste liquid is 1 or less. According to the experiment of the present inventors, when pH is 2, precipitation of copper hydroxide, ie, cupric hydroxide [Cu (OH) ₂ ], is seen, and when pH is 1.5, precipitation of copper hydroxide is not seen. If copper is precipitated as a solid copper hydroxide, there is a fear that clogging of the resin tower or deterioration of the resin may occur, and the purification yield may also decrease. For this reason, when implementing the refinement | purification method of this invention, it is necessary to make pH into the area which does not produce hydroxide precipitation, for example, it is necessary to set it as 1.5 or less. Moreover, since a copper chloride etching waste liquid generally has a pH lower than 1, it can be processed as it is. However, when alkali is mixed in the waste liquid by the etching maker and the pH becomes 1.5 or more, hydrochloric acid or the like is added to adjust the pH to 1.5 or less, for example.

In addition, although the inventor performed experiment in the range of 20 degreeC thru | or 60 degreeC with respect to processing temperature, and grasped | ascertained that there is no difference in a purification result, the temperature range is not specifically limited.

However, when the temperature rises to high temperature, hydrochloric acid mist is generated from the copper chloride etching waste solution, which causes a problem of worsening the working environment. Therefore, the process in 60 degrees C or less is preferable. Moreover, when the exchange group of an anion exchange resin is OH type, there exists a possibility that HCl will also be ion-exchanged. When there is a trace amount of HCl in the waste liquid, the pH is raised by this ion exchange, and the same aquatic product is generated. Therefore, in the case of using an OH-type resin, the resin is immersed in dilute hydrochloric acid as a pretreatment, so that the Cl is not ion-exchanged with HCl.

Next, an example of the purification apparatus for implementing the method of the present invention is shown in FIG. Reference numeral 1 denotes a copper chloride etching storage liquid tank, and the waste liquid stored therein is transferred to the purification tower 2 serving as a purification unit via a waste liquid supply pipe 11 serving as a waste liquid supply passage by a pump P1. In the purification tower 2, the adsorption layer 21 which consists of strong or weakly basic anion exchange resin is provided. About the specific structure of this adsorption layer 21, the spherical exchange resin of about 0.5 mm in diameter flows into the refiner tower 2 with water etc., and is laminated | stacked on the resin net installed in the refiner tower 2, have. Since the scale of this net is smaller than the diameter of exchange resin, exchange resin does not flow out downstream.

By controlling the pump P1, the waste liquid flows down inside the purification column 2 at a set space velocity (air column velocity). The waste liquid penetrates into the resin layer and comes into contact with the resin to purify as described above, and the copper chloride solution (copper chloride solution), which is a purified liquid, is transferred into the purification liquid tank 3 through the discharge pipe 22 as the discharge path. do. This refining liquid is then transferred by a pump P2 to a processing zone, for example a production apparatus of copper carbonate.

Then, the throughput of the waste liquid capable of sufficiently exhibiting the adsorption capacity of the adsorption layer 21 is checked, and the pump P1 is stopped by, for example, time management to determine that the throughput has been reached. Subsequently, the pure water in the pure water tank 4 is transferred by the pump P3 to the purification tower 2 as the cleaning liquid via the supply pipe 41 serving as the pure water supply path and adsorbed to the adsorption layer 21. The metal is washed and removed to restore the adsorption capacity of the anion exchange resin. The washing liquid discharged from the purification tower 2 is transferred to the drainage tank 5, and this washing waste water is transferred to the wastewater treatment facility by the pump P4. V1 to V9 are valves, and switching between supply of waste liquid to the purification tower 2 and supply of pure water is carried out by valves V2 and V4, to feed the purification liquid from the purification tower 2 and to the cleaning liquid. Is switched by switching the valves V6 and V7.

The copper chloride solution which is the purification liquid obtained in this way is used as a raw material of copper plating material (copper replenishment material), for example. Examples of copper plating materials include copper carbonate and copper oxide. When producing copper carbonate, a copper chloride solution and an aqueous solution containing carbonate ions, for example, an aqueous sodium carbonate solution are mixed and heated, and the reaction product. The powder of basic copper carbonate can be obtained by filtering and wash | cleaning this. Moreover, when manufacturing copper oxide, it can obtain by heating and pyrolyzing the powder of basic copper carbonate.

According to the embodiment described above, since impurity metals such as iron and zinc in the copper chloride etching waste liquid are adsorbed to the anion exchange resin and most of the copper remains in the waste liquid, the copper chloride etching waste liquid can be well purified. For this reason, it can use effectively as a raw material of copper plating materials, for example. If zinc or iron is contained in the copper plating material, these impurity metals accumulate in the copper plating bath, which adversely affects the copper plating treatment, and thus the method of the present invention is very advantageous.

And the purification method of this embodiment is a process which makes copper chloride etching waste liquid contact anion exchange resin, and when the adsorption capacity of anion exchange resin falls, it can wash | clean by pure water, for example, and can recover the adsorption capacity. This can simplify the purification of the waste liquid and at low operating cost.

