Method and apparatus for dissolving metallic copper in acid copper plating bath

Abstract

Disclosed in the present invention are a method and apparatus for dissolving metallic copper in an acid copper plating bath. The method comprises: step 1, using an electrocatalytic gas-liquid reaction tank connected to an electroplating tank via piping to take, from the electroplating tank that is in electroplating operation, a portion of the copper plating bath and divert same into the electrocatalytic gas-liquid reaction tank for electrocatalytic oxidation; step 2, turning on an electrocatalytic power supply, and feeding an oxidizing gas into a gas-liquid mixer in the electrocatalytic gas-liquid reaction tank; step 3, controlling the entire reaction process of the reaction liquid in the electrocatalytic gas-liquid reaction tank by using a cascade control system, wherein with reference to input parameters from a primary control system and via an inter-level transfer function relationship, a controlled target of a final-stage control system is controlled, so that no copper is electrodeposited on an electrocatalytic cathode during the reaction, or the rate of copper electrodeposition on the cathode is maintained within a process-allowable range; and step 4, returning the copper plating bath having undergone metallic copper dissolution treatment in the electrocatalytic gas-liquid reaction tank to the electroplating tank for continued electroplating.

Description

A method and apparatus for dissolving metallic copper in an acidic copper plating solution. Technical Field

[0001] This invention belongs to the technical field of bright electroplating process of acidic copper sulfate, specifically relating to a method and apparatus for dissolving metallic copper in an acidic copper plating solution. Background Technology

[0002] The existing bright electroplating process for acidic copper sulfate involves using an electroplating tank filled with an acidic copper sulfate plating solution (hereinafter referred to as the copper plating solution). The electroplating anode and cathode (i.e., the cathode workpiece) connected to the electroplating power source are immersed in the copper plating solution for electroplating, allowing copper to be electroplated onto the cathode workpiece. The copper plating solution mainly consists of copper sulfate and sulfuric acid, and contains small amounts of chloride ions and electroplating additives. Depending on the material of the electroplating anode, the existing electroplating process is specifically divided into soluble anode electroplating and insoluble anode electroplating. These two types of electroplating processes correspond to different copper source replenishment methods for the copper plating solution. In copper plating operations, multiple quality parameters of the plated parts need to be considered, such as the adhesion of the plating layer, the roughness of the plating layer, and the uniformity of the plating layer. A common quality problem is that during the electroplating process, a cathode workpiece may fall off, causing an excessively high electroplating current density in a certain area of ​​other cathode workpieces, resulting in a loose and rough plating layer, or even copper powder dispersed into the copper plating solution. In addition, various other factors during electroplating can lead to the formation of cuprous oxide (Cu₂O), cuprous sulfate (Cu₂SO₄), and cuprous chloride (CuCl) in the copper plating solution. Since cuprous oxide and cuprous sulfate are extremely unstable in acidic media, they readily undergo disproportionation reactions to rapidly generate copper sulfate and copper powder. Copper powder and cuprous chloride are sparingly soluble in the absence of an oxidizing agent. The presence of a certain amount of copper powder and cuprous chloride in the copper plating solution can create an undesirable, rough copper layer on the surface of the cathode, thus affecting the quality of the plated part.

[0003] The following section explains the copper source replenishment mode of the copper plating solution and the reasons for the generation of monovalent copper ions during the electroplating process, based on different electroplating processes.

[0004] I. Soluble anode electroplating process, which uses phosphorus copper as the soluble anode. During electroplating, phosphorus copper balls are placed in a titanium basket wrapped with a filter bag for electrochemical oxidation and dissolution, continuously replenishing the copper ions in the plating solution and resulting in a better coating on the cathode. However, the dissolved phosphorus copper balls need to be replaced when their volume decreases to a certain extent, as they cannot be fully utilized. As electroplating progresses, the surface area of ​​the phosphorus copper anode changes continuously, leading to uneven distribution of the electric field lines, which degrades the electroplating quality and generates a large amount of difficult-to-treat phosphorus-containing wastewater.

[0005] During the electroplating dissolution process, the phosphor bronze anode produces cuprous oxide (Cu₂O). The cuprous oxide then undergoes a disproportionation reaction in sulfuric acid medium: Cu₂O + H₂SO₄ → CuSO₄ + H₂O + Cu

[0006] In addition, in the soluble anodic electroplating process, the copper plating solution also produces monovalent copper ion compounds in the following two places.

[0007] Copper dissolution process at the anode of phosphorus copper: Cu-e - →Cu + Cu + -e - →Cu 2+

[0008] Electroplating of copper at the cathode: Cu 2+ +e - →Cu + Cu + +e - →Cu

[0009] II. Insoluble anodic electroplating process: This process uses an insoluble anode and a cathode to form an electrode pair for electroplating, allowing copper to be electroplated onto the cathode. The copper source for the plating solution is introduced from outside the electroplating system. Because the insoluble anodic electroplating process offers higher plating quality and a larger operating current compared to the soluble phosphorus copper anodic electroplating process, its improvements in quality and yield have been widely recognized and promoted.

[0010] Common insoluble anodic electroplating processes are further divided into two types based on whether the copper plating solution contains iron ions: iron-free insoluble anodic electroplating process and iron-containing insoluble anodic electroplating process.

[0011] In iron-free insoluble anode electroplating processes, the insoluble anode only serves to conduct electricity and improve current density distribution during electroplating. Oxygen is released from the insoluble anode during the process. This process replenishes the copper source by directly adding dissolved copper oxide to the copper plating solution, thus maintaining the copper ion concentration set by the process for electroplating production.

[0012] In the iron-containing insoluble anode electroplating process, the insoluble anode, besides its functions of conductivity and improving current density distribution, also plays a crucial role in the electrochemical oxidation of ferrous ions in the iron-containing copper plating solution, regenerating them into ferric ions. Therefore, during the electroplating process, the insoluble anode produces little or no oxygen evolution. In this process, the copper plating solution containing ferric ions in the electroplating tank is diverted to a copper dissolving tank to react with added metallic copper, thus replenishing the copper source. The chemical reaction for copper dissolution is shown below: 2Fe 3+ +Cu→2Fe 2+ +Cu 2+

[0013] The copper plating solution still contains a small amount of ferric ions after the copper source is replenished. This copper plating solution with a high copper ion concentration containing ferric ions is returned to the electroplating tank for electroplating reaction according to process requirements.

[0014] Regarding the reason for the formation of monovalent copper ion compounds, both insoluble anodic electroplating processes generate monovalent copper ion compounds during the cathode electroplating process. The electrochemical reaction at the cathode is as follows: Cu 2+ +e - →Cu + Cu + +e - →Cu

[0015] To address the impact of monovalent copper ions and their disproportionation reactions producing copper powder on electroplating quality, existing technologies involve adding hydrogen peroxide or aeration to the copper plating solution in soluble anodic electroplating and iron-free insoluble anodic electroplating processes. This is combined with liquid circulation in the electroplating tank to oxidize and reduce the copper powder continuously generated by the disproportionation reaction. However, adding hydrogen peroxide dilutes the copper plating solution, affecting electroplating production, while aeration has a slow oxidation rate that is difficult to meet production requirements.

[0016] For iron-containing insoluble anodic electroplating processes, although the ferric ions in the copper plating solution can oxidize the produced monovalent copper ions to divalent copper ions, excessive ferric ions in the plating solution can corrode the cathode workpiece, while insufficient ferric ion concentration can limit the dissolution rate of metallic copper used as a copper source. Therefore, iron-containing insoluble anodic electroplating processes require strict control of the ferric ion concentration margin in the copper plating solution. Furthermore, the amount of monovalent copper ions produced in the copper plating solution per unit time varies with the electroplating current. Therefore, in insoluble anodic electroplating processes where the iron concentration in the copper plating solution is constant, the amount of ferric ions regenerated by anodic electrolysis is difficult to match in real time with the continuously generated monovalent copper ion compounds and the copper powder produced by their disproportionation reaction. Thus, iron-containing insoluble anodic electroplating processes suffer from the problem of timely elimination of the continuously generated monovalent copper ion compounds and the copper powder produced by disproportionation reaction due to the difficulty of ferric ions in the copper plating solution effectively.

[0017] As can be seen from the above introduction, the copper source replenishment mode of the iron-free insoluble anodic electroplating process is to add copper oxide powder into the copper plating solution to dissolve and generate copper sulfate; while the copper source replenishment mode of the iron-containing insoluble anodic electroplating process mainly uses insoluble anodes to replenish the Fe in the copper plating solution. 2+ Oxidation and regeneration to Fe 3+ Then through Fe 3+ Oxidation dissolves metallic copper to form copper sulfate, Fe 3+ The ions were reduced to Fe. 2+Because copper oxide powder is an expensive material, the iron-free insoluble anodic electroplating process faces cost issues in terms of cost reduction and efficiency improvement; while the iron-containing insoluble anodic electroplating process utilizes the Fe in the copper plating solution. 3+ To produce copper sulfate by corroding and dissolving metallic copper, Fe was encountered. 3+ The problem of corrosion of cathode-plated parts affecting electroplating quality.

[0018] In insoluble anodic electroplating processes, existing technologies also employ an electrolytic copper dissolution tank with partitions to electrochemically oxidize and dissolve the copper anode, thus replenishing the copper source for the plating solution. In this copper source replenishment mode, to achieve copper dissolution during electrolysis, the process requires that the electrolytic cathode not deposit copper; instead, the electrochemical reaction necessitates the deposition of hydrogen gas from the cathode to complete the copper dissolution reaction. Therefore, this copper source replenishment mode presents a hazard due to hydrogen gas deposition, potentially leading to production accidents. Consequently, this electrolytic copper dissolution copper source replenishment process requires further improvement.

[0019] Therefore, among various copper source replenishment methods for copper plating solutions, the soluble phosphorus copper anolyte electroplating process generates monovalent copper ions more readily during electroplating than the insoluble anolyte electroplating process, and also produces more copper powder from the disproportionation reaction. The copper powder generated by the disproportionation reaction is the same type of metallic substance as the copper added from outside the electroplating system, and needs to be dissolved and reused in the electroplating production.

[0020] Because the copper powder present in the copper plating solution of the existing acidic copper sulfate electroplating process is the main problem affecting the electroplating quality, there is an urgent need for a new copper dissolving process on the market that can solve the problem of the continuous production of monovalent copper ions in the copper plating solution and the copper powder produced by the disproportionation reaction, which affects the electroplating quality; and solve the problem of copper source replenishment in the existing insoluble anodic electroplating process, so as to achieve a qualitative leap in the electroplating copper process and improve the process indicators of electroplating production in terms of safety, quality, efficiency, cost and pollution. Summary of the Invention

[0021] The first objective of this invention is to provide a method for dissolving metallic copper in an acidic copper plating solution, enabling the timely reduction of copper powder produced by the disproportionation reaction of cuprous chloride and monovalent copper ions in the plating solution during electroplating operations, based on the change in the amount generated, or achieving better copper dissolution performance, effectively improving the copper source replenishment process and enhancing electroplating quality. The second objective of this invention is to provide an apparatus for dissolving metallic copper in an acidic copper plating solution.

[0022] The first objective of this invention can be achieved through the following solutions.

