A comprehensive utilization method of etching liquid

Abstract

The present invention relates to a comprehensive utilization method of etching liquid, the comprehensive utilization method comprising: mixing an acidic etching liquid and an alkaline etching liquid, then adding an auxiliary agent, and sequentially performing heat preservation treatment and solid-liquid separation to obtain basic copper chloride; the auxiliary agent comprises an amino acid and hexadecyltrimethylammonium chloride. The comprehensive utilization method provided by the present invention directly neutralizes the acid and alkaline etching liquids in a coordinated manner, and then completely recovers the metal ions through auxiliary agent assistance and promotion to precipitate in the form of basic copper chloride, and the synthesized basic copper chloride has excellent morphology, particle size and other properties, and the filtrate is then subjected to subsequent treatment to finally classify and recover the remaining components to obtain other by-products, thereby realizing resource processing and efficient recovery of each component in the acid and alkaline etching liquids, and no secondary waste and secondary pollution occur during the process.

Description

Technical Field

[0001] The invention relates to the technical field of recycling and processing of PCB etching liquid, and relates to a comprehensive utilization method of the etching liquid. Background Art

[0002] At present, PCB is an important support for electronic products and plays a role in connecting electronic components. Its production process is relatively complicated. The copper etching process, as an important link in the production process, plays a key role in the PCB industry. The principle of the PCB etching process is to use metal Cu and Cu in the etching solution to form a copper etchant. 2+ The chemical reaction will corrode the excess metal on the copper plate. As the etching reaction proceeds, the amount of dissolved copper increases and the 2+ As the concentration decreases, the etching ability of the etching solution also decreases. It can no longer meet the etching reaction requirements and gradually loses its etching ability, eventually resulting in a huge amount of copper-containing etching waste liquid.

[0003] Acidic copper chloride etching solution and alkaline copper-containing etching solution are also waste liquids derived from the PCB etching process. Acidic copper chloride etching solution contains HCl / CuCl 2 NH 4 Cl / CuCl 2 、HCl / CuCl 2 / NaCl and other systems, among which HCl / CuCl 2 / NaCl system is more common. The composition of alkaline copper chloride etching solution is relatively simple, generally composed of NH 4 Cl / CuCl 2 / NH 3 ·H 2 O. Acid and alkaline etching solutions contain nearly 10% copper, and most of the copper in acid etching solutions is in the form of CuCl 4 2- The alkaline etching solution mainly exists in the form of Cu(NH 3 ) 4 2+ The high content of valuable metals in etching solutions makes them have great potential for resource conversion and utilization. However, other components in them cause the subsequent secondary solids and impurities in wastewater to be diverse and high in content, making them difficult to handle, with limited resource utilization or low recycling value.

[0004] At present, it is common to use the neutralization method to treat acid and alkaline etching solutions, that is, adding alkaline solution to the etching solution to convert copper ions into black copper oxide precipitates, and then the tail water is aerated to deammoniate and distill sodium chloride. This traditional method is acceptable for copper resource utilization, but the process consumes a lot of reagents, the total amount of tail water is large, and the resource value of other components is also low.

[0005] For example, CN109455753A discloses a recycling process for etching liquid, which includes the following steps: S1, preparation of sodium carbonate solution: dissolving sodium carbonate solid in a certain mass of water to obtain sodium carbonate solution, and placing the prepared sodium carbonate solution in a reaction vessel, and the mass ratio of sodium carbonate to water in the sodium carbonate solution is 1:2.5-3.5, and the temperature of the sodium carbonate solution is maintained at 30-40°C; S2, dripping of acidic etching solution: dripping acidic etching solution into the reaction vessel, using a stirrer to stir the liquid in the reaction vessel while dripping the acidic etching solution, and maintaining the reaction temperature in the reaction vessel at 30-50°C, and the pH value at the end of the reaction is 7.5-8.5; S3, standing and settling: stopping stirring and standing to obtain basic copper carbonate precipitation; S4, recovering basic copper carbonate: taking out the basic copper carbonate precipitated in the reaction vessel, washing and drying, and obtaining a basic copper carbonate product. This scheme can effectively reduce the copper ion concentration in the acidic etching solution wastewater and realize the recovery of copper resources.

