KR19980040479A - Copper waste treatment method - Google Patents

Abstract

The present invention relates to a method of recovering copper in the form of a compound by simultaneously treating ammonia copper waste liquid and hydrochloric acid copper waste liquid by an organic solvent extraction method, recovering copper, and reprocessing the remaining corrosion waste liquid again to an etching solution. Through the process, not only can the high purity copper compound be recovered, but also the nicking liquid can be recovered and used.

Description

Copper waste treatment method

1 is a view showing a continuous extraction process of copper waste liquid according to an embodiment of the present invention.

The present invention recovers high-purity copper from copper waste liquid produced by the production of various printed circuit boards, which are essential parts of electronic products, and recovers the waste liquid after the recovery of copper with corrosion liquid (hereinafter referred to as etching solution). It is about. More specifically, the ammonia copper waste liquid and the hydrochloric acid copper waste liquid generated in the etching process of the printed circuit board are simultaneously treated with an organic solvent extraction method to recover copper of high purity, and after the copper is recovered, the remaining waste liquid is retreated to an etching solution. It relates to a method of regeneration.

In general, a printed circuit board is laminated with a thin copper plate on a plastic plate, and only a desired portion is printed and coated with an etching-resistant ink on the copper plate to protect it from the etching solution, and then the circuit board is brought into contact with the etching solution. The copper of the non-corrosive portion is removed by corrosion, and the anti-corrosive ink is printed and coated so that the non-corrosive portion forms a circuit. Printed circuit boards are classified into single layer and multilayer printed circuit boards. In manufacturing single layer printed circuit boards, only hydrochloric acid copper waste liquid is generated. However, in the manufacture of multilayer printed circuit boards, which are commonly used, hydrochloric acid copper waste liquids are generated when forming inner layer circuits, and ammonia copper waste liquids are generated when outer layer circuits are formed, so the same amount of hydrochloric acid is used in general printed circuit board manufacturing processes. Copper waste liquid and ammonia copper waste liquid will be generated.

Etching liquid is gradually disposed of as copper waste liquid because the copper concentration contained is gradually increased as the service life is increased and the corrosion effect is sharply reduced when the copper concentration is more than 130g / l.

Copper waste liquid is divided into hydrochloric acid copper waste liquid generated by dissolving copper plate using hydrochloric acid and ammonia copper waste liquid produced when dissolving copper plate using ammonia water. Pollutants containing hydrochloric acid or ammonia water, together with copper, cause severe pollution and waste of resources if not treated properly. Therefore, copper is recovered from this copper waste liquid and the treatment waste liquid is recovered by etching or for other uses. Need development

[Objective of the invention]

It is an object of the present invention to economically process copper hydrochloric acid copper waste liquid and ammonia copper waste liquid through a simple process to recover copper, and also to recover the treated waste liquid back into etching liquid.

[Technical Field to which the Invention belongs and Conventional Technology in the Field]

Conventional treatment of copper waste liquid is performed by recovering copper from hydrochloric acid copper waste liquid, recovering copper from ammonia copper waste liquid, or from ammonia and hydrochloric acid copper waste liquid using techniques such as electrolytic method, organic solvent extraction method, ion exchange membrane electrolytic method, etc. There is a known method for recovering, but all of these treatments have great problems in terms of process and economics.

In other words, Japanese Patent Laid-Open Publication No. 55-145176 and Japanese Patent Application Laid-Open No. 55-145177 disclose a method of recovering copper of corrosion waste liquid using an electrolytic cell, but these methods have a large amount of corrosion of the apparatus and excessive investment in facilities. There is a problem that the processing is difficult.

In addition, although Japanese Patent Application Publication Nos. 62-53592 and 54-146233 disclose organic solvent extraction methods, these methods are capable of treating only ammoniacal copper waste liquids, and generally hydrochloric acid copper waste liquids generated in the same amount during the manufacturing process. There is a crucial problem that cannot be handled.

In addition, Japanese Patent Application Laid-Open No. 61-246395, Japanese Patent Application No. 61-133192, and the like are used as ion exchange membrane electrolytic methods, but these methods are expensive in terms of cost and excessive investment in facilities.