[0023] A method for dissolving metallic copper in an acidic copper plating solution includes the following steps:

[0024] Step 1: Using an electrocatalytic gas-liquid reaction tank connected to the electroplating tank via a pipeline, a portion of the copper plating solution is taken from the electroplating tank undergoing electroplating and diverted into the electrocatalytic gas-liquid reaction tank for electrocatalytic oxidation; the electrocatalytic gas-liquid reaction tank includes an electrocatalytic anode, an electrocatalytic cathode, an electrocatalytic power supply, and a gas-liquid mixer, wherein the positive and negative terminals of the electrocatalytic power supply are connected to the electrocatalytic anode and the electrocatalytic cathode, respectively.

[0025] Step 2: Turn on the electrocatalytic power supply and input oxidizing gas into the gas-liquid mixer in the electrocatalytic gas-liquid reaction tank. The oxidizing gas then undergoes an electrochemical reaction with the electrocatalytic cathode under electrocatalysis, and simultaneously undergoes an oxidative chemical reaction with cuprous chloride and / or metallic copper in the copper plating solution under acidic medium. In addition, the electrocatalytic anode also undergoes a contact-type electrochemical oxidation and dissolution reaction with cuprous chloride and / or metallic copper in the copper plating solution.

[0026] Step 3: The entire reaction process of the reaction liquid in the electrocatalytic gas-liquid reaction tank is controlled by a cascade control system. The primary control system uses reference input parameters and inter-level transfer functions to regulate the controlled target of the final control system. Specifically, the value or change of the electroplating current, combined with the copper source replenishment mode of the copper plating solution selected in the electrocatalytic gas-liquid reaction tank, serves as the reference input parameter for the primary control system. The primary output controlled parameter, the voltage or current value output by the electrocatalytic power supply, is obtained according to the primary transfer function. This primary output controlled parameter is then used as the input parameter for the final control system. The amount of oxidizing gas introduced into the final control system is regulated using the transfer function of the final control system. This cascade control method ensures that the electrocatalytic cathode does not electrodeposit copper during the reaction process, or that the rate of copper deposition at the cathode remains within the allowable range of the process.

[0027] Step 4: The copper plating solution, after undergoing electrocatalytic oxidation and dissolution of metallic copper in the electrocatalytic gas-liquid reaction tank, is returned to the electroplating tank according to process requirements to continue participating in the electroplating reaction.

[0028] The metallic copper in the copper plating solution mentioned in step 2 is copper powder produced by the disproportionation reaction of monovalent copper ion compounds in the copper plating solution and / or metallic copper from outside the electroplating tank. The metallic copper from outside the electroplating tank is preferably a soluble metallic copper anode used as an electrocatalytic anode, which can replenish the copper source of the copper plating solution after dissolution.

[0029] When introducing metallic copper from outside the electroplating tank into the electrocatalytic gas-liquid reaction tank as a copper source to replenish the copper plating solution, the copper ion concentration of the copper plating solution that has already undergone oxidation treatment in the electrocatalytic gas-liquid reaction tank should be higher than or equal to the copper ion concentration set by the copper plating solution used in the electroplating tank.

[0030] In step 1, the copper plating solution in the electroplating tank is diverted to the electrocatalytic gas-liquid reaction tank in an intermittent or continuous manner, based on at least one parameter that affects the concentration of divalent copper ions and / or the total amount of cuprous chloride and copper powder in the electroplating tank during the electroplating process. Preferably, the parameter value of the change in the concentration of divalent copper ions in the copper plating solution in the electroplating tank is used as the controlled object for extraction. Specifically, the parameters that cause and reflect the change in the concentration of divalent copper ions in the copper plating solution in the electroplating tank during operation include the electroplating time, electroplating current density, solution level, and the color, acidity, and redox potential of the copper plating solution.

[0031] In step 2, the oxidizing gas is ozone and / or oxygen and / or air.

[0032] In step 2, during the electrocatalytic oxidation process, the standard electrode potentials of various oxidizing gases are all higher than those of Cu. 2+ The oxidizing gas preferentially reacts with the electrocatalytic cathode, making it difficult for copper ions in the copper plating solution to be reduced and deposited through electrochemical reaction. Therefore, the electrochemical reaction formula of the electrocatalytic cathode is as follows: 4H + +O2+4e - →2H₂O 6H + +O3+6e - →3H2O

[0033] Meanwhile, when the main function of the electrocatalytic anode is to reduce cuprous chloride or copper powder produced by the disproportionation reaction in the copper plating solution, the electrochemical reactions that mainly occur at the electrocatalytic anode with cuprous chloride and / or metallic copper powder are as follows: Cu-2e - →Cu 2+ Cu + -e - →Cu 2+ 4[OH] - -4e - →2H₂O + O₂

[0034] When the electrocatalytic anode also functions as an electrochemical oxidation dissolution source of metallic copper from outside the electroplating tank, the main electrochemical reaction occurring at the electrocatalytic anode is as follows: Cu - 2e - →Cu 2+ Cu + -e - →Cu 2+

[0035] Because the copper plating solution contains a large amount of sulfuric acid, the monovalent copper compounds and metallic copper mentioned above mainly combine with sulfuric acid to form copper sulfate CuSO4 during the copper dissolution reaction.

[0036] In addition, the oxidizing gas is mixed and introduced into the copper plating solution in the electrocatalytic gas-liquid reaction tank through a gas-liquid mixer. Under acidic medium, the oxidizing gas directly oxidizes the copper block, copper powder, and cuprous chloride: 3Cu + O3 + 3H2SO4 → 3CuSO4 + 3H2O; 2Cu + O2 + 2H2SO4 → 2CuSO4 + 2H2O; 6CuCl + O3 + 3H2SO4 → 3CuSO4 + 3CuCl2 + 3H2O; 4CuCl + O2 + 2H2SO4 → 2CuSO4 + 2CuCl2 + 2H2O.

[0037] When the copper plating solution contains iron ions, the following electrochemical reaction also occurs at the electrocatalytic anode: Fe 2+ +e - →Fe 3+ .

[0038] The oxidizing gases mixed into the copper plating solution in the electrocatalytic gas-liquid reaction tank via a gas-liquid mixer also affect Fe under acidic conditions. 2+ An oxidation reaction occurs to produce Fe. 3+ 6Fe 2+ +6H + +O3→6Fe 3+ +3H₂O; 4Fe 2+ +4H + +O2→4Fe 3+ +2H2O.

[0039] Meanwhile, ferric ions will also react chemically with monovalent copper ions and metallic copper powder in the copper plating solution: Fe 3+ +Cu + →Fe 2+ +Cu 2+ ; 2Fe 3+ +Cu→2Fe 2+ +Cu 2+ .

[0040] The method of this invention utilizes an electrochemical copper dissolution reaction that converts electrical energy into chemical energy, effectively solving the problems caused by hydrogen gas deposition at the electrolytic cathode and the production of cuprous chloride and copper powder from the disproportionation of monovalent copper ions in the copper plating solution during the electrochemical copper dissolution process. Furthermore, it can replenish the copper source for the plating solution. This invention utilizes the principle of oxidizing gas technology combined with a cascade control system to regulate the amount of oxidizing gas input to the final-stage control system through inter-level transfer function relationships. This avoids the highly hazardous, flammable, and explosive hydrogen gas deposition at the electrolytic cathode, saves raw materials for oxidizing gas production through system control, and effectively reduces the amount of cuprous chloride and disproportionated copper powder in the copper plating solution according to changes in their generation.

[0041] In step 3, the present invention requires, in terms of process, that the electrocatalytic anode electrolyzes and dissolves copper, and controls the electrocatalytic cathode to prevent copper deposition during the electrochemical reduction reaction, or to maintain the rate of copper deposition at the cathode within the allowable range of the process. The copper source replenishment mode for the copper plating solution in the electrocatalytic gas-liquid reaction tank is divided into two types: one is not to replenish the copper source, and the other is to use metallic copper from outside the electroplating system as the copper source for electrolytic dissolution. Therefore, the control system for the reaction process in the electrocatalytic gas-liquid reactor is set as a two-stage cascade open-loop control system. The primary control system uses the copper source replenishment mode of the copper plating solution in the electrocatalytic gas-liquid reactor as a reference input parameter, and the electroplating current value or its change in the electroplating tank as another reference input parameter. The primary output controlled parameter, i.e., the voltage or current value output by the electrocatalytic power supply, is obtained through the transfer function relationship of the primary control system. The final control system uses this primary output controlled parameter as the final stage input parameter and regulates the amount of oxidizing gas input to the final stage system through the transfer function relationship of the final stage control system. This achieves the goal of preventing copper electrodeposition at the electrocatalytic cathode or maintaining the rate of copper electrodeposition at the cathode within the allowable range of the process, and achieving the goal of efficient copper dissolution by reducing the emission of oxidizing gas and environmental pollution during the production process of the electrocatalytic gas-liquid reactor. Different structural details of the electrocatalytic gas-liquid reactor will result in different oxidation performance.

[0042] The electrocatalytic gas-liquid reaction tank of this invention is classified into two functional categories based on the electroplating current density or its variation and the copper source replenishment mode of the copper plating solution in the electrocatalytic gas-liquid reaction tank. The first function is: when the electrocatalytic anode is an insoluble anode, i.e., there is no metallic copper from outside the electroplating tank, the electrocatalytic gas-liquid reaction tank can reduce cuprous chloride and copper powder produced by the disproportionation reaction in the copper plating solution, and also oxidize and regenerate it when the electroplating solution contains ferrous ions. The second function is: when the electrocatalytic anode includes a soluble metallic copper anode, i.e., there is metallic copper from outside the electroplating tank, the electrocatalytic gas-liquid reaction tank, based on the first function, adds the function of dissolving metallic copper from outside the electroplating tank to provide a large amount of copper source replenishment to the copper plating solution. That is, it simultaneously utilizes the soluble metallic copper anode to perform the function of the insoluble anode in the first function, namely, electrolytically dissolving the cuprous chloride and copper powder in the copper plating solution through an electrochemical oxidation reaction caused by collision. Preferably, the electrocatalytic anode in the electrocatalytic gas-liquid reaction tank with the second function includes an insoluble anode assembly and a soluble metallic copper anode.

[0043] In the electrocatalytic gas-liquid reaction vessel of this invention, when only the first function described above is present, the voltage value output by the electrocatalytic power supply is used as the input parameter of the final-stage control system in the control system, and the input parameter value of the controlled target oxidizing gas is controlled through a transfer function relationship. For the electrocatalytic gas-liquid reaction vessel with the second function described above, the current value output by the electrocatalytic power supply is used as the input parameter of the final-stage control system in the control system, and the input parameter value of the controlled target oxidizing gas is controlled through its transfer function relationship.