[0006] Based on this, there are technical attempts to mix acid and alkaline etching solutions to precipitate copper and then produce copper sulfate, such as CN104556467A discloses a method for treating etching waste liquid and its treatment equipment. The method for treating etching waste liquid according to the present invention includes: mixing acidic etching waste liquid with alkaline etching waste liquid; adjusting the pH value of the mixed etching waste liquid and heating it to cause a neutralization reaction; separating the precipitate and the filtrate; and adding a flocculant to the filtrate to flocculate the suspended particles and the suspended colloidal arsenic in the filtrate. According to this scheme, it is possible to treat etching waste liquid in large quantities in a simple and low-cost manner, realize the recycling and reuse of copper and ammonia, and reduce the COD of the etching waste liquid to below 40 mg / L, and the arsenic content to below 0.8 ppm, thereby meeting the wastewater discharge standards prescribed by the state.

[0007] Although this method can reduce the dosage of reagents to a certain extent, the precipitate is rich in impurities and difficult to remove by simple water washing, which will inevitably affect the quality of subsequent copper salts. At the same time, a small amount of copper ions still remain in the precipitation filtrate and are in a complex state. Therefore, it is necessary to introduce reducing agents such as hydrazine hydrate and sulfiding agent to remove them, which also restricts the harmless disposal of tail water. That is, the current comprehensive recycling of acidic and alkaline etching solutions still has the problems of low utilization rate and difficult tail water treatment. Summary of the invention

[0008] In view of the problems existing in the prior art, the object of the present invention is to provide a comprehensive utilization method of etching solution, by which the efficient conversion of copper element in the etching solution is achieved, so that the obtained basic copper chloride has a specific rhombus structure, thereby achieving efficient utilization of waste etching solution.

[0009] To achieve this object, the present invention adopts the following technical solutions:

[0010] The present invention provides a comprehensive utilization method of etching solution, the comprehensive utilization method comprising:

[0011] The acidic etching solution and the alkaline etching solution are mixed, and then an auxiliary agent is added, and then heat preservation treatment and solid-liquid separation are performed in sequence to obtain basic copper chloride;

[0012] The auxiliary agent includes amino acid and hexadecyltrimethylammonium chloride.

[0013] The comprehensive utilization method provided by the present invention directly neutralizes the acid and alkaline etching solutions in a coordinated manner, and then completely recovers the metal ions through auxiliary agent assistance and promotion to precipitate in the form of basic cupric chloride, and the synthesized basic cupric chloride has excellent properties such as morphology and particle size, and the filtrate is subsequently treated to finally classify and recover the remaining components to obtain other by-products, thereby realizing resource processing and efficient recovery of various components in the acid and alkaline etching solutions, and no secondary waste and secondary pollution occur in the process.

[0014] As a preferred technical solution of the present invention, the acidic etching solution is heated and stirred before mixing.

[0015] Preferably, the heating and stirring temperature is 50-60°C, for example, it can be 50°C, 51°C, 52°C, 53°C, 54°C, 55°C, 56°C, 57°C, 58°C, 59°C or 60°C, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0016] Preferably, the heating and stirring time is 20-30 min, for example, it can be 20 min, 21 min, 22 min, 23 min, 24 min, 25 min, 26 min, 27 min, 28 min, 29 min or 30 min, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0017] As a preferred technical solution of the present invention, the end point of the mixing is a pH value of the material of 6-7, for example, it can be 6, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9 or 7, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0018] As a preferred technical solution of the present invention, the mass ratio of amino acid to hexadecyltrimethylammonium chloride in the auxiliary agent is (1.5-2):1, for example, it can be 1.5:1, 1.55:1, 1.6:1, 1.65:1, 1.7:1, 1.75:1, 1.8:1, 1.85:1, 1.9:1, 1.95:1 or 2:1, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0019] Preferably, the mass concentration of the auxiliary agent is 0.5-1%, for example, it can be 0.5%, 0.55%, 0.6%, 0.65%, 0.7%, 0.75%, 0.8%, 0.85%, 0.9%, 0.95% or 1%, etc., but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0020] As a preferred technical solution of the present invention, the amount of the additive added is 0.2-0.5% of the volume of the material obtained after mixing, for example, it can be 0.2%, 0.22%, 0.24%, 0.26%, 0.28%, 0.3%, 0.32%, 0.34%, 0.36%, 0.38%, 0.4%, 0.42%, 0.44%, 0.46%, 0.48% or 0.5%, etc., but is not limited to the listed values, and other values ​​not listed within the range are also applicable.

