KR101030080B1 - Method for preparing copper chloridei from waste copper liquid and system thereof - Google Patents

Abstract

The present invention relates to a method and a system capable of producing a large amount of high purity copper chloride at low cost. The method for preparing copper chloride from the copper waste liquid of the present invention comprises the steps of reacting the copper waste liquid with hydrochloric acid, and a reducing agent; Filtering the reaction solution to remove the filtered insoluble matter; Concentrating the filtrate filtered in the filtration step; Cooling the concentrated solution concentrated in the concentration step; Dewatering the cooled product cooled in the cooling step; Washing the dehydrated dehydrated in the dehydration step; And drying the washings washed in the washing step to obtain cuprous chloride. The system for producing copper chloride from the copper waste liquid of the present invention comprises: a reaction tank (10) in which copper waste liquid, hydrochloric acid, and a reducing agent are administered to react; A filter 20 for filtering insoluble materials after completion of the reaction in the reactor 10; A concentration tank 30 for concentrating the filtrate filtered through the filter 20; A cooling tank 40 for cooling the concentrated liquid concentrated in the concentration tank 30; Dehydration tank (50) for dehydrating and washing the crystallized crystallization in the cooling tank (40); And a dryer 60 for drying the dewatered cake dehydrated in the dehydration tank 50.

Copper chloride, copper waste liquid, etching waste liquid, hydrochloric acid

Description

METHOD FOR PREPARING COPPER CHLORIDE (I) FROM WASTE COPPER LIQUID AND SYSTEM THEREOF

The present invention relates to a method and a system for preparing copper chloride from copper waste liquid, and more particularly, to reduce the copper chloride shift contained in copper waste liquid to copper chloride, which is filtered, concentrated, and crystallized to obtain high purity. A method and system for producing copper at low cost in large quantities.

As demand for electronic products increases, so does the demand for printed circuit boards (PCBs). In the process of etching the copper film disposed on the PCB surface, a large amount of waste liquid containing copper is generated, and the amount of copper contained in the waste liquid is about 10 to 15%. The recovery of copper from wastewater from the PCB industry is important in terms of recycling raw materials and preventing environmental pollution.

Conventionally, there is a method of preparing cuprous chloride from copper waste liquid by adding HCl or NaCl to the etching waste liquid and reacting with metallic copper to precipitate cuprous chloride in a large amount of water. However, this method has a problem in that the production yield of cuprous chloride is low at 80 to 87%, the cupric chloride is low in purity, and the capacity of the manufacturing equipment is large.

In addition, Japanese Laid-Open Patent Publication No. 7-25613 discloses a crystal separation method based on a temperature difference after reduction reaction by concentrating an etching waste liquid to a certain concentration and then adding a reducing agent. This method can obtain relatively high purity copper chloride, but a large amount of waste hydrochloric acid is generated and the yield of copper chloride is low.

Accordingly, the inventors of the present invention devised the present invention by developing a method and a system capable of producing a large amount of high purity copper chloride from copper waste liquid at low cost.

It is an object of the present invention to provide a method for producing a high-purity cuprous chloride at low cost by reducing chlorinated copper chloride contained in copper waste liquid to copper chloride.

It is another object of the present invention to provide a system for producing a high-purity cuprous chloride at low cost by reducing chlorinated copper chloride contained in copper waste liquid to copper chloride.

Another object of the present invention is to reduce the cost of the final waste water treatment by recovering almost all of the copper contained in the copper waste liquid.

The method for producing cuprous chloride from the copper waste liquid of the present invention,

Reacting the copper waste solution with hydrochloric acid and a reducing agent;

Filtering the reaction solution to remove the filtered insoluble matter;

Concentrating the filtrate filtered in the filtration step;

Cooling the concentrated solution concentrated in the concentration step;

Dewatering the cooled product cooled in the cooling step;

Washing the dehydrated dehydrated in the dehydration step; And

Drying the washings washed in the washing step to obtain cuprous chloride; characterized in that comprises a.

