Preparation method and purification process of copper hydroxide

Abstract

The application discloses a preparation method and purification process of copper hydroxide, a certain amount of anhydrous copper sulfate is accurately weighed, and a certain volume of deionized water is added to prepare a solution with a certain concentration, a copper ammonia solution is prepared: slurry is prepared from circuit board sludge, screening is performed, ammonium bicarbonate or ammonium carbonate is added for reaction, and a copper ammonia solution containing carbonate or bicarbonate is obtained through purification; in addition, high-purity copper powder is added into concentrated ammonia water, concentrated hydrogen peroxide solution is slowly dropped into the concentrated ammonia water, and the dropping is continued until no large amount of bubbles is generated in the solution, and the solution is filtered to obtain a clear indigo blue solution. The production process adds the step of adding a stabilizer and stirring, guarantees the stable state of the copper hydroxide crystal, and enables the copper hydroxide crystal to remain unchanged into copper oxide for one year in an environment with a temperature as high as 60 degrees.

Description

Technical Field

[0001] This invention relates to the field of copper hydroxide preparation technology, and more specifically, to a method for preparing and purifying copper hydroxide. Background Technology

[0002] Copper hydroxide has various commercial uses, serving as an important catalyst, pigment, chemical raw material, and pesticide ingredient. In agricultural production, copper hydroxide is an inorganic copper-based fungicide in copper preparations and a major component of the fungicide Bordeaux mixture. The application prospects of copper hydroxide products are broad. However, copper hydroxide itself is thermodynamically unstable and easily decomposes into copper oxide even at room temperature. Therefore, effective modification is necessary to extend its shelf life. Currently, the main methods for treating etching waste liquid include chemical precipitation, flocculation precipitation, solvent extraction, and electrolysis. Among these, chemical precipitation is widely used as the simplest and most economical method, but it suffers from problems such as low purity of the recovered product and improper reaction control. Furthermore, copper hydroxide has various commercial uses, serving as an important catalyst, pigment, chemical raw material, and pesticide ingredient. In agricultural production, copper hydroxide is an inorganic copper-based fungicide in copper preparations and a major component of the fungicide Bordeaux mixture. The application prospects of copper hydroxide products are broad. However, copper hydroxide itself is thermodynamically unstable and easily decomposes into copper oxide even at room temperature. Therefore, effective modification is necessary to extend the shelf life of copper hydroxide. Existing technologies offer limited improvements in thermal stability, only guaranteeing that it will not turn black for 2 hours. Furthermore, the limited market volume of alkaline etching waste liquid hinders large-scale production. Summary of the Invention

[0003] In view of the problems existing in the prior art, the present invention provides a method for preparing copper hydroxide and a purification process to solve the technical problems mentioned in the background art. Technical solution