[0021] Preferably, the addition rate of the auxiliary agent is 5-10 L / min, for example, it can be 5 L / min, 5.5 L / min, 6 L / min, 6.5 L / min, 7 L / min, 7.5 L / min, 8 L / min, 8.5 L / min, 9 L / min, 9.5 L / min or 10 L / min, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0022] Preferably, the temperature of the insulation treatment is 70-80°C, for example, it can be 70°C, 71°C, 72°C, 73°C, 74°C, 75°C, 76°C, 77°C, 78°C, 79°C or 80°C, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0023] Preferably, the insulation treatment time is 1-2h, for example, it can be 1h, 1.1h, 1.2h, 1.3h, 1.4h, 1.5h, 1.6h, 1.7h, 1.8h, 1.9h or 2h, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0024] As a preferred technical solution of the present invention, the temperature of the material in the solid-liquid separation is 40-50°C, for example, it can be 40°C, 42°C, 44°C, 46°C, 48°C or 50°C, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0025] Preferably, the basic copper chloride obtained by the solid-liquid separation is washed.

[0026] Preferably, the solid-to-liquid ratio g / mL in the washing is 1:(1.5-2), for example, it can be 1:1.5, 1:1.55, 1:1.6, 1:1.65, 1:1.7, 1:1.75, 1:1.8, 1:1.85, 1:1.9, 1:1.95 or 1:2, etc., but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0027] Preferably, the washing time is 1-2h, for example, it can be 1h, 1.1h, 1.2h, 1.3h, 1.4h, 1.5h, 1.6h, 1.7h, 1.8h, 1.9h or 2h, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0028] As a preferred technical solution of the present invention, the washing water obtained from the washing and the filtrate obtained from the solid-liquid separation are mixed to obtain a liquid to be treated.

[0029] Preferably, the liquid to be treated is deaminated to obtain a deaminated liquid, and then the deaminated liquid is treated with a bipolar membrane to obtain an acid solution and an alkaline solution, which are returned to the preparation process for secondary utilization as a pH adjuster.

[0030] As a preferred technical solution of the present invention, the pH value of the material in the deamination process is 9-10, for example, it can be 9, 9.1, 9.2, 9.3, 9.4, 9.5, 9.6, 9.7, 9.8, 9.9 or 10, but is not limited to the listed values, and other values ​​not listed within the range are also applicable.

[0031] Preferably, the deamination is carried out by pulse electrolysis, the anode comprises a graphite electrode, and the cathode comprises a stainless steel electrode.

[0032] Preferably, the frequency of the pulses in the deamination is 600-800 Hz, for example, it can be 600 Hz, 610 Hz, 620 Hz, 630 Hz, 640 Hz, 650 Hz, 660 Hz, 670 Hz, 680 Hz, 690 Hz, 700 Hz, 710 Hz, 720 Hz, 730 Hz, 740 Hz, 750 Hz, 760 Hz, 770 Hz, 780 Hz, 790 Hz or 800 Hz, but is not limited to the listed values, and other values ​​not listed within the range are also applicable.

[0033] Preferably, the average current density in the deamination is 10-20A, for example, it can be 10A, 11A, 12A, 13A, 14A, 15A, 16A, 17A, 18A, 19A or 20A, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0034] Preferably, the deamination time is 4-6h, for example, it can be 4h, 4.1h, 4.2h, 4.3h, 4.4h, 4.5h, 4.6h, 4.7h, 4.8h, 4.9h, 5h, 5.1h, 5.2h, 5.3h, 5.4h, 5.5h, 5.6h, 5.7h, 5.8h, 5.9h or 6h, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0035] Preferably, the pH value of the material in the bipolar membrane treatment is 3-8, for example, it can be 3, 3.2, 3.4, 3.6, 3.8, 4, 4.2, 4.4, 4.6, 4.8, 5, 5.2, 5.4, 5.6, 5.8, 6, 6.2, 6.4, 6.6, 6.8, 7, 7.2, 7.4, 7.6, 7.8 or 8, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0036] As a preferred technical solution of the present invention, the acid etching solution comprises: 110-120 g / L copper, 100-150 g / L chlorine, and 8-10 g / L sodium.