The system for producing cuprous chloride from the copper waste liquid of the present invention,

A reaction tank 10 in which copper waste solution, hydrochloric acid, and a reducing agent are administered to react;

A filter 20 for filtering insoluble materials after completion of the reaction in the reactor 10;

A concentration tank 30 for concentrating the filtrate filtered through the filter 20;

A cooling tank 40 for cooling the concentrated liquid concentrated in the concentration tank 30;

Dehydration tank (50) for dehydrating and washing the crystallized crystallization in the cooling tank (40); And

It characterized in that it comprises a; dryer (60) for drying the dehydration cake dehydrated in the dehydration tank (50).

The method for producing cuprous chloride from the copper waste liquid of the present invention can not only produce a large amount of high purity copper cup copper at a low cost, but also the process is simple and can easily prepare cuprous chloride from the copper waste liquid.

In addition, cuprous chloride recovered by the method of the present invention is a crystalline powder, the drying operation is easy.

In addition, by using the method of the present invention, the copper contained in the copper waste liquid is almost recovered, thereby reducing the cost of wastewater treatment.

The method for producing cuprous chloride from the copper waste liquid of the present invention,

Reacting the copper waste solution with hydrochloric acid and a reducing agent;

Filtering the reaction solution to remove the filtered insoluble matter;

Concentrating the filtrate filtered in the filtration step;

Cooling the concentrated solution concentrated in the concentration step;

Dewatering the cooled product cooled in the cooling step;

Washing the dehydrated dehydrated in the dehydration step; And

Drying the washings washed in the washing step to obtain cuprous chloride; characterized in that comprises a.

Hereinafter, the method for producing cuprous chloride from the copper waste liquid of the present invention will be described in detail.

1 is a flowchart schematically showing a process of preparing cuprous chloride of the present invention.

First, copper waste liquid, hydrochloric acid, and a reducing agent are reacted.

The copper waste liquid used in the present invention may be any liquid containing copper, and is not limited to a specific copper waste liquid. Moreover, the copper content contained in copper waste liquid is not limited. However, copper waste liquids which are preferably used are etching waste liquids containing a large amount of copper generated during the corrosion process in PCB manufacturing. In addition, a copper waste liquid containing 5 to 20% of copper is preferably used. That is, in the method for producing cuprous chloride of the present invention, cuprous chloride of high yield can be recovered even by using a copper waste liquid having a low copper content.

The hydrochloric acid concentration in the reaction step in the method of the present invention is preferably 10 to 35%.

As the reducing agent in the method of the present invention, any substance which reduces Cu ⁺² contained in copper waste liquid to Cu ⁺ can be used.

At least one reducing agent preferably used in the present invention is selected from the group consisting of copper, iron, zinc and hydrazine. Copper used in the present invention is preferably used having a copper content of 30 to 99%. Particularly, in the method of the present invention, copper powder containing a large amount of impurities such as iron can be used as the reducing agent, but copper powder containing 3% or more of iron and 7% of iron can be used.

When the copper waste solution, hydrochloric acid and the reducing agent in the method of the present invention is preferably reacted at 70 to 110 ℃. If the reaction is less than 70 ℃ there is a problem that the reduction efficiency is reduced, if the reaction at a temperature above 110 ℃ there is a large heat loss problem. Preferable reaction temperature is 90-100 degreeC.

The reaction scheme formed in the reaction step of the present invention is as follows:

CuCl ₂ + Cu + xHCl → 2CuCl + xHCl (if copper is used as reducing agent)

CuCl ₂ + NH ₂ NH ₂ H ₂ O → CuCl + NH ₄ Cl + NH ₃ (if hydrazine is used as the reducing agent)

Once the reaction is complete, the filtered insolubles are removed. Copper (Cu ⁺ ) reduced from Cu ⁺² to Cu ⁺ by the reducing agent is present in the filtrate.