There is a conventional method of recovering copper from the ammonia-based copper waste liquid by adding caustic soda to the ammonia copper waste liquid, heating it to precipitate copper oxide, recovering it, and volatilizing and collecting ammonia. The product value is low because it contains impurities, and it is necessary to dissolve the acid again when converting it to copper sulfate or copper chloride, and it is uneconomical because it requires an additional process of reprocessing the waste liquid after recovery of copper oxide. In addition, the method disclosed in Korean Patent Publication No. 94-7179 for extracting copper with an organic solvent and regenerating etching solution with respect to the ammonia-based copper waste liquid has a problem in that the hydrochloric acid copper waste liquid cannot be treated.

There is a conventional method for recovering copper from copper acid hydrochloric acid, which is obtained by adding iron or zinc to copper acid hydrochloric acid, to obtain copper, and dissolving iron chloride or zinc chloride. It is contained, there is a problem that must be re-smelted. In addition, the method disclosed in Japanese Patent Publication No. 60-116789, which recovers electrolytic copper by electrolysis of hydrochloric acid copper waste liquid, can recover copper of relatively high purity, but there is a risk of corrosion of the device due to by-produced hydrochloric acid and difficulty in operation. There is this.

A method for recovering copper by mixing ammonia copper waste liquid and hydrochloric acid copper waste liquid is to obtain basic copper chloride as a precipitate by neutralizing the hydrochloric acid copper waste liquid in a pH 3-6 range with ammonia copper waste liquid. There is a method disclosed in. However, the method disclosed in Korean Patent Publication No. 93-4476 is low in purity because of the simultaneous precipitation of ammonium chloride, a reaction by-product, in addition to basic copper chloride, it is difficult to control the particle size when filtering the precipitate, and is added when converting to a copper product. There is a problem that a process is required.

[Technical Challenges to Invent]

The present invention has been made to solve the problems of the prior art, including the complicated process, the economical and hydrochloric acid copper and ammonia copper is difficult to simultaneously process, low purity and the like.

Composition and Action of the Invention

The present inventors have studied to solve the above various problems, and when the mixture of acidic copper acid hydrochloric acid and ammonia copper waste liquid is adjusted to pH 2 or less to prepare a mixed waste liquid without precipitation of reaction by-products or basic copper chloride, Invented a new technology that extracts copper with an organic solvent containing a liquid catalyst to recover high-purity copper in a compound state, and at the same time, adds a small amount of additives to the extraction waste liquid after recovering copper, and regenerates it entirely with an etching solution. . Hereinafter, the configuration and operation of the present invention will be described in detail.

The present invention comprises the steps of neutralizing the acidic copper waste liquid and the ammonia copper waste liquid to pH 2 or less, and contacting the mixed copper waste liquid with an organic solvent containing a liquid catalyst to extract the copper ions to the organic solvent phase And it provides a method for recovering high purity copper from the copper waste liquid comprising the step of recovering the extracted organic solvent phase with an inorganic acid to recover a high purity copper in a compound state.

In general, the composition of ammonia copper waste liquid and hydrochloric acid copper waste liquid discarded due to the increase of copper concentration is shown in Table 1 below.

division Total Cu content Ammonium Chloride (NH ₄ Cl) Hydrochloric acid (HCl) Ammonia (NH ₃ ) Ammonia Copper Waste 100-170 240 to 300 80-120 - Acid hydrochloric acid copper waste liquid 110 to 150 - 70-100

(Unit; g / l)

The present invention mixes ammonia-based copper waste solution with hydrochloric acid copper waste solution and neutralizes it to pH 2 or less, and then contacts with an oxime-based, diketone-based, phosphoric-acid-based, carboxylic-based or phosphinic-based organic solvent containing a liquid catalyst. A method of extracting ions into an organic solvent phase was used, wherein the mixed waste solution to pH 2.5 or less, and more preferably to pH 1.5 to 2.0, is a mixture of ammonia copper waste acid and hydrochloric acid copper waste liquid as shown in Formula 1 below. If the mixed solution has a pH of 3 or more, ammonium chloride and basic copper chloride, which are reaction byproducts, are precipitated, so it is difficult to extract copper. Thus, it is preferable to prepare a clear mixed waste liquid without precipitation of the reaction byproduct or basic copper chloride and extract copper by adjusting the pH. Because. The reason why the organic solvent extraction process is adopted is that it is possible to economically recover high purity copper of 99% or more.