[0037] In the present invention, the mass concentration of copper in the acidic etching solution is 110-120 g / L, for example, it can be 110 g / L, 111 g / L, 112 g / L, 113 g / L, 114 g / L, 115 g / L, 116 g / L, 117 g / L, 118 g / L, 119 g / L or 120 g / L, but is not limited to the listed values, and other unlisted values ​​within the range are equally applicable.

[0038] In the present invention, the mass concentration of chlorine in the acidic etching solution is 100-150 g / L, for example, it can be 100 g / L, 105 g / L, 110 g / L, 115 g / L, 120 g / L, 125 g / L, 130 g / L, 135 g / L, 140 g / L, 145 g / L or 150 g / L, but is not limited to the listed values, and other unlisted values ​​within the range are equally applicable.

[0039] In the present invention, the mass concentration of sodium in the acidic etching solution is 8-10 g / L, for example, it can be 8 g / L, 8.2 g / L, 8.4 g / L, 8.6 g / L, 8.8 g / L, 9 g / L, 9.2 g / L, 9.4 g / L, 9.6 g / L, 9.8 g / L or 10 g / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0040] Preferably, the alkaline etching solution comprises: 110-120 g / L copper, 80-120 g / L chlorine, 100-120 g / L ammonia nitrogen, and 3-4 g / L sodium.

[0041] In the present invention, the mass concentration of copper in the alkaline etching solution is 110-120 g / L, for example, it can be 110 g / L, 111 g / L, 112 g / L, 113 g / L, 114 g / L, 115 g / L, 116 g / L, 117 g / L, 118 g / L, 119 g / L or 120 g / L, but is not limited to the listed values, and other unlisted values ​​within the range are equally applicable.

[0042] In the present invention, the mass concentration of chlorine in the alkaline etching solution is 80-120 g / L, for example, it can be 80 g / L, 85 g / L, 90 g / L, 95 g / L, 100 g / L, 105 g / L, 110 g / L, 115 g / L or 120 g / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0043] In the present invention, the mass concentration of ammonia nitrogen in the alkaline etching solution is 100-120 g / L, for example, it can be 100 g / L, 102 g / L, 104 g / L, 106 g / L, 108 g / L, 110 g / L, 112 g / L, 114 g / L, 116 g / L, 118 g / L or 120 g / L, but is not limited to the listed values, and other unlisted values ​​within the range are equally applicable.

[0044] In the present invention, the mass concentration of sodium in the alkaline etching solution is 3-4 g / L, for example, it can be 3 g / L, 3.1 g / L, 3.2 g / L, 3.3 g / L, 3.4 g / L, 3.5 g / L, 3.6 g / L, 3.7 g / L, 3.8 g / L, 3.9 g / L or 4 g / L, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0045] As a preferred technical solution of the present invention, the comprehensive utilization method comprises:

[0046] The acidic etching solution and the alkaline etching solution are mixed, and then an auxiliary agent is added, and then heat preservation treatment and solid-liquid separation are performed in sequence to obtain basic copper chloride;

[0047] The acidic etching solution includes: 110-120 g / L copper, 100-150 g / L chlorine, 8-10 g / L sodium; the alkaline etching solution includes: 110-120 g / L copper, 80-120 g / L chlorine, 100-120 g / L ammonia nitrogen, 3-4 g / L sodium;

[0048] The acidic etching solution is heated and stirred before mixing; the heating and stirring temperature is 50-60°C; the heating and stirring time is 20-30min; the end point of the mixing is when the pH value of the material is 6-7;

[0049] The auxiliary agent includes amino acid and hexadecyltrimethylammonium chloride; the mass ratio of amino acid to hexadecyltrimethylammonium chloride in the auxiliary agent is (1.5-2):1; the mass concentration of the auxiliary agent is 0.5-1%; the amount of the auxiliary agent added is 0.2-0.5% of the volume of the material obtained after mixing; the addition rate of the auxiliary agent is 5-10L / min; the temperature of the heat preservation treatment is 70-80°C; the heat preservation treatment time is 1-2h;

[0050] The temperature of the material in the solid-liquid separation is 40-50°C; the basic copper chloride obtained by the solid-liquid separation is washed; the solid-liquid ratio g / mL in the washing is 1:(1.5-2); the washing time is 1-2h; the washing water obtained by the washing and the filtrate obtained in the solid-liquid separation are mixed to obtain a liquid to be treated; the liquid to be treated is deaminated to obtain a deaminated liquid, and then the deaminated liquid is treated with a bipolar membrane to obtain an acid solution and an alkaline solution, which are returned to the preparation process for secondary utilization as a pH adjuster; the pH value of the material in the deammoniation is 9-10; the deammoniation is carried out by pulse electrolysis, the anode includes a graphite electrode, and the cathode includes a stainless steel electrode; the frequency of the pulse in the deammoniation is 600-800Hz; the average current density in the deammoniation is 10-20A; the deammoniation time is 4-6h; the pH value of the material in the bipolar membrane treatment is 3-8.