Then, the filtrate is concentrated. Concentration is intended to precrystallize the copper chloride produced by making the filtrate supersaturated. Concentration is preferably performed in a vacuum state. Concentration is preferably carried out at 70 to 90 ℃, concentration below 70 ℃ has a problem of low concentration efficiency, there is a problem that is not economical without the effect of increasing the concentration at a temperature above 90 ℃. At this time, the concentration is preferably concentrated until the concentration of about 30 to 60% remain. If the concentrate is concentrated until it remains less than 30%, it takes a long time and there is a problem in that the transfer amount is difficult to increase, and if the concentrate is concentrated beyond 60%, there is a problem that the early crystallization efficiency is lowered.

The concentrate is then cooled. Copper chloride crystallizes by cooling. It is preferable to perform cooling at 60 degrees C or less. The cooling may be performed at room temperature or may be cooled using a cooler for rapid crystallization.

The coolant is then dewatered.

Then, the dehydrated product is washed. At this time, when washing the dehydrated with water it is preferable to wash by administering an antioxidant to the water. This serves to prevent copper chloride from being oxidized. Antioxidants which are preferably used in the present invention are phosphoric acid or phosphate salts (e.g., sodium hypophosphate, etc.). In the method of the present invention, the amount of antioxidant is preferably used 0.01 to 1% relative to the final amount of the amount of chloride.

In the method for producing cuprous chloride of the present invention, the water from which the dehydrated product is washed is treated with wastewater.

Then, the washed washings are dried to obtain cuprous chloride.

The cuprous chloride obtained by the method of the present invention is a powder that is obtained as a crystalline powder does not agglomerate easily and is easy to dry. Drying may be carried out using a natural drying or a commonly used dryer. It is preferable to perform drying in a vacuum state. In the case of using a dryer, a stirred vacuum dryer, a mixer vacuum dryer or a hot air dryer (under nitrogen or under an inert gas) is preferably used.

In the method of producing cuprous chloride of the present invention, condensed and recovered waste hydrochloric acid distilled in the concentration step is characterized in that it is administered in the reaction step. The reuse of waste hydrochloric acid can reduce the amount of hydrochloric acid used in the reaction step.

The amount of waste hydrochloric acid returned in the method for producing cuprous chloride of the present invention is preferably 30 to 60% by weight of the total amount of waste hydrochloric acid. When the amount of waste hydrochloric acid returned is 30 to 60% by weight, the amount of hydrochloric acid newly administered in the reaction step can be minimized. If the amount of waste hydrochloric acid returned exceeds 60% by weight, the reaction efficiency is lowered by diluting the concentration of hydrochloric acid newly administered.

In addition, in the method for producing cuprous chloride according to the present invention, the dehydration liquid dehydrated in the dehydration step is characterized in that it is administered in the reaction step. This is to increase the recovery rate of copper remaining in the dehydration amount. In addition, as the dewatering liquid is re-administered in the reaction step, the wastewater is easily treated because the content of copper is low in the final wastewater, and the wastewater treatment cost is reduced.

Next, a system for producing cuprous chloride from the copper waste liquid of the present invention will be described. In the description of the system for producing cuprous chloride from the copper waste liquid of the present invention, portions overlapping with the method for producing cuprous copper chloride from the copper waste liquid described above will be omitted.

The system for producing cuprous chloride from the copper waste liquid of the present invention,

A reaction tank 10 in which copper waste solution, hydrochloric acid, and a reducing agent are administered to react;

A filter 20 for filtering insoluble materials after completion of the reaction in the reactor 10;

A concentration tank 30 for concentrating the filtrate filtered through the filter 20;

A cooling tank 40 for cooling the concentrated liquid concentrated in the concentration tank 30;

Dehydration tank (50) for dehydrating and washing the crystallized crystallization in the cooling tank (40); And

It characterized in that it comprises a; dryer (60) for drying the dehydration cake dehydrated in the dehydration tank (50).