[0044] When using an electrocatalytic gas-liquid reaction tank with only the first function described above, i.e., when only cuprous chloride in the copper plating solution needs to be oxidized and copper powder produced by disproportionation needs to be generated, the output voltage range of the electrocatalytic power supply is controlled to be 0.34–24V. This allows for the electrochemical oxidation and dissolution of the copper powder and cuprous chloride produced by the disproportionation reaction in the copper plating solution by contacting the electrocatalytic anode under a safe voltage that allows continuous human contact. When the copper plating solution contains iron ions, the output voltage range of the electrocatalytic power supply is selected to be 0.77–24V. Preferably, the output voltage of the electrocatalytic power supply is adjusted to the electrolytic decomposition voltage value or a positive deviation voltage value is added to its target electrolytic decomposition voltage value for electrolytic operation. This ensures that the copper plating solution can efficiently dissolve copper during electrolytic oxidation and reduces the electrochemical reaction that synthesizes chloroxylenoids (ClO·) in the electrolyte, thus preventing the destruction of additives. The electrolytic decomposition voltage value of the copper plating solution in the electrocatalytic gas-liquid reaction tank refers to the voltage difference applied between the anode and cathode of the electrocatalytic power supply when the output voltage is adjusted on-site, causing the insoluble anode to initially electrodeposit oxygen bubbles in the copper plating solution. This critical point is defined as the voltage output of the electrocatalytic power supply at which the copper plating solution begins to decompose. The positive deviation voltage value is the difference between the actual operating voltage value and the target electrolytic decomposition voltage value, ranging from 0 to the upper limit of the positive deviation. The upper limit refers to the voltage point at which the voltage output by the electrocatalytic power supply, when adjusted, causes the electrolyte in the electrocatalytic gas-liquid reaction tank to electrolyze and generate chloroxylenoids (ClO·), an oxidant that begins to cause significant damage to the additives in the copper plating solution. The difference between this voltage point and the electrolytic decomposition voltage value is the upper limit of the positive deviation. Using a voltage value that is the target electrolytic decomposition voltage plus a positive deviation for electrolysis operations satisfies the copper dissolution requirements of the process while avoiding significant damage to additives during electrolysis. Preferably, for iron-containing copper plating solutions, an electrocatalytic power supply with an output voltage of not less than 0.77V is selected to oxidize ferrous ions to ferric ions. The specific positive deviation voltage value added to the electrolytic decomposition voltage is determined based on the actual operating process conditions.

[0045] The electrolytic decomposition voltage value is related to various factors such as the structure of the electrocatalytic gas-liquid reaction tank, electrode material, distance between the two electrodes, electrode immersion energized area and structure, composition and concentration of copper plating solution, viscosity and temperature of copper plating solution reaction, etc. Therefore, the electrolytic decomposition voltage value obtained by combining electrocatalytic gas-liquid reaction tanks with different structures and different electrolytes will be different; under the premise that the structure of the electrolytic tank and the composition and concentration of the electrolyte remain unchanged, the electrolytic decomposition voltage will be a stable voltage value.

[0046] When using an electrocatalytic gas-liquid reaction tank with a second function, i.e., when replenishing the copper source of the copper plating solution with an electrocatalytic anode including a soluble metallic copper anode, the output current value of the electrocatalytic power supply is adjusted during the copper source replenishment process according to Faraday's law of electrolysis. This ensures that the electrochemical reaction of oxidizing and dissolving metallic copper mainly occurs on the electrocatalytic anode. The output current value of the electrocatalytic power supply is used as the input parameter of the final-stage control system in the control system to control the amount of oxidizing gas introduced at the final output target value, thereby achieving the process objective of dissolving metallic copper from outside the electroplating tank. The electrolytic efficiency of copper dissolution in this invention can reach 100%. In addition, the oxidizing gas assists in the copper dissolution reaction in the acidic copper plating solution medium, which can rapidly increase the copper ion concentration in the copper plating solution within the electrocatalytic gas-liquid reaction tank to the set value of the copper source replenishment process. Therefore, compared with the existing soluble phosphorus copper anode electroplating process, the copper dissolution efficiency and the utilization rate of soluble anode copper of the present invention are both higher than those of the existing soluble phosphorus copper anode electroplating process. This is because Cu3P exists and is distributed on the surface of the phosphorus copper ball, which has a high resistance and therefore low copper dissolution efficiency. In addition, the present invention can also avoid the cost of treating phosphorus-containing waste liquid.

[0047] The electrocatalytic oxidation capacity of the electrocatalytic gas-liquid reaction tank is determined by the output current or voltage of the electrocatalytic power supply. A higher output current or voltage results in a greater electrocatalytic oxidation capacity of the anode. A larger specific surface area of ​​the electrocatalytic cathode leads to better reaction with oxidizing gases. Meeting these two conditions strengthens the copper dissolution capacity of the electrocatalytic gas-liquid reaction tank. When using the electrocatalytic gas-liquid reaction tank to replenish the copper source in the insoluble anode electroplating process, the work done (kWh) by the electrocatalytic power supply during the entire electroplating process must be greater than or equal to the work done by the electroplating power supply. Because the process requires the copper dissolution rate of the second function to be greater than or equal to the rate of copper deposition in the electroplating tank, once the copper ion concentration in the electrolyte reaches the process requirements, the electrocatalytic power supply of the electrocatalytic gas-liquid reaction tank with the second function needs to be intermittently switched on and off, or its output current temporarily reduced according to process requirements, to balance the electroplating system and the copper dissolution system.

[0048] In electrochemical redox reactions, the gain and loss of electrons at the electrocatalytic anode and cathode are in balance. To reduce copper deposition at the electrocatalytic cathode while avoiding the release of large amounts of residual oxidizing gases that pollute the environment, it is necessary to determine the operating current value of the electrocatalytic power supply at a certain point of normal output in the electrocatalytic gas-liquid reaction tank. By adjusting the amount of oxidizing gas input, the process point at which copper is not deposited at the electrocatalytic cathode can be obtained. This operating current value is then used as a reference point for the corresponding oxidizing gas input. Adjustments are made up to and around this operating current value, and the resulting changes in current are used as a reference point for adjusting the oxidizing gas input to achieve the desired copper dissolution process.

[0049] As a preferred embodiment of the present invention, the copper plating solution contains a small amount of ferric sulfate, which helps the copper plating solution in the electroplating tank to remove monovalent copper ion compounds and copper powder produced by the disproportionation reaction in a timely manner, and acts as a leveling agent for the copper plating layer of the cathode workpiece. Especially in the soluble phosphorus copper anode electroplating process, since the monovalent copper compounds produced in the copper plating solution of the electroplating tank can be oxidized and removed immediately by trivalent iron ions, the electroplating quality is improved more effectively. Preferably, the concentration of trivalent iron ions in the copper plating solution is 0.001-10 g / L; in this preferred embodiment, the iron ions in the copper plating solution mainly play a role in dissolving copper without being replenished by the copper source, so the amount added is small. This can not only oxidize and remove monovalent copper ion compounds in a timely manner, reduce the copper powder produced by the disproportionation reaction, but also avoid corrosion of the cathode workpiece, and act as a leveling agent for the cathode workpiece.

[0050] The present invention can be improved in the following ways: by increasing the temperature of the electrolyte in the electrocatalytic gas-liquid reaction tank and / or by spraying the gas-liquid mixed electrolyte of oxidizing gas toward the electrocatalytic cathode, so as to promote the electrochemical reaction between the electrocatalytic cathode and the oxidizing gas by using the temperature and / or flow rate and / or injection pressure of the electrolyte, thereby helping to achieve the goal of not electrodepositing copper at the electrolytic cathode or maintaining the rate of copper electrodeposited at the cathode within the range allowed by the process.

[0051] The present invention can also be improved in the following ways: the oxidizing gas is preferably oxygen produced in the insoluble anodic electroplating tank, which can reduce production costs and reduce the pollution and harm of oxidizing gas to the environment.

[0052] The present invention can also be improved in the following ways: branch conductors are added to the electrocatalytic anode and / or electrocatalytic cathode to increase the specific surface area of ​​the electrocatalytic anode so that it can electrochemically react with the monovalent copper compound and its disproportionation reaction-produced metallic copper powder from the copper plating solution in the electroplating bath through a collision-interception contact method; and / or to increase the specific surface area of ​​the electrocatalytic cathode so that it can fully react with the oxidizing gas in the gas-liquid mixture. Preferably, the branch conductors on the electrocatalytic anode can be made of the same material as the electrocatalytic anode or other insoluble anode materials, and the branch conductors on the electrocatalytic cathode are preferably made of metallic copper.

[0053] The present invention can also be improved in the following ways: after the electrolyte containing oxidizing bubbles has reacted at the electrocatalytic cathode, the remaining liquid flow containing a small amount of oxidizing bubbles is diverted to the electrolytic anode, so that the copper powder electrolyzed in the original cathode electrolyte reacts with the oxidizing gas and dissolves in the acid solution and / or collides with the electrocatalytic anode to undergo a dissolution reaction, and / or this oxidizing bubble liquid flow is diverted to the soluble metallic copper anode to participate in the metallic copper dissolution reaction at the electrocatalytic anode, so as to eliminate the trace amount of sponge copper electrolyzed at the electrocatalytic cathode and use the remaining small amount of oxidizing gas in the bubble liquid to oxidize the metallic copper anode.

[0054] The present invention can also be improved as follows: an electrolytic cell separator is added to the electrocatalytic gas-liquid reaction tank to divide the electrocatalytic gas-liquid reaction tank into an electrocatalytic anode tank area and an electrocatalytic cathode tank area, with the outlet of the gas-liquid mixer located in the electrocatalytic cathode tank area. The electrolytic cell separator is of two types: one type allows the solution to pass through but effectively prevents solids and bubbles in the electrolyte from passing through; the other type allows only ions in the solution between the two tank areas to pass through while effectively preventing the electrolyte, its solids, and bubbles from passing through. When the amount of oxidizing gas is insufficient, copper powder will be electrodeposited on the electrocatalytic cathode. In this case, the electrolytic cell separator confines the electrodeposited copper powder in the electrocatalytic cathode tank area, reducing or even eliminating the return of the copper powder to the electroplating tank with the copper plating solution that has undergone oxidation treatment in the electrocatalytic anode tank area. Simultaneously, the electrolytic cell separator also effectively prevents short circuits between the electrocatalytic anode and the electrocatalytic cathode. Furthermore, regarding the issue of copper electrodeposition at the electrocatalytic cathode in the electrocatalytic gas-liquid reaction tank operating with the second function, once the copper ion concentration of the anolyte in the electrocatalytic gas-liquid reaction tank meets the process requirements, the electrocatalytic power supply can be shut down or its output voltage adjusted to be equal to or less than 0.34V. This extends the supply of oxidizing gas to the electrocatalytic cathode tank area, causing the copper already electrodeposited on the electrocatalytic cathode to undergo an oxidation reaction and dissolve in sulfuric acid. Alternatively, the current density output by the electrocatalytic power supply can be reduced to slow down the original copper dissolution rate during copper source replenishment. In this case, the same amount of oxidizing gas input as before the adjustment is maintained, ensuring that the copper electrolyzed on the electrocatalytic cathode before the adjustment is oxidized and dissolved, maintaining the original balance between anolyte copper dissolution and cathode copper. When the electroplating operation continues, the copper ion concentration in the anolyte tank area will decrease to the process set value. At this point, the electrocatalytic power supply can be restored to its original output current value to replenish the copper source, thereby resolving the problem of copper electrodeposition at the electrocatalytic cathode.