[0051] In the present invention, the amino acid can be glycine, alanine, valine, leucine, isoleucine, etc.

[0052] Compared with the prior art solutions, the present invention has the following beneficial effects:

[0053] (1) The present invention utilizes acid and alkaline etching solutions in a coordinated manner to neutralize copper deposition, thereby avoiding the problem of consuming a large amount of alkali when the etching solution is traditionally neutralized to recover copper, thereby greatly reducing the disposal cost.

[0054] (2) Based on the problem that copper still remains in the filtrate during the conventional synergistic neutralization of acid and alkali etching solutions, which affects the subsequent filtrate treatment, the present invention introduces glycine / hexadecyltrimethylammonium chloride auxiliary agents in a steady flow after the formation of basic copper chloride according to the reaction characteristics of the acid and alkali etching solutions. On the one hand, the coordination binding force between glycine and copper ions can be used to achieve complete conversion and precipitation of copper ions and to encapsulate them in basic copper chloride. On the other hand, the synergistic modification function of glycine and hexadecyltrimethylammonium chloride is used to make the synthesized basic copper chloride powder particles uniformly distributed and fine without mechanical impurities attached, and also have a special rhombus-shaped morphology. Finally, a basic copper chloride by-product with high quality and excellent performance can be obtained, and the purity of the obtained basic copper chloride is ≥98.9%.

[0055] (3) For the treatment of tail water, the present invention utilizes the sodium chloride component in the tail water, introduces pulse electrolysis, oxidizes free ammonia into nitrogen gas, and directly volatilizes and removes it from the tail water (Cl - Oxidized to Cl at the anode 2 , then converted into HClO, and then the free ammonia is oxidized into nitrogen, that is, 3HClO+2NH 3 =N 2 ↑+3HCl+3H 2 O). Compared with the traditional stripping of ammonia nitrogen, the present invention uses a pulse power supply instead of a traditional DC power supply, applies a pulse signal, and causes the reaction occurring on the electrode to be intermittent, which is more conducive to the diffusion of free ammonia molecules and accelerates the conversion and deamination process, thereby significantly optimizing the processing efficiency and energy consumption, and the deammoniation water can be finally recovered by bipolar membrane treatment to obtain high-quality byproducts, which can be directly reused in the process of the present invention.

[0056] (4) The present invention proposes a method for the coordinated recycling of acid and alkaline etching solutions. The overall process is simple and the treatment environment is relatively mild. It avoids the shortcomings of the existing treatment process to a large extent and can be implemented under normal conditions. At the same time, no secondary waste and secondary wastewater are generated during the process. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 A comprehensive utilization method of etching liquid provided in an embodiment of the present invention;

[0058] Figure 2 is a SEM photograph of basic copper chloride obtained in Example 1 of the present invention;

[0059] Figure 3 is a SEM photograph of basic cupric chloride obtained in Example 7 of the present invention;

[0060] Figure 4 This is a SEM photograph of basic cupric chloride obtained in Example 8 of the present invention.

[0061] The present invention is further described in detail below. However, the following examples are only simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims. DETAILED DESCRIPTION

[0062] To better illustrate the present invention and facilitate understanding of the technical solution of the present invention, typical but non-limiting embodiments of the present invention are as follows:

[0063] like Figure 1As shown in the figure, after the acidic etching solution and the alkaline etching solution are mixed, an auxiliary agent is added to react, and then basic copper chloride is obtained by solid-liquid separation. The washing liquid and the filtrate obtained by washing the basic copper chloride are mixed, and the pH value is adjusted, and pulse electrolysis is performed to deaminate to obtain a deaminated liquid. The deaminated liquid is treated with a bipolar membrane to obtain acid and alkali, which can be returned to the treatment process for pH adjustment.