An example of a system for producing cuprous chloride of the present invention is shown in FIG. 2, and the system of the present invention will be described in detail with reference to FIG.

In the system for producing cuprous chloride from the copper waste liquid of the present invention, a reaction tank 10 is provided in which copper waste liquid, hydrochloric acid and a reducing agent are administered to react. Copper waste, hydrochloric acid and reducing agents may be administered directly to the reactor, each individual tank is provided may be controlled by a valve in each tank to be administered to the reactor.

The reactor 10 is connected to the filter 20 by the usual connection means. After the reaction is completed in the reactor 10, the reactant is moved to the filter 20 through the connecting means to filter the insoluble matter in the filter.

The filter 20 is connected to the concentration tank 30 by conventional connecting means. The filtrate filtered by the filter 20 is transferred to the concentration tank 30 through the connecting means and is concentrated.

The concentration tank 30 is connected to the cooling tank 40 by the usual connection means. The concentrated liquid concentrated in the concentration tank 30 is moved to the cooling tank 40 through the connecting means, and the concentrated liquid is cooled in the cooling tank 40.

The cooling tank 40 is connected to the dehydration tank 50 by the usual connection means. The crystallized crystallized by cooling in the cooling tank 40 is moved to the dehydration tank 50 through the connecting means and dehydrated and washed in the dehydration tank 50.

The dehydration tank 50 is connected to the dryer 60 by the usual connection means. Solids dehydrated in the dehydration tank 50 are transferred to the dryer 60 through the connecting means and dried in the dryer 60 to obtain crystalline powder.

In the cuprous chloride production system of the present invention, a condenser 34 for condensing the vapor distilled upon concentration in the concentration tank 30 is provided, and the condenser 34 is connected to the concentration tank 30. In the cuprous chloride production system of the present invention, a plurality of condensers for condensing hydrochloric acid distilled in the concentration tank 30 may be provided.

In the cupric chloride production system of the present invention, a waste hydrochloric acid recovery tank (70) for recovering waste hydrochloric acid distilled in the concentration tank (30) and condensed through a condenser is provided, and the hydrochloric acid in the waste hydrochloric acid recovery tank (70) is provided. It is characterized in that it further comprises a waste hydrochloric acid return line 72 to be returned to the reaction tank (10). Waste hydrochloric acid, which is sent to the reaction tank 10 through the waste hydrochloric acid return line 72, may be reused to reduce the amount of hydrochloric acid newly administered in the reaction step.

The cuprous chloride production system of the present invention is characterized in that it further comprises a dehydration liquid feed line 52 for returning the filtrate dehydrated in the dehydration tank 50 to the reaction tank (10). The dehydrated water sent to the reaction tank 10 through the dehydration liquid return line 52 is reused in the reaction step. This is to increase the recovery rate of copper remaining in the dehydration amount.

In the copper chloride production system of the present invention, the heat exchanger 36 is installed outside the concentration tank 30, and the liquid in the concentration tank 30 is transferred to the heat exchanger by a pump (not shown) installed outside the concentration tank 30. 36) and is conveyed back to the concentration tank (30). That is, the liquid in the concentration tank 30 is circulated while passing through the heat exchanger by the pump.

Heat exchanger preferably used in the present invention is an inner tube type, by using a heat exchanger to supply heat in a short time, the concentration temperature rises quickly and the concentration time is shortened.

In the cuprous chloride production system of the present invention, a stirrer (not shown) may be installed in the reaction tank, the concentration tank, and the dryer.

In the copper chloride production system of the present invention, conventional connecting means (eg, pipes) for connecting a reaction tank, a filter, a concentration tank, a cooling tank, a dehydration tank, a dryer, and the like are used in the art. It is possible to control the flow of fluid transfer valves and pumps, etc. shall not be described separately.