(Example)

The example which performed in order to confirm the effect of this invention is described below. In the test method of each example, an anion (anion) exchange resin was filled in the column as described above to construct an experimental purification column, and the copper chloride etching waste liquid filled in the container was continuously supplied into the column using a pump. It was carried out by sampling and analyzing the liquid discharged from the column for each elapsed time after the start of supplying, that is, the passing time (sampling time).

(First embodiment)

As an anion exchange resin, 100 mL of "DIAION (registered trademark) PA316", a strong base anion exchange resin manufactured by Mitsubishi Chemical Corporation, was charged to the column, and the copper chloride etching waste solution was passed through with SV = 1.5 hr ^-1 . SV stands for Space Velocity. As a composition of the copper chloride etching waste liquid, Cu concentration was 10.2%, free HCl concentration 7.6%, Fe concentration 320 ppm, Zn concentration 40 ppm, and pH was -1.3. In addition, the temperature of the liquid was managed at 60 +/- 2 degreeC. The result of analyzing the liquid discharged | emitted from the column is shown in FIG.

(Second Embodiment)

The copper chloride etching waste liquid had a Cu concentration of 8.6%, a free HCl concentration of 1.5%, a NaCl concentration of 9.3%, a Fe concentration of 5 ppm, and a Zn concentration of 43 ppm, the pH of the liquid was -0.5, and the temperature was controlled at 20 ± 2 ° C. The test was conducted in the same manner as in Example 1 except for the one. The result of analyzing the liquid discharged | emitted from the column is shown in FIG.

(Third Embodiment)

As an anion exchange resin, 50 mL was filled to the column using the same resin as Example 1, and the copper chloride etching waste liquid was passed through with SV = 1hr- ¹ . The copper chloride etching waste liquid had a Cu concentration of 8.1%, a free HCl concentration of 1% or less, a NaCl concentration of 9.2%, a Fe concentration of 48 ppm, and a Zn concentration of 25 ppm, and the pH of the liquid was +1.0. The temperature of the liquid was controlled at 40 ± 2 ° C. The result of analyzing the liquid discharged | emitted from the column is shown in FIG.

(Fourth Embodiment)

As an anion exchange resin, 50 mL of the column was filled with a column of "Unverlite (registered trademark) IRA96SB", a weakly basic anion exchange resin manufactured by Rohm & Haas, and the copper chloride etching waste solution was changed to SV = 1.0 hr ^-1 . It was passed. The composition of the copper chloride liquid was 11.2% of Cu concentration, 8.2% of free HCl concentration, 70 ppm of Fe concentration, and 40 ppm of Zn concentration, and the pH of the liquid was -1.3. The temperature of the liquid was managed at 20, 40, and 50 +/- 2 degreeC. The result of analyzing the liquid discharged | emitted from the column is shown in FIG.

(Fifth Embodiment)

The copper chloride etching waste liquid had a Cu concentration of 8.1%, a free HCl concentration of 1% or less, a NaCl concentration of 9.2%, a Fe concentration of 48 ppm, and a Zn concentration of 25 ppm, the pH of the liquid was +1.0, and the temperature of the liquid was 40 ± 2. The test was carried out similarly to Example 4 except having managed at ° C. The result of analyzing the liquid discharged | emitted from the column is shown in FIG.

(Comparative Example)

A strong acid cation exchange resin (DIAION SKlB manufactured by Mitsubishi Chemical Corporation) was used in place of the anion exchange resin as a resin to be filled in the column. The etching waste liquid was passed through with SV = 1.0 hr- ¹ . As the composition of the copper chloride etching waste liquid, the Cu concentration was 10.1%, the free HCl concentration, 7.6%, the Fe concentration 12 ppm, the Zn concentration 46 ppm, and the pH was -1.3. The temperature of was controlled at 20 ± 2 ℃.

(Test Results and Discussion)

Referring to FIG. 2, which is a result of using the strong basic anion exchange resin according to the first embodiment, the Cu concentration is constant unchanged from the concentration in the original copper chloride etching waste solution regardless of the sampling time, but the sampling time is up to 4 hours, namely Until the elapsed time of the passing liquid is 4 hours, the concentrations of Fe and Zn are 1 ppm or less. Therefore, it can be seen that by using a strong basic anion exchange resin, Cu is hardly adsorbed to the resin and remains in the liquid, while Fe and Zn are adsorbed to the resin and removed. In addition, it is understood that the Zn concentration is high in the data having a sampling time of 8 hours or more, and in this experiment, the resin is broken and the adsorption capacity of Zn is inferior. In this case, therefore, the purification process can be resumed by washing the resin within 4 hours and restoring the adsorption capacity.

3, which is a test result corresponding to the second embodiment, the Cu concentration is unchanged as in the first embodiment, but the Fe concentration is actually zero. In addition, Zn will remain slightly from this experiment only. However, considering other experimental results, the Zn concentration after 16 hours is low compared to the Zn concentration after 8 hours. It is feed.