[0064] The specific implementation process is as follows:

[0065] Example 1

[0066] This embodiment provides a comprehensive utilization method of etching solution, the process is as follows:

[0067] Take 1m 3 Acidic etching solution (copper 115g / L, chlorine 120g / L, sodium 9g / L) was heated and stirred at 50°C for 20min, and then alkaline etching solution (copper 115g / L, chlorine 100g / L, ammonia nitrogen 110g / L, sodium 3.5g / L) was gradually and slowly added thereto to adjust and maintain pH = 6; an auxiliary agent was added to the reaction material at a rate of 5L / min, according to 0.2% of the total volume of the mixed material, and the auxiliary agent was glycine and hexadecyltrimethylammonium chloride in a mass ratio of 1 .5:1, continue to add alkaline etching solution to adjust the stable pH to 6, then heat to 70°C and keep stirring for 1 hour at constant temperature, then cool to 40°C and filter to separate the crude basic cupric chloride and filtrate (copper content 2.6ppm); at a solid-liquid mass ratio of g / mL1:1.5, the crude product is pulped and washed for 1 hour, and then filtered to separate the purified basic cupric chloride (purity 99.2%, chlorine content 0.016%, particle size 60 mesh).

[0068] The washing water and the filtrate are adjusted to pH = 9 with liquid alkali, and placed in pulse electrolysis with a graphite plate as an anode and stainless steel as a cathode. The pulse frequency is controlled to 600 Hz and the average current density is 10A. After 4 hours of treatment, the free ammonia is removed and converted into nitrogen molecules; the deammoniation liquid is then adjusted to pH = 3 with hydrochloric acid, and then treated by bipolar membrane electrodialysis, and finally dilute hydrochloric acid (mass concentration 12%, recovery rate 97.8%) and dilute liquid alkali (mass concentration 8%, recovery rate 98.5%) can be obtained, both of which can be reused in the above process.

[0069] Figure 2 The figure is a schematic diagram of the morphology of the basic cupric chloride recovered in the present invention. It can be seen from the figure that the basic cupric chloride recovered is in a rhombus shape, is evenly staggered, and has a smooth surface without mechanical impurities attached.

[0070] Example 2

[0071] This embodiment provides a comprehensive utilization method of etching solution, the process is as follows:

[0072] Take 1.5m 3 Acidic etching solution (copper 110g / L, chlorine 150g / L, sodium 10g / L); heated and stirred at 55°C for 25min, then gradually and slowly added alkaline etching solution (copper 120g / L, chlorine 80g / L, ammonia nitrogen 120g / L, sodium 3g / L) to adjust and maintain pH = 6.5; add auxiliary agent to the reaction material at a rate of 8L / min, according to 0.4% of the total amount of the mixed material, and the auxiliary agent is glycine and hexadecyltrimethylammonium chloride in a mass ratio of 1.8:1 To the pre-prepared 0.75% aqueous solution, alkaline etching solution was continuously added to adjust the stable pH to 6.5, and then the temperature was raised to 75°C and the reaction was continued with constant stirring for 1.5 hours, and then the crude basic cupric chloride and the filtrate (copper content 3.04 ppm) were obtained after cooling to 45°C. The crude product was pulped and washed for 1.5 hours at a solid-liquid mass ratio of 1:1.8, and then filtered and separated to obtain purified basic cupric chloride (purity 99.6%, chlorine content 0.02%, particle size 80 mesh).

[0073] The washing water and the filtrate are adjusted to pH = 9.5 with liquid alkali, and placed in pulse electrolysis with a graphite plate as an anode and stainless steel as a cathode. The pulse frequency is controlled to 700 Hz and the average current density is controlled to 15 A. After 5 hours of treatment, the free ammonia is removed and converted into nitrogen molecules; the deammoniation liquid is then adjusted to pH = 6 with hydrochloric acid, and then treated by bipolar membrane electrodialysis, and finally dilute hydrochloric acid (mass concentration 10%, recovery rate 98.6%) and dilute liquid alkali (mass concentration 9%, recovery rate 99.2%) can be obtained, both of which can be reused in the above process.