[0004] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing copper hydroxide and a purification process, comprising the following steps: Step 1: Accurately weigh a certain amount of anhydrous copper sulfate and add a certain volume of deionized water to prepare a solution of a certain concentration to prepare a copper ammonia solution: Pulp and sieve the circuit board sludge, add ammonium bicarbonate or ammonium carbonate to react, and purify to obtain a copper ammonia solution containing carbonate or bicarbonate. In addition, add high-purity copper powder to concentrated ammonia water, slowly add concentrated hydrogen peroxide solution until the solution no longer produces a large number of bubbles, filter the solution to obtain a clear indigo blue solution. Step 2: Select titanium plates of the appropriate size and place them in a degreasing agent. Degrease them at room temperature for 30 minutes. Remove them, rinse them clean, and place them in a boiling oxalic acid solution. Heat the solution and maintain a gentle boil for 2 hours. Remove the plates, rinse them thoroughly with water, then rinse them with pure water, and finally rinse them with anhydrous ethanol solution. Let them air dry naturally, then wrap them in filter paper for later use. Add water to the neutralization tank and heat it to 70°C. Then, add acidic etching waste liquid and alkaline etching waste liquid to the neutralization tank in proportion. Use a flow meter to control the pH value of the etching waste liquid in the neutralization tank to between 5 and 5.5. The process is carried out through reaction precipitation. Step 3: Simultaneously pass the precipitate and waste liquid in the sedimentation tank into the filter press for dehydration. Add the filtered filter cake to the reaction vessel. Dissolve the metal salts in the selected solvent according to the stoichiometric ratio to ensure that all components are mixed evenly. Use a brush to evenly coat the pretreated titanium plate with the coating solution. Then, place the titanium plate under an infrared lamp to dry for 10 minutes to allow the solvent to evaporate completely. Next, place the titanium plate in a muffle furnace at a set temperature for oxidation and sintering for 10 minutes. Remove the plate, air cool it, and repeat the coating, drying, oxidation, and sintering steps until the coating solution is used up. Finally, perform oxidation and sintering for 1 hour to produce the DSA anode. Step 4: Add NaOH to adjust the pH of the solution, accelerate the release of ammonia gas, freeze the solution, and dry it using a freeze dryer to obtain a pure blue solid. Prepare copper hydroxide precursor: Add the purified acidic etching waste liquid to the purified copper ammonia solution, control the pH of the reaction endpoint to 4.0-5.0, separate the solid and liquid phases, and the solid phase is the copper hydroxide precursor. Ammonia conversion reaction: Add water to the copper hydroxide precursor to make a slurry, add ammonia water, adjust and maintain the reaction pH to 10-12, the reaction temperature to 20-60℃, react for 1-2 hours, separate the solid and liquid phases, and wash the solid until the pH of the effluent is 9-10 to obtain wet copper hydroxide. Step 5: Modified copper hydroxide: Wet copper hydroxide is slurried with water, and hypophosphite solution is added for modification reaction. The hypophosphite solution reacts with copper hydroxide to form copper hypophosphite covering the surface of copper hydroxide. After solid-liquid separation, it is dried at low temperature to obtain modified copper hydroxide. The mass ratio of total copper in wet copper hydroxide to total phosphorus in hypophosphite solution in step 4 is 800-1600:1.

[0005] The present invention is further configured such that the metal salt is one of oxalic acid, thiophosphate, thiocarbamate or sulfide hydroxyboronic acid, and the solvent in step two is hydrochloric acid solution.

[0006] The present invention is further configured such that the mass ratio of total copper in the wet copper hydroxide product to total phosphorus in the hypophosphite solution is 900-1200:1.

[0007] The present invention is further configured such that the reaction pH is 7.0-8.5, the reaction temperature is 30-50℃, and the reaction time is 2-3h.

[0008] The present invention is further configured such that the preparation method of the acidic etching waste liquid after impurity removal in step two is as follows: add alkaline etching waste liquid or ammonia water to the acidic etching waste liquid, adjust the pH value to 1.5-2.0, add solid iron hydroxide at a solid-liquid ratio of 1:1000-10000, stir for 10-30 minutes, separate the solid and liquid, and obtain the acidic etching waste liquid after impurity removal.

[0009] The present invention is further configured such that the concentration of concentrated ammonia in step one is 25%-30%.

[0010] The present invention is further configured such that the concentration of concentrated hydrogen peroxide in step one is 20%-30%.

[0011] The present invention is further configured such that, before step one, an oxidant is added to the acidic etching waste liquid to oxidize the cuprous and ferrous ions in the acidic etching waste liquid, and then activated carbon is added. After sedimentation and stratification, the supernatant is taken and filtered to obtain the impurity-removed acidic etching waste liquid; soluble magnesium salt is added to the alkaline etching waste liquid to react, and after sedimentation and stratification, the supernatant is taken and filtered to obtain the impurity-removed alkaline etching waste liquid.

[0012] The present invention is further configured such that the alkaline water is a sodium hydroxide solution with a concentration of 20 wt% and the volume-to-weight ratio of the sodium hydroxide solution to copper sulfate crystals is (1.2-1.3) L:1 Kg.