[Formula 1]

Cu (NH ₃ ) ₄ Cl ₂ + 4H ₂ O + ₂ CuCl ₂ → CuCl ₂ 2Cu (CH) ₂ + ₄ NH ₄ Cl

When the pH of the mixed copper waste liquid is 2.5 or less, the rate of extracting copper ions from the copper waste liquid into the organic solvent phase is significantly lowered, thereby increasing the size of the extraction device. However, the present invention solves such problems by introducing a liquid catalyst into the organic solvent. . This will be described in detail as follows.

When the ammonia copper waste liquid, hydrochloric acid copper waste liquid, and the acidic solution mixed waste liquid are contacted with an organic solvent, an extraction reaction occurs simultaneously in the ammonia copper waste liquid and the hydrochloric acid copper waste liquid, and the typical reactions are represented by Chemical Formulas 2 and 3.

[Formula 2]

Extraction of Copper from Ammonia Copper Waste

Cu (NH ₃ ) ₄ Cl ₂ + 2RH → CuR ₂ + 2NH ₄ Cl + 2NH ₃

[Formula 3]

Extraction reaction of copper from acidic hydrochloric acid

CuCl ₂ + 2RH → CuR ₂ + 2HCl

In the above scheme, R represents an organic solvent.

In this extraction reaction, ammonia (NH ₃ ) is a by-product from ammonia copper waste solution and hydrochloric acid (HCl) is a by-product from hydrochloric acid copper waste solution.Ammonia and hydrochloric acid are neutralized to stabilize the pH of mixed aqueous solution. Since the reaction proceeds in, it is easy to extract the copper. In the case where the same amount of ammonia copper waste liquid and hydrochloric acid copper waste liquid are mixed, the pH becomes 3 or more. As the inorganic acid, sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, and the like are preferable, and sulfuric acid and hydrochloric acid are more preferable.

Organic solvents that can be used for the purpose of extracting copper in the present invention are oxime, diketone, phosphoric acid, carboxylic acid, phosphinic acid and the like, and specifically include the following compounds.

Oxime system: 5,8-Diethyl-7hydroxy-6-dodecanone oxime

2-hydroxy-5 dodecyl benzophenone oxime

2-hydroxy-5 nonyl benzo oxime

2-hydroxy-5 nonyl acetophenone oxime

2-hydroxy-3 chloro-5-nonyl benzo oxime

5-nonyl saricil oxime

Diketone series: phenylalkyl beta-diketone

Phosphoric acid system: di-2-ethylhexyl phosphate (D2EPHA)

2-ethylnucleosilhydrogen 2-ethylhexyl phosphoric acid (PC 88A)

Carboxylic acid type: Versatic acid

Phosphonic acid: Cyanex 301, 302, 303

An oxime system is preferable among the above organic solvents, and, as a brand name, LIX 84, LIX 54, etc. made by Henkel Corporation are preferable. In addition, the above organic solvents may be used alone or in combination of two or more. The composition of the organic solvent for copper extraction may be generally composed of 5-90% of the organic solvent, 10-95% of a diluent such as petroleum, but when extracting copper from a high concentration of copper waste liquid, the total volume of the organic solvent for copper extraction When it is 100% it is preferable to use an oxime organic solvent of 30% by volume.

When the pH of the mixed copper liquid is 2.5 or less, the extraction rate of copper ions into the organic solvent phase of the copper waste liquid is significantly lowered, so that the extraction apparatus is enlarged. However, in the present invention, the extraction solvent is used as an organic solvent of copper ions in the copper solvent. This problem has been solved uniquely by introducing a liquid catalyst which significantly increases the extraction speed and speeds up the separation of the extraction solvent and the copper waste solution.