[0074] Example 3

[0075] This embodiment provides a comprehensive utilization method of etching solution, the process is as follows:

[0076] Take 2m 3Acidic etching solution (copper 120g / L, chlorine 100g / L, sodium 8g / L) was heated and stirred at 60°C for 30min, and then alkaline etching solution (copper 110g / L, chlorine 120g / L, ammonia nitrogen 100g / L, sodium 4g / L) was gradually and slowly added thereto to adjust and maintain pH = 7; an auxiliary agent was added to the reaction material at a rate of 10L / min, which was 0.5% of the total amount of the mixed material and glycine and hexadecyltrimethylammonium chloride in a mass ratio of 2 :1 A pre-prepared 1% aqueous solution was continuously added with alkaline etching solution to adjust the stable pH to 7, and then the temperature was raised to 80°C and the reaction was continued with constant stirring for 2 hours, and then the crude basic cupric chloride and the filtrate (copper content 1.48 ppm) were obtained after cooling to 50°C. The crude product was pulped and washed for 2 hours at a solid-liquid mass ratio of g / mL of 1:2, and then filtered and separated to obtain purified pure basic cupric chloride (purity 98.9%, chlorine content 0.012%, particle size 95 mesh).

[0077] The washing water and the filtrate are adjusted to pH=10 with liquid alkali, and placed in pulse electrolysis with a graphite plate as an anode and stainless steel as a cathode. The pulse frequency is controlled to 800 Hz and the average current density is controlled to 20 A. After 6 hours of treatment, the free ammonia is removed and converted into nitrogen molecules; the deammoniation liquid is then adjusted to pH=8 with hydrochloric acid, and then treated by bipolar membrane electrodialysis, and finally dilute hydrochloric acid (mass concentration 14%, recovery rate 99%) and dilute liquid alkali (mass concentration 9.5%, recovery rate 98%) can be obtained, both of which can be reused in the above process.

[0078] Example 4

[0079] The only difference from Example 1 is that the mass ratio of glycine to hexadecyltrimethylammonium chloride in the auxiliary agent is 1:1.

[0080] The obtained basic cupric chloride has poor dispersibility, is difficult to disperse in water, and adheres to the wall. The purity of the basic cupric chloride is 88.6%, and the chlorine content is 0.114%.

[0081] Example 5

[0082] The only difference from Example 1 is that the mass ratio of glycine to hexadecyltrimethylammonium chloride in the auxiliary agent is 3:1.

[0083] The obtained basic cupric chloride has poor dispersibility and is sticky. It is easy to adhere to the wall when dispersed. The purity of the basic cupric chloride is 89.2%, and the chlorine content is 0.114%.

[0084] Example 6

[0085] The only difference from Example 1 is that the amount of the additive added is 1% of the volume of the material obtained after mixing.

[0086] The obtained basic cupric chloride has significant viscosity and is difficult to disperse in water. The purity of the basic cupric chloride is 91.6% and the chlorine content is 0.064%.

[0087] Example 7

[0088] The only difference from Example 1 is that the auxiliary agent is added all at once instead of controlling the addition rate.

[0089] The obtained basic copper chloride is a light green solid. After air drying, its fluidity is very poor. The overall particle size distribution is different and it is an irregular flake aggregate. Figure 3 As shown, the purity of basic copper chloride is 92.8% and the chlorine content is 0.035%.

[0090] Example 8

[0091] The only difference from Example 1 is that hexadecyltrimethylammonium chloride is replaced by an equal amount of sodium dodecylbenzenesulfonate.

[0092] The obtained basic copper chloride has a good overall particle distribution, but is an irregular long flake aggregate, such as Figure 4 As shown, the basic copper chloride with a rhombus structure of the present invention cannot be obtained, the purity of the basic copper chloride is 95.2%, and the chlorine content is 0.022%.

[0093] Example 9

[0094] The only difference from Example 1 is that hexadecyltrimethylammonium chloride is replaced by an equal amount of benzalkonium chloride. The obtained basic cupric chloride is a green powder with a fair overall particle distribution. The whole is an irregular sphere and is composed of a large number of irregular sheet-like strips stacked together. The purity of the basic cupric chloride is 91.5% and the chlorine content is 0.062%.

[0095] Example 10

[0096] The only difference from Example 1 is that glycine is replaced by an equal amount of acetic acid. The obtained basic cupric chloride powder has significant viscosity, and the overall particle distribution is of different sizes. The purity of the basic cupric chloride is 93.2%, and the chlorine content is 0.045%.