[0013] The present invention is further configured such that the phosphorus content in the ion exchange liquid of the chemical nickel waste is 15000-25000 mg / L. Beneficial effects

[0014] Compared with the prior art, the present invention provides a method for preparing copper hydroxide and a purification process, which has the following beneficial effects: This production process adds a step of adding a stabilizer and stirring, ensuring the stability of the copper hydroxide crystals. This allows them to remain in a stable state for up to one year without turning into copper oxide, even at temperatures as high as 60 degrees Celsius. The copper hydroxide produced by this invention has a purity of up to 99.5%, and the resulting copper hydroxide particles are relatively fine, suitable for laboratory analysis reactions. The preparation cost is low, the process is simple, and the production process generates little waste that can be recycled, resulting in minimal environmental pollution. Furthermore, using ammonium bicarbonate or ammonium carbonate complexed ammonia leaching to extract copper from circuit board sludge allows impurities such as calcium, iron, and lead to remain in the solid phase as carbonates, achieving effective separation of copper from other impurity ions. Adjusting the pH of the complexed ammonia leaching solution containing bicarbonate or carbonate with the acid etching waste solution after impurity removal effectively removes bicarbonate or carbonate ions and forms a copper precursor, which helps ensure the purity of the subsequent copper hydroxide product. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall process for preparing and purifying copper hydroxide. Detailed Implementation

[0016] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0017] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0018] In this invention, unless otherwise stated, the directional terms such as "up" and "down" generally refer to the directions shown in the accompanying drawings, or to the vertical, perpendicular, or gravitational direction; similarly, for ease of understanding and description, "left" and "right" generally refer to the left and right shown in the accompanying drawings; "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention. Example

[0019] Please see Figure 1 A method for preparing and purifying copper hydroxide includes the following steps: Step 1: Accurately weigh a certain amount of anhydrous copper sulfate and add a certain volume of deionized water to prepare a solution of a certain concentration to prepare a copper ammonia solution: Pulp and sieve the circuit board sludge, add ammonium bicarbonate or ammonium carbonate to react, and purify to obtain a copper ammonia solution containing carbonate or bicarbonate. In addition, add high-purity copper powder to concentrated ammonia water, slowly add concentrated hydrogen peroxide solution until the solution no longer produces a large number of bubbles, filter the solution to obtain a clear indigo blue solution. Step 2: Select titanium plates of the appropriate size and place them in a degreasing agent. Degrease them at room temperature for 30 minutes. Remove them, rinse them clean, and place them in a boiling oxalic acid solution. Heat the solution and maintain a gentle boil for 2 hours. Remove the plates, rinse them thoroughly with water, then rinse them with pure water, and finally rinse them with anhydrous ethanol solution. Let them air dry naturally, then wrap them in filter paper for later use. Add water to the neutralization tank and heat it to 70°C. Then, add acidic etching waste liquid and alkaline etching waste liquid to the neutralization tank in proportion. Use a flow meter to control the pH value of the etching waste liquid in the neutralization tank to between 5 and 5.5. The process is carried out through reaction precipitation. Step 3: Simultaneously pass the precipitate and waste liquid in the sedimentation tank into the filter press for dehydration. Add the filtered filter cake to the reaction vessel. Dissolve the metal salts in the selected solvent according to the stoichiometric ratio to ensure that all components are mixed evenly. Use a brush to evenly coat the pretreated titanium plate with the coating solution. Then, place the titanium plate under an infrared lamp to dry for 10 minutes to allow the solvent to evaporate completely. Next, place the titanium plate in a muffle furnace at a set temperature for oxidation and sintering for 10 minutes. Remove the plate, air cool it, and repeat the coating, drying, oxidation, and sintering steps until the coating solution is used up. Finally, perform oxidation and sintering for 1 hour to produce the DSA anode. Step 4: Add NaOH to adjust the pH of the solution, accelerate the release of ammonia gas, freeze the solution, and dry it using a freeze dryer to obtain a pure blue solid. Prepare copper hydroxide precursor: Add the purified acidic etching waste liquid to the purified copper ammonia solution, control the reaction endpoint pH to 4.0, separate the solid and liquid phases, and the solid phase is the copper hydroxide precursor. Ammonia conversion reaction: Add water to the copper hydroxide precursor to make a slurry, add ammonia water, adjust and maintain the reaction pH to 10, the reaction temperature to 20℃, react for 1 hour, separate the solid and liquid phases, wash the solid until the pH of the effluent is 9, and obtain wet copper hydroxide. Step 5: Modified copper hydroxide: Wet copper hydroxide is slurried with water, and hypophosphite solution is added for modification reaction. The hypophosphite solution reacts with copper hydroxide to form copper hypophosphite covering the surface of copper hydroxide. After solid-liquid separation, it is dried at low temperature to obtain modified copper hydroxide. The mass ratio of total copper in wet copper hydroxide to total phosphorus in hypophosphite solution in step 4 is 800-1600:1.