The liquid catalysts used are paraffinic, aromatic and naphthenic hydrocarbon compounds having a boiling point in the range of 100-250 ° C. and mixtures thereof, for example isodecanol, 2-ethylhexanol, thiributyl phosphate (TBP), nonyl Alcohols or mixtures thereof, preferably isodecanol, 2-ethylhexanol, or commercially available organic solvent mixtures such as cocosol, etc. are suitable. In the present invention, the liquid catalyst is preferably 5-70% by volume, more preferably 20-50% by volume, when the total volume of the organic solvent for copper extraction is 100%.

Copper, which has been transferred to the organic solvent phase according to the above extraction process, is back extracted with an inorganic acid solution such as sulfuric acid, hydrochloric acid and nitric acid. For example, when back-extracted with an aqueous sulfuric acid solution, the reaction is as shown in Chemical Formula 4.

[Formula 4]

CuR ₂ + H ₂ SO ₄ → 2RH + CuSO ₄

The inorganic acid solution used for back extraction (hereinafter referred to as back extraction) is reused until a certain concentration of copper is concentrated. In this back extract, the activated carbon layer may be passed to remove the contamination of the organic solvent. The back extract containing high concentration of copper can add a small amount of concentrated acid to precipitate saturated mineral acid salts, or evaporate and concentrate to recover the inorganic acid salts in crystalline state. The method of throwing in and recovering is preferable. In addition, the remaining liquid after copper extraction was ammonia water (NH ₃ solution), ammonium carbonate (NH ₄ HCO ₃ ), ammonium phosphate ((NH ₄ ) ₃ (PO ₄ )), ammonium nitrate (NH ₄ NO ₃ ), sodium salt (NaClO _A small amount of stabilizer and corrosion inhibitor as in ₂ ) can be added and recycled into the etchant.

Hereinafter, an embodiment of the present invention has been disclosed. However, the scope of the present invention is not limited by the following examples.

Example 1

The composition of hydrochloric acid copper waste liquid and ammonia copper waste liquid used in the experiment is shown in Table 2.

division Total Cu content Ammonium Chloride (NH ₄ Cl) Hydrochloric acid (HCl) Ammonia (NH ₃ ) Ammonia Copper Waste 130 240 89 - Acid hydrochloric acid copper waste liquid 115 - - 76

(Unit: g / l)

100 ml of ammonia-based copper waste solution was mixed with 100 ml of hydrochloric acid hydrochloric acid solution, and then, 95 ml of distilled water and 5 ml of sulfuric acid were added to prevent precipitation of ammonium chloride into crystals while adjusting the pH to 2.0. . The organic solvent was prepared by mixing 30% oxime (LIX 84), 30% cocosol (trade name), and 40% petroleum by volume ratio. 300 ml of the prepared organic solvent and 300 ml of mixed copper liquid are placed in a 1-liter funnel, shaken vigorously for 2 minutes, and left for 5 minutes to separate the aqueous phase and the organic solvent phase. The aqueous phase is separated with a separatory funnel, and 300 ml of distilled water is added to the remaining organic solvent, followed by vigorous shaking to separate the washing solution from the organic solvent. 300ml of 30% sulfuric acid solution was added to the washed organic solvent, and vigorously shaken for 2 minutes, copper ions were back extracted into sulfuric acid solution. The organic solvent extracted back is strongly acidic, so the remaining acid groups are washed twice with distilled water, the first aqueous phase is adjusted to pH 2 by adding ammonia water, and extracted again with organic solvent. At this time, the sulfuric acid solution is repeatedly used, and the six-extracted aqueous phase is changed from dark green to colorless and clear solution, and the copper ion concentration is 3 ppm or less. The back extracted sulfuric acid solution was evaporated and concentrated to obtain 24g of crystals of copper sulfate, and the purity of copper sulfate was 99.9% or more based on CuSO ₄ · 5H ₂ O, and the concentrations of impurities are shown in Table 3 below.

Cu Fe Zn Ni CD As Ca Sn Na 25.61% 2 ppm 3 ppm a very small amount a very small amount 0.15 ppm a very small amount a very small amount a very small amount

Only 172 g / l of ammonium chloride remained in the 300 ml extract, which was extracted with copper, and 75 ml of ammonia water, 10 g of ammonium carbonate, 100 mg of sodium salt, 30 mg of ammonium nitrate, and 0.3 mg of ammonium phosphate were added to the etching solution.