[0097] It can be seen from the results of the above examples that the present invention achieves efficient recovery of copper elements in the etching solution by using an auxiliary agent of a specific composition, and the obtained basic copper chloride product has a specific rhombus structure, thereby achieving the preparation of a specific basic copper chloride.

[0098] It is stated that the present invention illustrates the detailed structural features of the present invention through the above embodiments, but the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must rely on the above detailed structural features to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the components selected by the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0099] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0100] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0101] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A comprehensive utilization method of etching solution, characterized in that: The comprehensive utilization method comprises: The acidic etching solution and the alkaline etching solution are mixed, and then an auxiliary agent is added, and then heat preservation treatment and solid-liquid separation are performed in sequence to obtain basic copper chloride with a rhombus structure; The amount of the additive added is 0.2-0.5% of the volume of the material obtained after mixing; The auxiliary agent includes glycine and hexadecyltrimethylammonium chloride in a mass ratio of (1.5-2):1; The acidic etching solution includes: 110-120 g / L copper, 100-150 g / L chlorine, 8-10 g / L sodium; the alkaline etching solution includes: 110-120 g / L copper, 80-120 g / L chlorine, 100-120 g / L ammonia nitrogen, 3-4 g / L sodium; The acidic etching solution is heated and stirred before mixing; the heating and stirring temperature is 50-60°C; the heating and stirring time is 20-30min; the end point of the mixing is when the pH value of the material is 6-7; The mass concentration of the auxiliary agent is 0.5-1%; the adding rate of the auxiliary agent is 5-10 L / min; the temperature of the heat preservation treatment is 70-80° C.; and the time of the heat preservation treatment is 1-2 h.

2. The comprehensive utilization method according to claim 1, characterized in that: The temperature of the material during the solid-liquid separation is 40-50°C.

3. The comprehensive utilization method according to claim 1, characterized in that: The basic copper chloride obtained by the solid-liquid separation is washed.

4. The comprehensive utilization method according to claim 3, characterized in that: The solid-to-liquid ratio g / mL in the washing is 1:(1.5-2).

5. The comprehensive utilization method according to claim 3, characterized in that: The washing time is 1-2h.

6. The comprehensive utilization method according to claim 3, characterized in that: The washing water obtained from the washing and the filtrate obtained from the solid-liquid separation are mixed to obtain a liquid to be treated.

7. The comprehensive utilization method according to claim 6, characterized in that: The liquid to be treated is deaminated to obtain a deaminated liquid, and then the deaminated liquid is treated with a bipolar membrane to obtain an acid solution and an alkaline solution, which are returned to the preparation process for secondary utilization as a pH adjuster.

8. The comprehensive utilization method according to claim 7, characterized in that: The pH value of the material in the deamination process is 9-10.

9. The comprehensive utilization method according to claim 7, characterized in that: The deamination is carried out by pulse electrolysis, the anode comprises a graphite electrode, and the cathode comprises a stainless steel electrode.

10. The comprehensive utilization method according to claim 9, characterized in that: The frequency of the pulses in the deamination is 600-800 Hz.

11. The comprehensive utilization method according to claim 7, characterized in that: The deamination time is 4-6h.

12. The comprehensive utilization method according to claim 7, characterized in that: The pH value of the material in the bipolar membrane treatment is 3-8.

13. The comprehensive utilization method according to claim 1, characterized in that: The comprehensive utilization method comprises: The temperature of the material in the solid-liquid separation is 40-50°C; the basic copper chloride obtained by the solid-liquid separation is washed; the solid-liquid ratio g / mL in the washing is 1:(1.5-2); the washing time is 1-2h; the washing water obtained by the washing and the filtrate obtained in the solid-liquid separation are mixed to obtain a liquid to be treated; the liquid to be treated is deaminated to obtain a deaminated liquid, and then the deaminated liquid is treated with a bipolar membrane to obtain an acid solution and an alkaline solution, which are returned to the preparation process for secondary utilization as a pH adjuster; the pH value of the material in the deammoniation is 9-10; the deammoniation is carried out by pulse electrolysis, the anode includes a graphite electrode, and the cathode includes a stainless steel electrode; the frequency of the pulse in the deammoniation is 600-800Hz; the deammoniation time is 4-6h; the pH value of the material in the bipolar membrane treatment is 3-8.

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