Hereinafter, a method and a system for preparing copper chloride from the copper waste liquid of the present invention will be described in more detail with reference to the following Examples and Comparative Examples.

≪ Example 1 >

2000 g of etching waste solution (Cu 10% by weight), 500 g of hydrochloric acid (35%) and 260 g of copper powder (3.5% by weight of Fe, 80% by weight of Cu) were administered to the reactor, reacted at 90 to 98 ° C for 1 hour, and then transferred to the filter press. Filtered to separate the insolubles. The filtrate was transferred to a concentration tank and concentrated in vacuo at 80 to 90 ° C. until the filtrate was 50%. The concentrate was transferred to a cooling bath and cooled to room temperature. The coolant was transferred to a dehydration tank for dehydration, and 0.3 g of phosphoric acid was added to 1000 g of water, followed by washing of the dehydrated product. The washed solid was put into a mixer-type vacuum dryer and dried to obtain 310 g of crystalline powder, and 1000 g of a dehydration filtrate (20 wt% of copper concentration). According to the KS standard quantitative analysis, the content of cuprous chloride in crystalline powder was 99.8%.

<Example 2>

Etching waste solution (Cu 10% by weight) 1000g, hydrochloric acid (35%) 250g, copper powder (Fe 3.5% by weight, Cu 80% by weight) 130g, waste hydrochloric acid solution (distilled and condensed when concentrated in Example 1) and dehydration solution (In the case of dehydration in Example 1) 1000g was administered to the reaction tank and reacted for 1 hour at 90 to 98 ℃ and then transferred to the filter press and filtered to separate the insoluble matters. The filtrate was transferred to a concentration tank and concentrated in vacuo at 80 to 90 ° C. until the filtrate was 50%. The concentrate was transferred to a cooling bath and cooled to room temperature. The coolant was transferred to a dehydration tank for dehydration, and 0.3 g of phosphoric acid was added to 1000 g of water, followed by washing of the dehydrated product. The washed solid was put in a mixer-type vacuum dryer and dried to obtain 304 g of crystalline powder, and 1000 g of a dehydration filtrate (20 wt% of copper concentration). A yield of 95.4% was confirmed as compared with 318 g of theory. According to the KS standard chemical quantitative analysis, the content of cuprous chloride was 99.6% in the crystalline powder, Fe was 10ppm, Na was 12ppm, and Pb was not detected. In addition, the copper concentration in the washing wastewater was 0.93%.

Comparative Example 1

1000 g of etching waste solution (Cu 10% by weight), 200 g of NaCl (95% or more), 125 g of copper powder (3.5% by weight of Fe, 80% by weight of Cu), and 300 g of water were added thereto, reacted at 100 ° C, and filtered to separate insoluble materials. . Water was added to the filtrate to crystallize, dehydrated, washed and dried in vacuo to give 252 g of a dry cake. The yield was 79.2%. Copper chloride content in the dry cake was 97.5%, Na was 730ppm, Fe was 59ppm, Pb was 15ppm.

Comparative Example 2

1000 g of etching waste liquid (Cu 10% by weight) was concentrated at 80 ° C to obtain 805 g of etching waste liquid having a copper concentration of 12.4%. 45 g of iron (99%) was added to the solution, followed by reduction, followed by filtration. The filtrate was cooled to 20 ° C, dehydrated, washed, immersed in methanol, and dried to obtain 70.1 g of cuprous chloride. The yield was 44.9% (1st), the cuprous chloride content in the dry cake was 99.5%, 207ppm Fe, 35ppm Na, 5ppm. Subsequently, the dehydration solution was diluted with water, followed by secondary crystallization, filtration, dipping methanol (100 g), filtration, and drying to obtain 59.0 g of cuprous chloride. The yield was 37.8% (secondary), the cuprous chloride content in the dry cake was 99.0%, 88ppm Fe, 15ppm Na, 2ppm Pb. The total yield was 82.7%.