[0020] In a further embodiment of the present invention, the metal salt is one of oxalic acid, thiophosphate, thiocarbamate or sulfide hydroxyboronic acid, and the solvent in step two is hydrochloric acid solution.

[0021] In a further embodiment of the present invention, the mass ratio of total copper in the wet copper hydroxide product to total phosphorus in the hypophosphite solution is 900-1200:1.

[0022] In a further embodiment of the present invention, the reaction pH is 7.0, the reaction temperature is 30°C, and the reaction time is 2 hours. Example

[0023] Please see Figure 1 A method for preparing and purifying copper hydroxide includes the following steps: Step 1: Accurately weigh a certain amount of anhydrous copper sulfate and add a certain volume of deionized water to prepare a solution of a certain concentration to prepare a copper ammonia solution: Pulp and sieve the circuit board sludge, add ammonium bicarbonate or ammonium carbonate to react, and purify to obtain a copper ammonia solution containing carbonate or bicarbonate. In addition, add high-purity copper powder to concentrated ammonia water, slowly add concentrated hydrogen peroxide solution until the solution no longer produces a large number of bubbles, filter the solution to obtain a clear indigo blue solution. Step 2: Select titanium plates of the appropriate size and place them in a degreasing agent. Degrease them at room temperature for 30 minutes. Remove them, rinse them clean, and place them in a boiling oxalic acid solution. Heat the solution and maintain a gentle boil for 2 hours. Remove the plates, rinse them thoroughly with water, then rinse them with pure water, and finally rinse them with anhydrous ethanol solution. Let them air dry naturally, then wrap them in filter paper for later use. Add water to the neutralization tank and heat it to 70°C. Then, add acidic etching waste liquid and alkaline etching waste liquid to the neutralization tank in proportion. Use a flow meter to control the pH value of the etching waste liquid in the neutralization tank to between 5 and 5.5. The process is carried out through reaction precipitation. Step 3: Simultaneously pass the precipitate and waste liquid in the sedimentation tank into the filter press for dehydration. Add the filtered filter cake to the reaction vessel. Dissolve the metal salts in the selected solvent according to the stoichiometric ratio to ensure that all components are mixed evenly. Use a brush to evenly coat the pretreated titanium plate with the coating solution. Then, place the titanium plate under an infrared lamp to dry for 10 minutes to allow the solvent to evaporate completely. Next, place the titanium plate in a muffle furnace at a set temperature for oxidation and sintering for 10 minutes. Remove the plate, air cool it, and repeat the coating, drying, oxidation, and sintering steps until the coating solution is used up. Finally, perform oxidation and sintering for 1 hour to produce the DSA anode. Step 4: Add NaOH to adjust the pH of the solution, accelerate the release of ammonia gas, freeze the solution, and dry it using a freeze dryer to obtain a pure blue solid. Prepare copper hydroxide precursor: Add the purified acidic etching waste liquid to the purified copper ammonia solution, control the reaction endpoint pH to 5.0, separate the solid and liquid phases, the solid phase is the copper hydroxide precursor, ammonia conversion reaction: Add water to the copper hydroxide precursor to make a slurry, add ammonia water, adjust and maintain the reaction pH to 12, the reaction temperature to 60℃, react for 2 hours, separate the solid and liquid phases, wash the solid until the pH of the effluent is 10, and obtain wet copper hydroxide. Step 5: Modified copper hydroxide: Wet copper hydroxide is slurried with water, and hypophosphite solution is added for modification reaction. The hypophosphite solution reacts with copper hydroxide to form copper hypophosphite covering the surface of copper hydroxide. After solid-liquid separation, it is dried at low temperature to obtain modified copper hydroxide. The mass ratio of total copper in wet copper hydroxide to total phosphorus in hypophosphite solution in step 4 is 800-1600:1.