[0055] The present invention can also be improved as follows: For the electrocatalytic gas-liquid reaction tank with the second function, where copper electrodeposition occurs due to insufficient reaction between the electrocatalytic cathode and the oxidizing gas during the reaction process, a copper-solubilizing electrolysis device is added to immediately dissolve the electrodeposited metallic copper. The copper-solubilizing electrolysis device includes a copper-solubilizing electrolysis power supply, a copper-solubilizing anode, and a copper-solubilizing cathode. Both the copper-solubilizing anode and cathode are located in the space near the electrocatalytic cathode within the electrocatalytic gas-liquid reaction tank. Both the electrocatalytic cathode and the copper-solubilizing anode are made of metallic copper and are electrically connected. The copper-solubilizing anode is connected to the positive terminal of the copper-solubilizing electrolysis power supply, and the copper-solubilizing cathode is connected to the negative terminal. The copper-solubilizing cathode is independently placed next to the electrocatalytic cathode and undergoes an electrocatalytic reaction with the oxidizing gas. During operation, the copper-solubilizing anode dissolves the metallic copper electrodeposited by the electrocatalytic cathode, while the electrocatalytic cathode, in conjunction with the copper-solubilizing cathode, reacts with the oxidizing gas to improve the effect of preventing copper electrodeposition at the electrocatalytic cathode. Preferably, sensors are used to detect changes in the weight of the electrocatalytic cathode and / or changes in the concentration, color, or specific gravity of copper ions in the electrolyte near the electrocatalytic cathode to adjust and control the copper dissolving current of the copper-solubilizing electrolysis power supply. A feedback control system is established to address the issue of copper electrodeposition at the electrocatalytic cathode. The copper-solubilizing cathode material can be the same as the electrocatalytic cathode material. More preferably, both the copper-solubilizing anode and cathode are located in the electrocatalytic cathode area of ​​the electrocatalytic gas-liquid reaction tank with an electrolytic cell separator. The electrolyte in this independent area can be better controlled, making it easier to achieve the desired effect.

[0056] The present invention can also be improved in the following way: using a hot and cold temperature exchanger to control the temperature of the electrolyte in the electrocatalytic gas-liquid reaction tank so that the temperature of the electrolyte meets the process requirements.

[0057] This invention can also be improved in the following ways: Sensors and automatic detection and feeding controllers are used to perform on-site sampling, detection, and data processing of the entire production unit, and to monitor the operation of the unit, thereby achieving automated safe production and production data management. Especially in the copper dissolution process of the electrocatalytic gas-liquid reaction tank with the second function, sensors are installed in the tank to detect the copper ion concentration in the electrolyte near the electrocatalytic anode, and measures are taken to balance the copper plating and electrolytic copper dissolution systems. Specifically, during the copper source replenishment process of the plating solution, when the copper ion concentration in the electrolyte near the electrocatalytic anode reaches the process set value, the electrocatalytic power supply is required to operate in at least one of the following three modes to balance the rate of copper electroplating in the plating tank and the rate of copper oxidation and dissolution in the electrocatalytic gas-liquid reaction tank: ① using an intermittent on / off power-on mode; ② switching between the normal copper dissolution current density of the electrocatalytic power supply and the working current voltage value near the electrolytic decomposition voltage value; ③ adjusting the output current density of the electrocatalytic power supply according to the plating current density, switching between being greater than, equal to, or less than the plating current density. The sensors are selected from at least one of the following: pH meter, specific gravity meter, photoelectric colorimeter, pH meter, oxidation-reduction potentiometer (ORP meter), thermocouple-type copper ion concentration meter, level gauge, thermometer, gas flow meter, weighing meter, conductivity meter, dissolved oxygen meter, liquid flow meter, liquid pressure gauge, and ultrasonic detector. Furthermore, sensors such as pH meter, photoelectric colorimeter, specific gravity meter, ORP meter, thermocouple-type copper ion concentration meter, dissolved oxygen meter, and weighing meter are installed in the electrocatalytic gas-liquid reaction tank to monitor multiple process parameters related to changes in the weight of the electrolyte or electrolytic cathode. At least one of the on-site process parameters measured by the installed sensors can be used as a reference input parameter for the final-stage control system in the cascade control system of the electrocatalytic gas-liquid reaction tank, and the output of the final-stage control system is fed back to control the amount of oxidizing gas introduced, according to its transfer function relationship. The cascade control system in the electrocatalytic gas-liquid reaction tank of this invention uses the copper source replenishment mode of the copper plating solution in the electrocatalytic gas-liquid reaction tank and the electroplating current value or change in electroplating current in the electroplating tank as reference input parameters for the primary control system. The output of the primary control system, obtained through its primary transfer function, is the voltage or current value output by the electrocatalytic power supply. The voltage or current value output by the controlled electrocatalytic power supply from this primary control system is used as the input parameter for the intermediate control system. The transfer function of the intermediate control system is used to obtain the field detection value of the controlled sensor from the intermediate control system. The field parameters detected by this sensor in the electrolyte of the electrocatalytic gas-liquid reaction tank or the parameter of the change in the weight of the electrolytic cathode are used as the input parameters for the final control system. The final control system adjusts the oxidizing gas input regulator based on the transfer function of the final control system, ensuring that the oxidizing gas input meets the requirements of the copper dissolution process.Alternatively, a cascaded feedback control system of four or more levels can be established by installing two or more different types of sensors in the electrocatalytic gas-liquid reaction tank to achieve more precise control of the reaction process. Simultaneously, the output current of the electrocatalytic power supply can be adjusted by detecting the copper ion concentration in the reaction liquid within the tank. The process parameters detected in the electrolyte of the electrocatalytic gas-liquid reaction tank can include copper ion concentration, dissolved oxygen content, acidity, ORP, specific gravity, and photoelectric colorimetric values. The preferred sensor for detecting the copper ion concentration in the electrolyte installed in the electrocatalytic gas-liquid reaction tank is a photoelectric colorimeter.

[0058] ORP meters are used to detect and control the redox reaction of solutions under relatively stable sulfuric acid and copper sulfate concentrations. The on-site detection values ​​can indirectly express the concentration of oxidizing gases or ferric ions in the tested solution, expressed in mV.

[0059] The weighing meter is used to detect the weight change of metallic copper electrodeposited at the electrocatalytic cathode in the electrocatalytic gas-liquid reaction tank with a second function. The working current of the copper electrolysis power supply is adjusted according to the original value set by the weighing meter to solve the problem of copper electrodeposited at the electrocatalytic cathode.

[0060] The conductivity meter is used to detect the concentration of sulfuric acid or copper sulfate.

[0061] Gas flow meters are used to detect and control the amount of oxidizing gaseous reactants introduced.

[0062] A hydrometer is used to detect the concentration of copper sulfate or sulfuric acid in copper plating solution.

[0063] Liquid pressure gauges are used to detect and control the pressure of fluids flowing in pipelines and to adjust the flow rate.

[0064] Photoelectric colorimeters are used to detect the color of copper plating solutions and obtain the copper ion concentration value from it.

[0065] Ultrasonic detectors are used to detect and control the amount of soluble phosphorus copper and metallic copper anodes in titanium baskets during electroplating operations.

[0066] Dissolved oxygen meters are used to detect the oxygen content in electrolytes and assist in the control of the amount of oxidizing gas introduced and / or to adjust and control the output voltage and / or current of electrocatalytic power supplies.

[0067] A pH meter is used to measure the concentration of sulfuric acid in copper plating solutions. Preferably, a chemical titration pH meter is selected.

[0068] The present invention can also be improved in the following ways: at least two electrocatalytic gas-liquid reaction tanks are used, wherein part of the electrocatalytic gas-liquid reaction tank uses an insoluble electrocatalytic anode, which is used alone to promptly reduce monovalent copper compounds and / or copper powder; the other part of the electrocatalytic gas-liquid reaction tank uses metallic copper as the electrocatalytic anode, which is used alone to replenish the copper source of the electroplating solution; thereby enabling the timely reduction of monovalent copper compounds and / or copper powder, while also enabling faster and more accurate replenishment of the copper source of the copper plating solution.

[0069] The present invention can also be improved in the following way: when two or more electrocatalytic gas-liquid reaction tanks are used in combination, the electrocatalytic gas-liquid reaction tanks are connected in parallel and / or in series through exhaust gas pipes to perform electrocatalytic oxidation treatment on the copper plating solution. That is, the electrocatalytic gas-liquid reaction tank is divided into two or more stages. The exhaust gas containing oxidizing gas from the first stage electrocatalytic gas-liquid reaction tank is diverted to the second stage electrocatalytic gas-liquid reaction tank in series for use, and / or the exhaust gas containing oxidizing gas from two or more first stage electrocatalytic gas-liquid reaction tanks is collected in parallel and diverted to the second stage electrocatalytic gas-liquid reaction tank for use, which satisfies the needs of large-scale production, saves energy and reduces environmental pollution.

[0070] The present invention can also be improved in the following ways: An ultrasonic vibrating stirrer is used to stir the gas-liquid mixture in the electrocatalytic gas-liquid reaction tank and to disperse and refine the bubbles in the electrolyte. This allows the dispersed and refined oxidizing gas bubbles to have more opportunities to contact and react with monovalent copper compounds and / or copper powder impurities in the copper plating solution, promoting the reaction and dissolution of cuprous chloride or copper powder. During operation, the energy intensity emitted by the ultrasonic vibrating stirrer should be appropriately controlled to avoid damaging the additive components.

[0071] The second objective of this invention is achieved through the following scheme.

[0072] An apparatus for dissolving metallic copper in an acidic copper plating solution, characterized in that it comprises an electroplating tank, an electrocatalytic gas-liquid reaction tank, an electroplating tank outlet pipe, an electroplating tank return pipe, an electrocatalytic gas-liquid reaction tank inlet pipe, a solution flow power device, an oxidizing gas input regulator, an oxidizing gas supply source, and an automatic detection and feeding controller.

[0073] During operation, the device establishes a liquid circulation loop between the electroplating tank and the electrocatalytic gas-liquid reaction tank. A device operation control system is established within the device, which comprises the electroplating tank, the electrocatalytic gas-liquid reaction tank, the oxidizing gas supply source, and the oxidizing gas input regulator. A cascade control system within the electrocatalytic gas-liquid reaction tank controls the gas-liquid reaction process. The primary control system of the cascade control system in the electrocatalytic gas-liquid reaction tank selects the copper source replenishment process mode parameters, electroplating current value, and / or change in electroplating current as reference input parameters. Based on the primary transfer function relationship, the primary control system output controlled parameters are obtained, namely the voltage and / or current value output by the electrocatalytic power supply. These primary output controlled parameters are used as input parameters for the final control system. After processing using the final control system's transfer function relationship, the final output controlled target oxidizing gas input amount is obtained, and the actual amount of oxidizing gas input is controlled by the oxidizing gas input regulator.

[0074] The electroplating tank is an existing acidic copper sulfate copper plating solution electroplating tank, and its electroplating power supply can adjust the voltage and / or current output values ​​according to the production situation.

[0075] The electrocatalytic gas-liquid reaction tank is equipped with an electrocatalytic anode, an electrocatalytic cathode, a first gas-liquid mixer, and an electrocatalytic power supply with output adjustment. The positive terminal of the electrocatalytic power supply is connected to the electrocatalytic anode, and the negative terminal of the electrocatalytic power supply is connected to the electrocatalytic cathode. The electrocatalytic anode is an insoluble anode assembly, or a soluble copper anode loaded in a copper collection tank, or a combination of an insoluble anode assembly and a soluble copper anode loaded in a copper collection tank.