Referring to Fig. 4, which is a test result corresponding to the third embodiment, the same results as in the first embodiment, and also the test results of the fourth and fifth embodiments using weakly basic anion exchange resins are shown in Figs. Referring to 6, the same results as in the first embodiment are obtained. Therefore, the use of a weakly basic anion exchange resin or a strong basic anion exchange resin supports the purification of copper chloride etching waste liquid.

The inventors of the present invention judge that it is preferable to set the pH to 1.0 or less in order to improve the stability of the treatment when the purification process is actually performed at an industrial level. From this viewpoint, the test is performed by adjusting the pH of the waste liquid to +1. have.

Further, when sodium hydroxide was added to the copper chloride etching waste liquid used in Examples 3 and 5 and the pH was adjusted to 1.5, no precipitate was found, but the precipitate was found to be 2.0. As described above, this precipitate is copper hydroxide, and therefore, in carrying out the present invention, the pH of the waste liquid can be carried out at an arbitrary value of less than 2, for example, 1.5, and preferably 1 or less. .

In addition, when the same test was carried out using a strongly acidic cation exchange resin instead of an anion exchange resin as a resin (comparative example), the concentrations of Fe and Zn were constant without changing to the concentration in the original copper chloride etching waste liquid. Therefore, in the case of using a strongly acidic cation exchange resin, since both Fe and Zn remain in the liquid without being adsorbed to the resin, it is impossible to purify the copper chloride etching waste liquid.

Below, the effect of this invention is demonstrated based on the knowledge of this inventor. Anionic complexes of metals such as zinc, iron, palladium, cadmium, silver, lead, and mercury are removed by contacting the weakly basic anion exchange resin under conditions of 3 to 7, as described in Patent Document 2. It is known to become. On the other hand, although copper, which is an effective metal in copper chloride etching waste liquid, is known to exist as an anionic complex, the present inventors have found that copper anionic complexes in copper chloride etching waste liquid are difficult to adsorb even when contacted with a weakly basic anion exchange resin. Therefore, by contacting the copper chloride etching waste liquid with the weakly basic anion exchange resin, anionic complexes of iron or zinc are preferentially adsorbed and removed from the resin, but copper anionic complexes are relatively difficult to adsorb. can do. Conventional knowledge suggests that the pH of the solution should be 3 or more, but copper ions are precipitated as copper hydroxide when the pH is too high, so it is considered that the relationship between copper ions and the weakly basic anion exchange resin is not considered. . In addition, in the knowledge of Patent Literature 4, copper ions are adsorbed to the anion exchange resin, but since copper chloride etching waste liquid contains most of the copper in the waste liquid from the effluent from the anion exchange resin, copper concentration, hydrochloric acid concentration and the presence of hydrogen peroxide It is assumed that copper is hardly adsorbed to the anion exchange resin depending on the difference between the impurity metals (nickel, chromium and iron, and zinc).

Wherein yeomhwadong etching waste fluid, for example including copper and glass hydrochloric acid of about 8 wt% to about 10% by weight, most agrees ion Cu ion is thought La Cu ^{2 +,} not Cu ^+. For this reason, it is considered that chlorine ions are more numerous than copper ions, and copper anionic complexes are formed. In addition, since copper ions are significantly higher than iron ions or zinc ions, the inventors of the present invention believed that copper anionic complexes preferentially adsorb to the weakly basic anion exchange resin to inhibit the adsorption of iron and zinc anionic complexes. The addition of hydrochloric acid to a solution of cupric chloride forms the formation of a copper anionic complex in the literature (New Edition Inorganic Chem.

However, although the reason is not clear, it was clear that copper ions are hardly adsorbed to the weakly basic anion exchange resin, as apparent from the experimental examples described below. In addition, this is the same result even if a strong base anion exchange resin is used, not limited to a weak base anion exchange resin as understood from experiment. Therefore, by adjusting the copper chloride etching waste liquid to a pH of, for example, 1.5 or less, without leaving precipitation of copper hydroxide, and contacting these exchange resins, the effective copper ions can remove impurities metal while remaining in the liquid, This makes it possible to purify copper chloride etch waste liquids simply and at low operating costs.

Claims (4)

In the method for obtaining a copper chloride solution by purifying the copper chloride etching waste solution after etching the copper material with an etching solution added hydrochloric acid to the cupric chloride solution, The etching waste liquid is contacted with a weakly basic anion exchange resin or a strong basic anion exchange resin in a pH region where a solid component as a copper hydroxide is not produced, thereby adsorbing and removing the impurity metal to the resin to obtain a purified copper chloride solution. Copper chloride etching waste liquid purification method. The method of claim 1, wherein the pH range is 1.5 or less. The method for purifying copper chloride etching waste liquid according to claim 1, wherein the impurity metals are iron and zinc. The copper chloride etching waste liquid after etching the copper material with the etching liquid which hydrochloric acid was added to the cupric chloride solution was obtained by refine | purifying by the method in any one of Claims 1-3, The refined copper chloride solution characterized by the above-mentioned. .

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