[0024] In a further embodiment of the present invention, the preparation method of the acidic etching waste liquid after impurity removal in step two is as follows: add alkaline etching waste liquid or ammonia water to the acidic etching waste liquid, adjust the pH value to 1.5, add ferric hydroxide solid at a solid-liquid ratio of 1:1000-10000, stir for 10 minutes, separate the solid and liquid to obtain the acidic etching waste liquid after impurity removal; the concentration of concentrated ammonia water in step one is 25%; the concentration of concentrated hydrogen peroxide in step one is 20%; before step one, add an oxidant to the acidic etching waste liquid to oxidize the cuprous ions and ferrous ions in the acidic etching waste liquid, then add activated carbon, after sedimentation and stratification, take the supernatant for filtration treatment to obtain the acidic etching waste liquid after impurity removal; Soluble magnesium salts are added to alkaline etching waste liquid to react. After sedimentation and stratification, the supernatant is taken and filtered to obtain the purified alkaline etching waste liquid.

[0025] In a further embodiment of the present invention, the alkaline water is a sodium hydroxide solution with a concentration of 20 wt% and a volume-to-weight ratio of sodium hydroxide solution to copper sulfate crystals of (1.2-1.3) L:1 Kg; the phosphorus content in the ion exchange liquid of the chemical nickel waste liquid is 15000 mg / L.

[0026] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing and purifying copper hydroxide, characterized in that, Includes the following steps: Step 1: Accurately weigh a certain amount of anhydrous copper sulfate and add a certain volume of deionized water to prepare a solution of a certain concentration to prepare a copper ammonia solution: Pulp and sieve the circuit board sludge, add ammonium bicarbonate or ammonium carbonate to react, and purify to obtain a copper ammonia solution containing carbonate or bicarbonate. In addition, add high-purity copper powder to concentrated ammonia water, slowly add concentrated hydrogen peroxide solution until the solution no longer produces a large number of bubbles, filter the solution to obtain a clear indigo blue solution. Step 2: Select titanium plates of the appropriate size and place them in a degreasing agent. Degrease them at room temperature for 30 minutes. Remove them, rinse them clean, and place them in a boiling oxalic acid solution. Heat the solution and maintain a gentle boil for 2 hours. Remove the plates, rinse them thoroughly with water, then rinse them with pure water, and finally rinse them with anhydrous ethanol solution. Let them air dry naturally, then wrap them in filter paper for later use. Add water to the neutralization tank and heat it to 70°C. Then, add acidic etching waste liquid and alkaline etching waste liquid to the neutralization tank in proportion. Use a flow meter to control the pH value of the etching waste liquid in the neutralization tank to between 5 and 5.