Example 2

Copper was extracted in the same manner as in Example 1 and high purity (99.9%) of copper nitrate was obtained using a 30% nitric acid solution as a back extract.

Example 3

Copper was extracted in the same manner as in Example 1, and high-purity (99.9%) copper chloride was obtained using a 25% aqueous hydrochloric acid solution as a back extract.

Example 4

Example 1 was applied to a continuous process, and the same copper mixture and the organic solvent as in Example 1 were contacted and separated with a countercurrent mixer-settler apparatus, and 30% aqueous sulfuric acid solution was used as the back extraction inorganic acid. At this time, the ratio of the organic solvent phase and the aqueous phase was tested to be 8: 1, and the extraction stage was 4 stages, the washing stage 2 stages, the back extraction stage 2 stages, and the back extraction after the extraction stage 2 stages. Ammonia water was added from each extraction stage to maintain a pH of 2, and the residence time was 2 minutes in the mixer and 8 minutes in the settler. In this process, the concentration of copper ions discharged into the aqueous phase was 3 ppm or less, and the copper purity was 99.9% or more based on the copper sulfate product standard. This process is shown in FIG.

[Effects of the Invention]

By treating hydrochloric acid copper waste liquid and ammonia copper waste liquid generated in the process of manufacturing a printed circuit board by the method of the present invention at the same time, it is possible to recover and recycle the copper compound of high purity as well as to regenerate and use the corrosion liquid. Printed circuit board manufacturers can solve various problems associated with copper waste treatment because industrial waste does not occur. The recovered copper is widely used industrially in addition to high-purity copper sulfate, which is used as copper plating, pigment, mordant, and leather treatment agent. There is an economic advantage to recover with copper chloride or copper nitrate.

Claims (13)

Mixing the acidic copper waste fluid and the ammonia copper waste liquid and adjusting the acidity to pH 2.5 or less, and contacting the mixed copper waste liquid adjusted to pH 2 or less with an organic solvent containing a liquid catalyst to form copper ions in an organic solvent phase. And extracting copper ions from the extracted organic solvent and recovering copper in a compound state. The method of claim 1, wherein the acidity of the mixed copper waste liquid is adjusted to a pH range of 1.5 to 2.0. The method of claim 1, wherein the organic solvent is selected from the group consisting of oxime, diketone, phosphoric acid, carboxylic acid, phosphinic acid and mixtures thereof. The oxime organic solvent according to claim 3, wherein the oxime organic solvent is 5,8-dimethyl-7hydroxy-6-dodecanone oxime, 2-hydroxy-5 dodecyl benzophenone oxime, 2-hydroxy-5 nonyl benzo oxime , 2-hydroxy-5 nonyl acetophenone oxime, 2-hydroxy-3 chloro-5-nonyl benzo oxime, 5-nonyl saricil oxime, and a mixture thereof. Treatment method. The method of claim 3, wherein the diketone organic solvent is phenylalkyl beta-diketone. The method of claim 3, wherein the phosphate organic solvent is selected from the group consisting of di-2-ethylhexyl phosphate (D2EPHA), 2-ethylhexylhydrogen 2-ethylhexyl phosphate (PC 88A), and mixtures thereof. Copper waste liquid treatment method characterized in that. The method of claim 3, wherein the carboxylic acid-based organic solvent is versatic acid. The method of claim 3, wherein the phosphinic acid-based organic solvent is selected from the group consisting of Cyanex (301), 302, 303 or more. [Claim 3] The method of claim 2, wherein the liquid catalyst is selected from among paraffinic, aromatic, naphthenic hydrocarbon compounds and mixtures thereof having a boiling point of 100 to 250 ° C. 10. The method of claim 9, wherein the liquid catalyst is selected from the group consisting of isodecanol, 2-ethylhexanol, thiributyl phosphate (TBP), nonyl alcohol and mixtures thereof. The method for treating copper waste liquid according to claim 1, wherein the reverse extraction is performed by adding an inorganic acid. 12. The method of claim 11, wherein the inorganic acid is selected from sulfuric acid, nitric acid, hydrochloric acid. And a salt is added to the residual waste liquid from which the copper is extracted from the organic solvent extraction step and the reverse extraction step to prepare a regenerated etching solution.