[0076] The electroplating tank outflow pipe is a liquid flow pipe that draws part of the copper plating solution from the electroplating tank to the electrocatalytic gas-liquid reaction tank. One end of the pipe is connected to the liquid outlet of the electroplating tank or placed in the electroplating tank, and the other end of the pipe is connected to the liquid inlet pipe of the electrocatalytic gas-liquid reaction tank or connected to the tank into which the solution flows into the liquid inlet pipe of the electrocatalytic gas-liquid reaction tank.

[0077] The electroplating tank return pipe is a pipe that returns the copper plating solution that has undergone electrocatalytic oxidation treatment to the electroplating tank. One end of the pipe is connected to the inlet of the electroplating tank or placed in the electroplating tank, and the other end of the pipe is connected to the outlet of the electrocatalytic gas-liquid reaction tank through the pipe of the solution flow power equipment, or connected to the pipe of the tank containing the copper plating solution that has undergone electrocatalytic oxidation treatment through the solution flow power equipment.

[0078] The solution flow power device is located on the connecting pipe between the electroplating tank return pipe and the outlet pipe of the electrocatalytic gas-liquid reaction tank. It is the power device that draws the electrocatalytically oxidized copper plating solution back from the electrocatalytic gas-liquid reaction tank to the electroplating tank, allowing the copper plating solution to circulate and participate in the reaction between the electroplating tank and the electrocatalytic gas-liquid reaction tank via the flow pipe. Specifically, the solution flow power device is a pump and / or a tank with high liquid flow potential. When a pump is used as the solution flow power device, its inlet is connected to the outlet pipe of the electrocatalytic gas-liquid reaction tank, and its outlet is connected to the inlet pipe of the electroplating tank return pipe; or its inlet is connected to the outlet pipe of the tank containing the electrocatalytically oxidized copper plating solution, and its outlet pipe is still connected to the inlet pipe of the electroplating tank return pipe. When a tank with high potential energy for liquid flow is used as a solution flow power device, the high potential energy tank is a tank that contains copper plating solution that has undergone electrocatalytic oxidation treatment, and its outlet is connected to the inlet of the return pipe of the electroplating tank.

[0079] The inlet of the liquid inlet pipe of the electrocatalytic gas-liquid reaction tank is connected to the outlet of the electroplating tank outlet pipe, or connected to the outlet pipe of the tank containing the liquid flowing out of the electroplating tank, with the outlet located inside the electrocatalytic gas-liquid reaction tank.

[0080] The automatic detection and feeding controller can be a logic program control device composed of relays, a logic program control device composed of semiconductor devices, or a control device combined with operator-assisted control. The automatic detection and feeding controller is used to control the operation system of the entire device and to establish separate cascade control systems for each electrocatalytic gas-liquid reaction tank to ensure the orderly reaction in the tank. The automatic detection and feeding controller uses the copper source replenishment mode of the copper plating solution and the electroplating current value and / or the change in electroplating current in the cascade control system of the electrocatalytic gas-liquid reaction tank as the reference input parameters for the primary control system. During the process, the voltage or current of the electrocatalytic power supply, the output parameters of the primary control system, are adjusted and controlled through the transfer function relationship of the primary control system. These primary output controlled parameters (voltage and / or current of the electrocatalytic power supply) are then used as the input parameters of the final control system to regulate the final target of the oxidizing gas input regulator.

[0081] The oxidizing gas supply source is the natural atmosphere, an oxygen generator, an ozone generator, and an oxidizing gas storage tank, wherein the natural atmosphere can be considered as a large oxidizing gas storage tank. The oxygen generator is preferably an electrolytic oxygen generator and / or a chemical oxygen generator. The gas delivery pipe of the oxidizing gas supply source is connected to the first gas-liquid mixer.

[0082] The oxidizing gas input regulator is used to control the amount of oxidizing gas supplied from the oxidizing gas supply source to the electrocatalytic gas-liquid reaction tank. Specifically, it controls the output of oxygen or ozone generators or the output of oxidizing gas storage containers. The oxidizing gas input regulator can be categorized by control method into pipeline gate opening / closing regulators, motor speed control regulators, power supply regulators for electrolytic oxygen generators, and raw material feeding regulators for chemical oxygen generators. The oxidizing gas input regulator adjusts the gas input flow rate according to the output parameters of the electrocatalytic power supply. There are several ways to install oxidizing gas input regulators, including: ① Installed on the output pipeline of a high-pressure container storing oxidizing gas, adjusting the gas flow rate through valve operation; ② Installed on the gas booster pump providing the pressure difference in a bubbling-type first gas-liquid mixer, controlling the input of oxidizing gas by adjusting the speed of the pump's moving parts; ③ Installed on the liquid flow variable frequency pump of a vacuum jet-type first gas-liquid mixer, adjusting the flow rate of oxidizing gas drawn in by the vacuum jet under negative pressure using variable frequency speed regulation, or using a pipeline gate regulator installed on the vacuum jet's negative pressure intake pipeline to adjust the amount of oxidizing gas drawn in by the vacuum jet; ④ Installed on the electrolysis power supply of an electrolytic oxygen generator, controlling the oxygen production by adjusting the electrolysis current; ⑤ Installed on a chemical oxygen generator, controlling the speed of the raw material feeder or the amount of raw material fed in to regulate and control the oxygen production; ⑥ Installed on an ozone generator to adjust the ionization voltage and / or oxygen supply, thereby controlling the amount of ozone produced for the reaction. The oxidizing gas input regulator controls the feeding of oxidizing gas materials according to process requirements, so as to achieve the purpose of dissolving copper by electrolyzing a small amount of copper within the range of the electrolytic cathode of the electrocatalytic gas-liquid reaction tank without electrodepositing copper or electrodepositing a small amount of copper within the range of the electrodeposit rate allowed by the process, and ensure safe production.

[0083] When all the electrocatalytic anodes are insoluble anode components, the electrocatalytic gas-liquid reaction tank is only used to reduce cuprous chloride and / or copper powder in the copper plating solution, or to add the function of oxidizing and regenerating ferrous ions in the copper plating solution. However, when the electrocatalytic anode is a soluble copper anode loaded in a copper collection tank, or a combination of the two with insoluble anode components, the electrocatalytic gas-liquid reaction tank also has the function of electrolyzing and dissolving a large amount of copper to replenish the copper source of the copper plating solution, that is, it has the second function mentioned above.

[0084] The insoluble anode assembly is a granular and / or grid-like and / or filament-like and / or honeycomb-like insoluble anode conductor, specifically selected from one or more of graphite, titanium, platinum, gold, and titanium-based coating materials. Preferably, the insoluble anode assembly uses granular and / or grid-like and / or filament-like and / or honeycomb-like titanium and / or titanium-based coating materials, which can reduce equipment material costs and has a simple structure and large specific surface area. Directly using titanium anodes can result in a high interfacial resistance between the passivation film and the electrolyte due to the thick passivation film and few active sites, leading to a high cell voltage between the two electrodes when the electrocatalytic power supply outputs a certain electrolytic current value. However, in scenarios where the copper plating solution contains cuprous chloride and / or copper powder, the electrocatalytic power supply can still meet the process requirements by operating at a safe voltage below 24V, achieving a low current density for micro-electrolysis.

[0085] The copper collection tank is made of a combination of insoluble conductive and non-conductive materials. The copper collection tank allows at least a portion of the copper placed within it to be conductively connected to the positive electrode of the electrocatalytic power supply. When the copper collection tank is entirely made of insoluble conductive material, its structure may have through holes or no through holes connected to the positive electrode of the electrocatalytic power supply, or the copper placed in the collection tank may be conductively connected to the positive electrode of the electrocatalytic power supply. When the copper collection tank is made of non-conductive material or uses insoluble conductive material wrapped in non-conductive material, a through-hole structure is required to allow electric field lines to pass through and reach the tank. The bottom of the tank is equipped with an insoluble conductive pad, which is directly connected to the positive electrode of the electrocatalytic power supply and / or connected through the insoluble conductive material wrapped in non-conductive material within the tank before being conductively connected to the positive electrode of the electrocatalytic power supply, making the copper loaded within it a soluble anode when energized. Preferably, the non-conductive material of the copper plating tank is a polymer resin. Preferably, the material of the insoluble conductor in the copper plating tank that contacts the copper plating solution is titanium, and the insoluble conductor encapsulated in the tank by the non-conductive material is one or more of the following materials: titanium, platinum, gold, graphite, titanium-based coating material, copper, stainless steel, silver, or alloys thereof.

[0086] The electrocatalytic cathode is a conductor, specifically selected from one or more of the following: copper, stainless steel, titanium, platinum, gold, silver, or alloy conductors of the above metals, titanium-based coating materials, and graphite. Preferably, the material is selected from metallic copper.

[0087] The first gas-liquid mixer is a bubbling gas-liquid mixer and / or a vacuum jet gas-liquid mixer, which is equipped with an air inlet and / or an air inlet pipe to introduce oxidizing gas in the form of positive or negative pressure to mix with the copper plating solution to form a gas-liquid mixture reactant for chemical reaction in the electrocatalytic gas-liquid reaction tank. The outlet of the first gas-liquid mixer faces the electrocatalytic cathode or is placed near the electrocatalytic cathode.

[0088] The present invention can also be improved as follows: Sensors are added to at least one container and / or at least one pipeline and / or each electrocatalytic gas-liquid reaction tank in the device's operation control system, and an automatic detection and feeding controller is used to sample and process the device's on-site data to ensure the device operates according to process requirements. For sensors installed in the electrocatalytic gas-liquid reaction tanks within the device, the automatic detection and feeding controller processes the on-site detection data from one or more installed sensors, using the actual measured values ​​from the sensors as input parameters or output parameters for intermediate-level control systems. This establishes a three-level or higher control system (primary, intermediate, and final levels) constituting a feedback control system, enabling precise, rapid, and safe chemical reaction control of the final target oxidizing gas input regulator. The sensors include at least one selected from a pH meter, hydrometer, photoelectric colorimeter, pH meter, oxidation-reduction potentiometer (ORP meter), dissolved oxygen meter, electrocoupled copper ion concentration meter, level gauge, turbidity meter, thermometer, gas flow meter, liquid flow meter, liquid pressure gauge, weighing meter, and ultrasonic detector.

[0089] Preferably, a hydrometer and / or photoelectric colorimeter and / or pH meter and / or conductivity meter and / or electrocouple-type copper ion concentration meter are installed in the electrocatalytic gas-liquid reaction tank with the second function. These are used to detect the copper ion concentration in the electrolyte near the electrocatalytic anode. The copper ion concentration value set by the process monitors the switching of the electrocatalytic power supply between the second and first functional operating states, and the repeated switching between these states. It also monitors the transition between a state where the total current output by the electrocatalytic power supply in the original second functional operating state is greater than or equal to the electroplating current value, and a state where the output current is reduced to below the electroplating current value, resulting in a low copper dissolution capacity. The use of sensors to perform on-site data detection and processing of copper ion concentration in the solution of the electrocatalytic gas-liquid reaction tank better utilizes the copper dissolution performance of the electrocatalytic gas-liquid reaction tank in balancing copper deposition during electroplating and copper dissolution during electrolysis.

[0090] The present invention can be improved in the following way: the electrocatalytic cathode is a granular and / or grid-like and / or filament-like and / or honeycomb-like conductive material to increase the specific surface area of ​​the electrocatalytic cathode. The larger the specific surface area of ​​the electrocatalytic cathode, the better it can achieve collisional contact reaction with the bubbles of oxidizing gas, thereby improving the efficiency of the electrochemical reduction reaction of the oxidizing gas.