5. The process is carried out through reaction precipitation. Step 3: Simultaneously pass the precipitate and waste liquid in the sedimentation tank into the filter press for dehydration. Add the filtered filter cake to the reaction vessel. Dissolve the metal salts in the selected solvent according to the stoichiometric ratio to ensure that all components are mixed evenly. Use a brush to evenly coat the pretreated titanium plate with the coating solution. Then, place the titanium plate under an infrared lamp to dry for 10 minutes to allow the solvent to evaporate completely. Next, place the titanium plate in a muffle furnace at a set temperature for oxidation and sintering for 10 minutes. Remove the plate, air cool it, and repeat the coating, drying, oxidation, and sintering steps until the coating solution is used up. Finally, perform oxidation and sintering for 1 hour to produce the DSA anode. Step 4: Add NaOH to adjust the pH of the solution, accelerate the release of ammonia gas, freeze the solution, and dry it using a freeze dryer to obtain a pure blue solid. Prepare copper hydroxide precursor: Add the purified acidic etching waste liquid to the purified copper ammonia solution, control the pH of the reaction endpoint to 4.0-5.0, separate the solid and liquid phases, and the solid phase is the copper hydroxide precursor. Ammonia conversion reaction: Add water to the copper hydroxide precursor to make a slurry, add ammonia water, adjust and maintain the reaction pH to 10-12, the reaction temperature to 20-60℃, react for 1-2 hours, separate the solid and liquid phases, and wash the solid until the pH of the effluent is 9-10 to obtain wet copper hydroxide. Step 5: Modified copper hydroxide: Wet copper hydroxide is slurried with water, and hypophosphite solution is added for modification reaction. The hypophosphite solution reacts with copper hydroxide to form copper hypophosphite covering the surface of copper hydroxide. After solid-liquid separation, it is dried at low temperature to obtain modified copper hydroxide. The mass ratio of total copper in wet copper hydroxide to total phosphorus in hypophosphite solution in step 4 is 800-1600:

1.

2. The method for preparing and purifying copper hydroxide according to claim 1, characterized in that: The metal salt is one of oxalic acid, thiophosphate, thiocarbamate, or sulfide-based boronic acid, and the solvent in step two is hydrochloric acid solution.

3. The method for preparing and purifying copper hydroxide according to claim 1, characterized in that: The mass ratio of total copper in the wet copper hydroxide product to total phosphorus in the hypophosphite solution is 900-1200:

1.

4. The method for preparing and purifying copper hydroxide according to claim 3, characterized in that: The reaction is carried out at a pH of 7.0-8.5, a temperature of 30-50℃, and a time of 2-3 hours.

5. The method for preparing and purifying copper hydroxide according to claim 4, characterized in that: The preparation method of the acidic etching waste liquid after impurity removal in step two is as follows: add alkaline etching waste liquid or ammonia water to the acidic etching waste liquid, adjust the pH value to 1.5-2.0, add solid iron hydroxide at a solid-liquid ratio of 1:1000-10000, stir for 10-30 minutes, separate the solid and liquid, and obtain the acidic etching waste liquid after impurity removal.

6. The method for preparing and purifying copper hydroxide according to claim 5, characterized in that: The concentration of concentrated ammonia in step one is 25%-30%.

7. The method for preparing and purifying copper hydroxide according to claim 6, characterized in that: The concentration of concentrated hydrogen peroxide in step one is 20%-30%.

8. The method for preparing and purifying copper hydroxide according to claim 7, characterized in that: in Before step one, an oxidant is added to the acidic etching waste liquid to oxidize the cuprous and ferrous ions in the acidic etching waste liquid, and then activated carbon is added. After sedimentation and stratification, the supernatant is taken and filtered to obtain the purified acidic etching waste liquid. Soluble magnesium salt is added to the alkaline etching waste liquid to react. After sedimentation and stratification, the supernatant is taken and filtered to obtain the purified alkaline etching waste liquid.

9. The method for preparing and purifying copper hydroxide according to claim 7, characterized in that: The alkaline solution is a sodium hydroxide solution with a concentration of 20 wt%, and the volume-to-weight ratio of the sodium hydroxide solution to copper sulfate crystals is 1.2-1.3 L: 1 kg.

10. The method for preparing and purifying copper hydroxide according to claim 7, characterized in that: The phosphorus content in the ion exchange liquid of the chemical nickel waste is 15,000-25,000 mg / L.

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