Comparing Examples 1 and 2 with Comparative Examples 1 and 2, it was confirmed that the content of cuprous chloride contained in the final dried product was higher than that of Comparative Examples 1 and 2 in Examples 1 and 2. In the yield of cuprous chloride, Example 2 was 95.4%, which is much higher than 79.2% and 82.7% of Comparative Examples 1 and 2.

Therefore, by using the method / system for producing cuprous chloride from the copper waste liquid of the present invention, it is possible to more easily produce a large amount of cuprous copper with high purity.

Specific embodiments of the present invention have been presented above, but the present invention is not limited to the above, and various modifications can be made within the technical spirit of the present invention, and such modifications will belong to the following claims.

1 is a flowchart showing a method for producing cuprous chloride according to the present invention.

2 is a view showing an example of the cuprous chloride production system of the present invention.

<Explanation of symbols for the main parts of the drawings>

10: reactor

20: strainer

30: thickening tank

34: condenser

36: heat exchanger

40: cooling tank

50: dehydration tank

52: dehydration return line

60: dryer

70: waste hydrochloric acid recovery tank

72: waste hydrochloric acid return line

Claims (10)

Reacting the copper waste solution with hydrochloric acid and a reducing agent; Filtering the reaction solution to remove the filtered insoluble matter; Concentrating the filtrate filtered in the filtration step; Cooling the concentrated solution concentrated in the concentration step; Dewatering the cooled product cooled in the cooling step; Washing the dehydrated dehydrated in the dehydration step; And Drying the washings washed in the washing step to obtain cuprous chloride; method for producing cuprous chloride from copper waste liquid comprising the. The method according to claim 1, The reducing agent is a method for producing cuprous chloride from copper waste liquid, characterized in that at least one selected from the group consisting of copper, iron, zinc and hydrazine. The method according to claim 1, The reaction step is made at 70 to 110 ℃, the concentration step is made at 70 to 90 ℃, the cooling step is a method for producing cuprous chloride from the copper waste liquid, characterized in that made in 60 ℃ or less. The method according to claim 1, Hydrochloric acid distilled and condensed in the concentration step is re-administered to the reaction step, the method for producing cuprous chloride from copper waste liquid. The method according to claim 1 or 4, The method for producing cuprous chloride from copper waste liquid, characterized in that the dehydration liquid dehydrated in the dehydration step is re-administered to the reaction step. The method according to claim 1 or 4, The method for producing cuprous chloride from copper waste fluid, characterized in that the washing step in the washing step to the antioxidant administration water. A reaction tank 10 in which copper waste solution, hydrochloric acid, and a reducing agent are administered to react; A filter 20 for filtering insoluble materials after completion of the reaction in the reactor 10; A concentration tank 30 for concentrating the filtrate filtered through the filter 20; A cooling tank 40 for cooling the concentrated liquid concentrated in the concentration tank 30; Dehydration tank (50) for dehydrating and washing the crystallized crystallization in the cooling tank (40); And And a dryer (60) for drying the dewatered cake dehydrated in the dehydration tank (50). The method of claim 7, Further comprising a waste hydrochloric acid recovery tank (70) for recovering the waste hydrochloric acid distilled in the concentration tank (30) and condensed through the condenser (34), to return the hydrochloric acid of the waste hydrochloric acid recovery tank 70 to the reaction tank (10) The system for producing cuprous chloride from copper waste liquid, characterized in that it further comprises a waste hydrochloric acid return line (72). The method according to claim 7 or 8, And a dehydration liquid conveying line (52) for returning the dehydration liquid dehydrated in said dehydration tank (50) to said reactor (10). The method according to claim 7 or 8, The heat exchanger 36 is installed outside the concentration tank 30, and the liquid in the concentration tank 30 is transferred to the heat exchanger 36 by a pump installed outside the concentration tank 30, and then transferred to the concentration tank 30 and circulated. A system for producing cuprous chloride from copper waste fluid, characterized in that the.

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