[0091] The present invention can also be improved in the following ways: the electrocatalytic cathode is placed above the outlet of the first gas-liquid mixer, and / or downstream of the liquid flow containing oxidizing bubbles. This utilizes the natural upward movement of bubbles in the liquid and their flow with the liquid flow to maximize opportunities for collision and prolong the contact time between the oxidizing bubbles and the electrocatalytic cathode, thus facilitating the reaction. Preferably, increasing the height of the electrocatalytic cathode and extending the collision and contact time between the oxidizing bubbles and the electrocatalytic cathode during their ascent further promotes the electrocatalytic reaction.

[0092] The present invention can also be improved in the following way: the electrocatalytic anode is placed in the path of the liquid flow from the direction of the electrocatalytic cathode, and the electrocatalytic anode is used to intercept cuprous chloride and / or copper powder in the liquid flow for oxidation and dissolution reaction.

[0093] The present invention can also be improved in the following way: the outlet of the liquid inlet pipe of the electrocatalytic gas-liquid reaction tank is oriented towards the electrocatalytic anode, so that the cuprous chloride and / or copper powder in the copper plating solution drawn from the electroplating tank can quickly collide and react with the anode, and at the same time mix with the liquid flow coming from the direction of the electrocatalytic cathode, so that the cuprous chloride and / or copper powder react with the oxidizing bubbles to generate copper sulfate.

[0094] The present invention can also be improved as follows: a bubble collector is added to the electrocatalytic cathode tank area to collect the residual oxidizing gas that has not participated in the reaction in the electrocatalytic cathode tank area, and then returns it to the area below or near the electrocatalytic cathode through a liquid circulation stirrer in the electrocatalytic cathode tank area to continue participating in the electrochemical reaction of the electrocatalytic cathode, so that the oxidizing gas material can be fully utilized. Preferably, the feed hood of the bubble collector is placed above the electrocatalytic cathode, and its outlet is connected to the electrocatalytic cathode tank area through a liquid circulation stirrer.

[0095] The above improvements can fully utilize oxidizing gases for reaction by adjusting the electrode positions of the electrocatalytic anode and cathode, and control the reuse of remaining oxidizing gas bubbles to reduce the emission of unreacted oxidizing gases, thereby improving reaction efficiency and reducing environmental pollution.

[0096] The present invention can also be improved in the following ways: An electrolytic cell separator is added to the electrocatalytic gas-liquid reaction tank to divide it into an electrocatalytic anode tank area and an electrocatalytic cathode tank area. This allows for better utilization of the oxidizing gas circulating in independent tank areas to participate in the electrochemical reaction at the electrocatalytic cathode and in the oxidation reaction of copper powder in the electrocatalytic anode tank area. Simultaneously, the electrolytic cell separator prevents the copper powder electrodeposited at the electrocatalytic cathode from flowing back into the electroplating tank and avoids short circuits between the electrocatalytic anode and cathode during operation. There are two types of electrolytic cell separators: the first type is selected from one or more separators chosen from filter membranes, filter cloths, polymer resin microporous plates, and ceramic filter plates that allow electrolyte passage while effectively preventing the passage of solids and bubbles; the second type is selected from one or more membranes chosen from bipolar membranes, cation exchange membranes, anion exchange membranes, and reverse osmosis membranes that allow ions from the electrolyte to pass through while effectively preventing the passage of solids and bubbles.

[0097] The present invention can also be improved as follows: For the electrocatalytic gas-liquid reaction tank with the second function, a copper-solubilizing electrolysis device is added to the electrocatalytic cathode area separated by the electrolysis tank separator to solve the problem of copper deposition on the electrocatalytic cathode. The copper-solubilizing electrolysis device includes a copper-solubilizing electrolysis power supply, a copper-solubilizing anode, and a copper-solubilizing cathode. The copper-solubilizing anode and cathode are located in the electrocatalytic cathode area and are respectively connected to the positive and negative terminals of the copper-solubilizing electrolysis power supply. Both the electrocatalytic cathode and the copper-solubilizing anode are made of metallic copper and are electrically connected. The electro-oxidation function of the copper-solubilizing anode solves the problem of copper deposition on the electrocatalytic cathode. Because both the electrocatalytic cathode and the copper-solubilizing cathode are installed simultaneously in the electrocatalytic cathode area, the reaction area with oxidizing gases is increased, effectively improving the reaction rate with oxidizing gases and helping to eliminate the problem of copper deposition on the electrocatalytic cathode. Preferably, a hydrometer, ORP meter, photoelectric colorimeter, dissolved oxygen meter, weighing meter, and conductivity meter are installed in the electrocatalytic cathode tank area to sample and detect the copper ion concentration in the cathode electrolyte and / or the weight change of the electrocatalytic cathode. The operating current of the copper electrolysis power supply is controlled according to the variables of the above process parameters.

[0098] Preferably, when a copper electrolysis device for dissolving copper is installed in an electrocatalytic gas-liquid reaction tank, the type of sensor to be installed is selected according to the following control methods: ① adding a weighing meter to the electrocatalytic cathode; ② adding at least one of the following at least one location: near the electrocatalytic cathode, in the electrocatalytic cathode tank area, in the pipe connecting the electrocatalytic cathode tank area, or in the container holding the overflow liquid of the electrocatalytic cathode electrolyte; the operating current of the electrocatalytic power supply and / or the copper electrolysis device for dissolving copper is adjusted and controlled according to the detection data of the above sensors, so as to solve the problem of copper electrodeposition at the electrocatalytic cathode through feedback control.

[0099] The present invention can be further improved as follows: a second gas-liquid mixer is added to the electrocatalytic anode tank area, in which case the outlet of the first gas-liquid mixer is located in the electrocatalytic cathode tank area; the second gas-liquid mixer has a structure of either a bubbling type or a vacuum jet type, and its outlet is located in the electrocatalytic anode tank area. The second gas-liquid mixer introduces oxidizing gas into the electrocatalytic anode tank area to oxidize and dissolve cuprous chloride from the copper plating solution, copper powder produced by the disproportionation reaction, and copper powder produced from the soluble copper anode in a sulfuric acid solution containing oxidizing bubbles. This simultaneously prevents the copper powder from adhering to the electrolytic cell separator, forming a secondary electrode, and damaging the electrocatalytic gas-liquid reaction tank. Preferably, the outlet of the second gas-liquid mixer is installed at the lower part of the electrocatalytic anode tank area or near the electrolytic cell separator membrane, utilizing the rising bubbles to better react with the copper powder in the electrolyte.

[0100] The present invention can also be improved as follows: When the separator of the electrolytic cell is selected from at least one of bipolar membrane, cation exchange membrane, anion exchange membrane, and reverse osmosis membrane, a copper plating solution feeder is added to the electrocatalytic cathode cell area to add copper plating solution to the electrocatalytic cathode cell area, causing a portion of the solution to overflow out of the cell area to maintain the stability of the solution composition within the electrocatalytic cathode cell area, thereby solving the problem of compositional changes in the solution within the electrocatalytic cathode cell area during electrolysis. The solution overflowing from the electrocatalytic cathode cell area can be fed into its anode cell area, into another electrocatalytic anode cell area, or into other tanks according to process requirements. The copper plating solution feeder consists of a pump, an adjustable valve, and pipelines.

[0101] The present invention can also be improved as follows: a bubble disperser or a microporous filter tube is connected to the outlet of the first gas-liquid mixer or the second gas-liquid mixer, so that the bubbles flowing from the gas-liquid mixer into the liquid are refined and dispersed to better participate in the reaction. The bubble disperser sprays liquid bubbles in the form of a gas-liquid mixture; the microporous filter tube is a gas tube into which high-pressure oxidizing gas is injected to spray bubbles into the electrolyte to participate in the reaction. The bubble disperser connected to the first gas-liquid mixer has small spray holes in the direction towards the electrocatalytic cathode and / or the fluxing copper cathode. The microporous filter tube is a commercially available product and is placed below the electrocatalytic cathode and / or the fluxing copper cathode. When the first gas-liquid mixer is a vacuum jet gas-liquid mixer, its outlet is preferably connected to a bubble disperser, allowing the bubbles in the liquid sprayed from the bubble disperser to be refined in size and diffused separately to participate in the electrochemical reaction of the electrocatalytic cathode. When the first gas-liquid mixer is a bubbling gas-liquid mixer, its outlet is preferably connected to a microporous filter tube. The gas booster pump directly pumps the oxidizing gas into the microporous filter tube, allowing the bubbles to be squeezed out of the micropores and float up and diffuse into the solution to participate in the reaction.

[0102] The present invention can also be improved in the following way: the outlet of the return pipe of the electroplating tank is located near the cathode plated part, and the copper plating solution is sprayed onto the cathode plated part without affecting the electroplating quality, so as to effectively reduce the monovalent copper compounds and / or copper powder impurities in the copper plating solution around the cathode plated part from this position.

[0103] The present invention can also be improved in the following way: For electroplating tanks using insoluble anodic electroplating process, the liquid inlet of the electroplating tank outlet pipe is set near the cathode plated part, so as to extract the copper plating solution containing more monovalent copper compounds and / or copper powder generated after disproportionation reaction from this position for treatment without affecting its electroplating electric field lines.

[0104] The present invention can also be improved in the following way: For electroplating tanks using a soluble anodic electroplating process, the inlet of the electroplating tank outlet pipe is located near the soluble anode of the electroplating tank and / or inside the titanium basket and / or the titanium basket filter bag, so as to extract the copper plating solution containing a large amount of monovalent copper compounds and / or copper powder generated after disproportionation reaction from this location for treatment without affecting its electroplating electric field lines. Preferably, the electroplating tank outlet pipe is equipped with an adjustable flow valve.

[0105] The present invention can be further improved as follows: A copper-solubilizing electrolysis device is added to the electrocatalytic gas-liquid reaction tank without an electrolytic cell separator. This device includes a copper-solubilizing electrolysis power supply, a copper-solubilizing anode, and a copper-solubilizing cathode. Both the copper-solubilizing anode and cathode are located in the space near the electrocatalytic cathode in the electrocatalytic gas-liquid reaction tank. Both the electrocatalytic cathode and the copper-solubilizing anode are made of metallic copper and are electrically connected. The copper-solubilizing anode is connected to the positive terminal of the copper-solubilizing electrolysis power supply, and the copper-solubilizing cathode is connected to the negative terminal. The copper-solubilizing cathode is independently placed next to the electrocatalytic cathode and performs additional electrocatalytic reactions on the oxidizing gas to improve reaction efficiency. Preferably, the copper-solubilizing current of the copper-solubilizing electrolysis power supply is adjusted and controlled based on changes in the weight of the electrocatalytic cathode and / or the concentration and / or color and / or dissolved oxygen and / or ORP and / or specific gravity and / or conductivity in the electrolyte near the electrocatalytic cathode. Feedback control is used to address the issue of copper electrodeposition at the electrocatalytic cathode. The fluxing copper cathode material can be the same as the electrocatalytic cathode material, and preferably metallic copper material.

[0106] The present invention can also be improved in the following way: when the gas-liquid mixer adopts a bubbling gas-liquid mixer, a one-way valve is installed on the high-pressure gas pipe output of its gas booster pump to prevent the solution from flowing back into the gas booster pump and causing damage to the equipment when the booster pump stops working.

[0107] The present invention can also be improved in the following way: by adding a hot and cold temperature exchanger to ensure that the temperature of the copper plating solution and the solutions in each tank meets the process requirements. The hot and cold temperature exchanger is installed on the tank that requires temperature control or on the pipeline through which the solution requiring temperature control flows.

[0108] The present invention can also be improved in the following ways: an ultrasonic vibrating stirrer is added to the electrocatalytic gas-liquid reaction tank and / or other tanks connected thereto and / or the pipeline through which the electrolyte flows, so that the ultrasonic waves can be used to stir the gas-liquid mixture in the electrocatalytic gas-liquid reaction tank and refine the bubbles of the oxidizing gas, so that the refined bubbles with increased surface area have more opportunities to collide and react with the monovalent copper compounds and copper powder in the gas-liquid mixture reactants.

[0109] The present invention can also be improved in the following way: an ultrasonic rangefinder is installed in the copper metal collection tank to monitor the dissolution status of the copper metal therein, so as to replenish the copper metal in a timely manner and avoid affecting production.

[0110] The present invention can also be improved in the following ways: When multiple electrocatalytic gas-liquid reaction tanks are used in combination to meet the needs of large-scale production, the electrocatalytic gas-liquid reaction tanks are connected in parallel and / or in cascade via exhaust gas pipes to oxidize the copper plating solution. That is, the oxidizing gas exhaust from the preceding electrocatalytic gas-liquid reaction tank is diverted to the following electrocatalytic gas-liquid reaction tank via a cascade route, or the oxidizing gas exhaust from two preceding electrocatalytic gas-liquid reaction tanks is combined and then diverted to a single following electrocatalytic gas-liquid reaction tank. This satisfies the needs of large-scale production while saving energy and reducing environmental pollution.

[0111] This invention can also be improved in the following ways: To better reduce the cuprous chloride and copper powder produced during the electroplating process, an independent electrocatalytic gas-liquid reaction tank is adopted as its dedicated equipment. When replenishing soluble metallic copper anodes, an independent electrocatalytic gas-liquid reaction tank is required as its dedicated equipment. This reduces the influence of other factors during the preparation of high copper ion concentration copper plating solutions, resulting in faster copper dissolution and more precise control of copper ion concentration, thus meeting the quality requirements of the copper source replenishment process.

[0112] The present invention can also be improved in the following ways: a solid-liquid separator is added to precisely filter the oxidized solution, reducing solid impurities in the copper plating solution returned to the electroplating tank. The solid-liquid separator is connected by pipeline to at least one of the electroplating tank, the electrocatalytic gas-liquid reaction tank, the overflow buffer tank, and the temporary storage tank. Structurally and functionally, the solid-liquid separator includes a filter, a centrifuge, and a filter press.

[0113] The present invention can also be improved in the following way: an overflow buffer tank is added to solve the problem of smooth flow of solution between the containers of the device of the present invention. The overflow buffer tank is connected by a pipeline to at least one of the electroplating tank, the electrocatalytic gas-liquid reaction tank, the solid-liquid separator, and the temporary storage tank. Since the reactants are a mixture of gas, liquid, and solid, the bottom of the overflow buffer tank is preferably designed as a funnel-shaped structure so that the material in the tank flows downward in a concentrated manner, reducing the phenomenon of solid matter in the solution sticking to the wall and remaining at the bottom.

[0114] The present invention can also be improved in the following way: an exhaust gas treatment tank is added, the air inlet of which is connected to at least one container in the device as a gas pipeline for environmentally friendly treatment of the escaped exhaust gas.

[0115] Compared with the prior art, the present invention has the following beneficial effects:

[0116] 1. The method of the present invention can effectively reduce the amount of cuprous chloride and copper powder generated by disproportionation reaction in the copper plating solution of the electroplating tank in a timely manner according to the change in the amount generated, which greatly improves the quality of copper plating. Moreover, the oxidation treatment efficiency is high and does not affect the electroplating production. In the process, a cascade control system is used for the electrocatalytic gas-liquid reaction tank to achieve the purpose of copper dissolution production.

[0117] 2. The method of the present invention can be used to replenish copper plating solution in electroplating tanks. Its copper dissolution efficiency and utilization rate of soluble anode copper are higher than those of existing soluble phosphorus copper anode electroplating processes. It can also reduce the cost of treating phosphorus-containing waste liquid, thereby achieving the goal of cost reduction and efficiency improvement.

[0118] 3. The method of the present invention does not use ferric ions as the main oxidant for dissolving copper, thus avoiding corrosion of the cathode plated parts caused by excessively high concentrations of ferric ions in the iron-containing copper plating solution in the electroplating tank during the iron-insoluble anodic electroplating process.

[0119] 4. The device of the present invention will not cause significant damage to the electroplating additives in the copper plating solution during the oxidation and dissolution process. Attached Figure Description

[0120] Figure 1 is a schematic diagram of the apparatus for dissolving metallic copper in an acidic copper plating solution according to Embodiment 1 of the present invention.

[0121] Figure 2 is a schematic diagram of the apparatus for dissolving metallic copper in an acidic copper plating solution according to Embodiment 2 of the present invention.

[0122] Figure 3 is a schematic diagram of the apparatus for dissolving metallic copper in an acidic copper plating solution according to Embodiment 3 of the present invention.

[0123] Figure 4 is a schematic diagram of the apparatus for dissolving metallic copper in an acidic copper plating solution according to Embodiment 4 of the present invention; Figures 4-1 and 4-2 are enlarged views of parts of Figure 4, which together constitute a complete schematic diagram of the apparatus structure of Embodiment 4.

[0124] Figure 5 is a schematic diagram of the apparatus for dissolving metallic copper in an acidic copper plating solution according to Embodiment 5 of the present invention; Figures 5-1, 5-2 and 5-3 are enlarged views of parts of Figure 5, and the three together form a complete schematic diagram of the apparatus structure of Embodiment 5.

[0125] Figure 6 is a schematic diagram of the apparatus for dissolving metallic copper in an acidic copper plating solution according to Embodiment 6 of the present invention.

[0126] Figure reference numerals: 1-Electroplating tank, 2-Electrocatalytic gas-liquid reaction tank, 3-Electroplating power source, 4-Electrocatalytic power source, 5-Electrocatalytic anode, 6-Electrocatalytic cathode, 7-First gas-liquid mixer, 8-Insoluble anode assembly, 9-Metallic copper collection tank, 10-Insulator, 11-Overflow buffer tank, 12-Solid-liquid separator, 13-Automatic detection and feeding controller, 14-Sensor, 15-Metallic copper block, 16-Oxidizing bubble, 1 7-Ozone, 18-Oxygen, 19-Air, 20-Phosphorus copper ball, 21-Copper plating solution, 22-Electrolytic cell separator, 23-Metallic copper powder, 24-Solution in which copper powder has been removed from the copper plating solution, 25-Copper plating solution with high copper ion concentration, 26-Tail gas treatment tank, 27-Valve, 28-Pump, 29-Temporary storage tank, 30-Electroplating tank outlet pipe, 31-Electroplating tank return pipe, 32-Electrocatalytic gas-liquid reaction tank inlet pipe. 33-Solution flow power equipment; 34-Heat exchanger; 35-Oxidizing gas input regulator; 36-Gas booster pump; 37-Electroplating additive; 38-Acidic ferrous sulfate solution; 39-Sulfuric acid; 40-Ultrasonic vibrator; 41-Filter bag; 42-Insoluble conductive pad; 43-Insoluble conductive assembly; 44-Gas collection cover; 45-Bubble disperser; 46-Bubble collector; 47-Cathode plating part; 48-Through hole; 49-Microporous filter tube; 50-One-way valve; 51-Overflow port; 52-Copper plating solution feeder; 53-Copper fluxing electrolytic power supply; 54-Copper fluxing anode; 55-Copper fluxing cathode; 56-Electroplating anode; 57-Non-conductive through-hole plate; 58-Second gas-liquid mixer; 59-Oxygen generator; 60-Ozone generator; 61-Oxidizing gas storage bottle (tank); 62-Natural atmosphere.

[0127] In the accompanying drawings and the following embodiments, "reference numerals" indicate the use of the same type of substance or the same type of component in multiple locations within the apparatus. For example, electrocatalytic gas-liquid reaction tank 2-1 refers to one type of electrocatalytic gas-liquid reaction tank, and electrocatalytic gas-liquid reaction tank 2-2 refers to another type of electrocatalytic gas-liquid reaction tank. Detailed Implementation

[0128] In the following embodiments, the electrocatalytic gas-liquid reaction tank, electrolytic electrode, gas-liquid mixer, copper collection tank, copper fluxing electrolysis equipment, electroplating tank outlet pipe, electroplating tank return pipe, electrocatalytic gas-liquid reaction tank inlet pipe, solution flow power equipment, tail gas treatment tank, temporary storage tank, overflow buffer tank, automatic detection and feeding controller, etc., used are all products of Foshan Yegao Environmental Protection Equipment Manufacturing Co., Ltd., Guangdong Province, China. The heat exchanger, solid-liquid separator, sensor, electrocatalytic power supply, electroplating tank, valve, pump, and chemical raw materials are all commercially available products. Besides those listed above, those skilled in the art can also choose other products with similar performance to those listed above, based on conventional selection, to achieve the purpose of this invention.

[0129] Example 1

[0130] Figure 1 shows a schematic diagram of the apparatus for dissolving metallic copper in an acidic copper plating solution according to Embodiment 1. The apparatus includes an electroplating tank 1, an electrocatalytic gas-liquid reaction tank 2, an electrocatalytic power supply 4, an automatic detection and feeding controller 13, an electroplating tank outlet pipe 30, an electroplating tank return pipe 31, an electrocatalytic gas-liquid reaction tank inlet pipe 32, a solution flow power device 33, an oxidizing gas input regulator 35, a gas booster pump 36, an oxygen generator 59, an ozone generator 60, and a natural atmosphere 62.

[0131] The electroplating tank 1 used in this embodiment is an insoluble anode acidic copper sulfate plating line, which includes an electroplating power source 3, an electroplating anode 56, and a cathode plated part 47. The electroplating anode 56 is a titanium-based coated insoluble anode.

[0132] The electrocatalytic gas-liquid reaction tank 2 is equipped with an electrocatalytic anode 5, an electrocatalytic cathode 6, a first gas-liquid mixer 7, and an electrocatalytic power supply 4. The electrocatalytic anode 5 is a combination of an insoluble conductive body component 43 and a soluble copper anode loaded in a copper collection tank 9. The copper collection tank 9 is a perforated tank made of polymer resin material and has an insoluble conductive body pad 42 at the bottom. The insoluble conductive body component 8 is a sheet-like, grid-like, honeycomb-like, or filament-like insoluble anode conductor with graphite, titanium, platinum, gold, or titanium-based coating.

[0133] The electrocatalytic gas-liquid reaction tank 2 in this embodiment has the first and second functions mentioned above, namely, it can reduce the monovalent copper compounds and copper powder produced by the disproportionation reaction in the copper plating solution, and it can also dissolve metallic copper from outside the electroplating tank to replenish the copper source for the copper plating solution.

[0134] The positive electrode of the electrocatalytic power supply 4 is electrically connected to both the soluble copper metal and the insoluble anode in the electrocatalytic anode 5. The electrocatalytic cathode 6 is made of multi-layered stainless steel and is electrically connected to the negative electrode of the electrocatalytic power supply 4. The conductive wires of the electrocatalytic cathode 6 are wrapped with an insulator 10 to prevent short circuits with the electrocatalytic anode 5. The electrocatalytic cathode 6 is placed above the outlet of the first gas-liquid mixer 7, and the electrocatalytic anode 5 is placed in the flow path of the bubble-containing liquid stream.

[0135] The first gas-liquid mixer 7 is a bubbling gas-liquid mixer, which is connected to a gas booster pump 36 and a manually operated oxidizing gas input regulator 35. The oxidizing gas input regulator 35 is connected to an oxygen generator 59, an ozone generator 60, and the natural atmosphere 62.

[0136] One end of the electroplating tank outlet pipe 30 is connected to the outlet of the electroplating tank 1, and the other end is connected to the inlet pipe 32 of the electrocatalytic gas-liquid reaction tank. The outlet of the inlet pipe 32 faces the electrocatalytic anode 5. One end of the electroplating tank return inlet pipe 31 is connected to the outlet of the electrocatalytic gas-liquid reaction tank 2 via a solution flow power device 33, and the other end is inserted into the copper plating solution of the electroplating tank 1, spraying the oxidized copper plating solution flowing out of the outlet of pipe 31 toward the cathode workpiece.

[0137] The automatic detection and feeding controller 13 is a logic program control device composed of relays, and its design function is simple.

[0138] In this embodiment, the device control system is operated by the operator in accordance with the process requirements and with the help of a simple automatic detection and feeding controller 13. During the operation, the electrocatalytic power supply is adjusted and started / stopped manually according to the electrolytic copper dissolution situation.

[0139] The main components of the acidic copper sulfate plating solution used in this embodiment are 90 g / L sulfuric acid and 150 g / L copper sulfate.

[0140] The oxidizing gas used is a mixture of ozone, oxygen, and air. Air is drawn from the natural atmosphere (19), oxygen is drawn from an oxygen generator that produces oxygen by reacting hydrogen peroxide with manganese dioxide, and ozone is drawn from an ozone generator.

[0141] The operation steps of the method for dissolving metallic copper using an electrocatalytic gas-liquid reaction tank in this embodiment are as follows:

[0142] 1. Add copper plating solution into electroplating tank 1 and electrocatalytic gas-liquid reaction tank 2, add metallic copper 15 into the metallic copper collection tank 9 in electrocatalytic gas-liquid reaction tank 2, and place the cathode plated part 47 in electroplating tank 1.

[0143] 2. When the power is turned on, the automatic detection and feeding controller enters the working state, automatically turns on the gas booster pump 36, and manually adjusts the oxidizing gas input regulator 35. Oxidizing gas is supplied to the electrocatalytic gas-liquid reaction tank 2 through the first gas-liquid mixer 7, and the pump of the solution flow power device 33 is turned on and off every 3 seconds to make the copper plating solution circulate between the electroplating tank 1 and the electrocatalytic gas-liquid reaction tank 2.

[0144] 3. Turn on the electroplating power supply and manually adjust the electroplating current to 100A. Turn on the electrocatalytic power supply 4 and manually adjust its output current to 100A according to the electroplating current value. At this time, the voltage is 24V. Copper powder collision dissolution reaction and monovalent copper compound collision oxidation reaction occur at the electrocatalytic anode 5. The oxidizing gas in the copper plating solution oxidizes the copper powder and monovalent copper compounds. The oxidizing gas undergoes an electrochemical reduction reaction at the electrocatalytic cathode 6. During the reaction, the input amount of oxidizing gas is manually adjusted according to the output current value of the electrocatalytic power supply to prevent copper from being electrodeposited at the electrocatalytic cathode and to prevent a large amount of oxidizing gas from escaping from the electrocatalytic gas-liquid reaction tank and polluting the environment.

[0145] 4. Solution flow power equipment 33 returns the copper plating solution containing 152 g / L of copper sulfate to the electroplating tank to carry out normal electroplating.

[0146] 5. During the entire electroplating and copper dissolution process, the operator only needs to shut down the electrocatalytic power supply for 12 seconds to achieve a basic balance between electroplating copper deposition and electrolytic copper dissolution in the entire system. When the electroplating set time of 20 minutes has elapsed, the electroplating power supply, electrocatalytic power supply, gas booster pump 36, oxidizing gas regulator 35, oxidizer 59, and ozone generator 60 are shut down, and the cathode plated part 47 is removed to complete the electroplating operation.

[0147] Example 2

[0148] Figure 2 shows a schematic diagram of the apparatus for dissolving metallic copper in an acidic copper plating solution according to Embodiment 2. The apparatus includes an electroplating tank 1, an electrocatalytic gas-liquid reaction tank 2, an overflow buffer tank 11, an automatic detection and feeding controller 13, a sensor 14, a tail gas treatment tank 26, an electroplating tank outlet pipe 30, an electroplating tank return pipe 31, an electrocatalytic gas-liquid reaction tank inlet pipe 32, a solution flow power device 33, an oxidizing gas regulator 35, an ozone generator 60, multiple valves, and pumps.

[0149] In this embodiment, the electroplating tank 1 is a soluble phosphorus copper anode electroplating tank, which includes an electroplating power source 3, phosphorus copper balls 20, and a cathode plated part 47. A level gauge equipped with a sensor 14 is used to control the liquid flow circulation between the electroplating tank and the electrocatalytic gas-liquid reaction tank. The phosphorus copper balls 20 are placed in a titanium basket, and the titanium basket is wrapped with a filter bag for filtration.

[0150] The electrocatalytic gas-liquid reaction tank 2 only has the first function described above, namely, it only reduces the monovalent copper compounds and copper powder produced by the disproportionation reaction in the copper plating solution, and oxidizes and regenerates the divalent iron ions in the copper plating solution. The electrocatalytic gas-liquid reaction tank 2 is equipped with an electrocatalytic anode 5, an electrocatalytic cathode 6, a first gas-liquid mixer 7, and an electrocatalytic power supply. The electrocatalytic anode 5 is an assembly of insoluble anode components, specifically composed of sheet graphite as the main body, combined with insoluble anode components 8 made of titanium, platinum, gold, or titanium-based coated filamentous materials. The electrocatalytic cathode 6 is an insoluble conductive component 43, specifically sheet and filamentous platinum metal. The positive electrode of the electrocatalytic power supply 4 is connected to the electrocatalytic anode 5, and its negative electrode is connected to the electrocatalytic cathode 6. The electrocatalytic anode 5 and electrocatalytic cathode 6 are positioned in an oblique horizontal design within the tank structure. The liquid inlet pipe 32 of the electrocatalytic gas-liquid reaction tank sprays copper plating liquid containing monovalent copper compounds and copper powder between the electrocatalytic cathode and anode, which reacts with the oxidizing gas. The unreacted liquid then collides with the electrocatalytic anode to undergo an electrochemical oxidation and dissolution reaction.

[0151] The first gas-liquid mixer 7 is a vacuum jet gas-liquid mixer. Its liquid flow pump 28-2 is controlled by the oxidizing gas input quantity regulator 35 (i.e., frequency converter) to adjust the motor speed and change the input quantity of oxidizing gas. The suction pipe of the first gas-liquid mixer 7 is connected to the ozone output pipe of the ozone generator.

[0152] This embodiment of the device employs two electroplating tank outflow pipes. Electroplating tank outflow pipe 30-1 has a flared cone-shaped suction port positioned at the bottom of the electroplating anode filter bag in electroplating tank 1. The other electroplating tank outflow pipe 30-2, equipped with a flow regulating valve, has its suction port located within the electroplating anode titanium basket filter bag to extract copper plating solution. The two electroplating tank outflow pipes converge and connect to the electrocatalytic gas-liquid reaction tank inflow pipe 32. The outlet of the electrocatalytic gas-liquid reaction tank inflow pipe 32 is positioned between the electrocatalytic anode 5 and the electrocatalytic cathode 6. The outlet of the electrocatalytic gas-liquid reaction tank 2 is connected to the overflow buffer tank 11. The overflow buffer tank 11 is connected to the electroplating tank return pipe 31 via a solution flow power device 33, and further connected to the first gas-liquid mixer 7 via a valve 27-2 and a pump 28-2. The outlet of the electroplating tank return pipe 31 is positioned at the bottom of the cathode plating piece within electroplating tank 1. The overflow buffer tank 11 has a funnel-shaped bottom structure to reduce the accumulation of copper powder produced by the disproportionation reaction in the copper plating solution, so as to ensure that the solution flowing out of the overflow buffer tank contains less copper powder and monovalent copper compounds than the copper plating solution extracted from the electroplating tank.

[0153] The automatic detection and feeding controller 13 is designed to control the operation of the device according to process requirements. A cascade control system is also established for the electrocatalytic gas-liquid reaction tank to control the chemical reaction. The primary control system of the electrocatalytic gas-liquid reaction tank uses the reference input parameters of the copper source replenishment mode of the copper plating solution in the tank and the controlled output voltage of the electrocatalytic power supply as reference input parameters. The final control system uses the output voltage of the electrocatalytic power supply as an input parameter and adjusts the relationship between the frequency converter 35 and the final target value.

[0154] The intake pipe of the exhaust gas treatment tank 26 is connected to the vent pipe of the overflow buffer tank 11. The waste gas absorption reaction liquid in the exhaust gas treatment tank is an acidic ferrous sulfate solution.

[0155] The acidic copper sulfate plating solution used in this embodiment has the following main components: sulfuric acid 75 g / L, copper sulfate 180 g / L, and ferric sulfate 0.0036 g / L (i.e., iron ion concentration of 0.001 g / L). Its electrolytic decomposition voltage is 0.55 V.

[0156] The oxidizing gas used is ozone, which is taken from ozone generator 60.

[0157] The operation steps of the method for dissolving metallic copper using an electrocatalytic gas-liquid reaction tank in this embodiment are as follows:

[0158] 1. Place a titanium basket containing phosphor bronze balls 20 into the electroplating tank 1 as the electroplating anode and place the cathode plated part 47 thereon. Add copper plating solution to the electroplating tank 1, the electrocatalytic gas-liquid reaction tank 2 and the overflow buffer tank 11.

[0159] 2. When the power supply of the device is turned on, the automatic detection and feeding controller 13 issues instructions according to the program to control the pumps of the solution flow power equipment 33 and pump 28-1 to circulate the copper plating solution between the electroplating tank 1, the electrocatalytic gas-liquid reaction tank 2 and the overflow buffer tank 11 under the control of the sensor 14. Pump 28-2 is turned on and, under the control of the oxidizing gas input regulator 35, the first gas-liquid mixer 7 is made to absorb a certain amount of ozone.

[0160] 3. The automatic detection and feeding controller 13 automatically switches on the electroplating power supply according to the program and adjusts the electroplating current to 100A for electroplating operation. It then switches on the electrocatalytic power supply and adjusts its output voltage to 0.78V, which is above the electrolytic decomposition voltage of 0.55V (actual operating value). At this time, the electrolytic current is 4.4A. This ensures that the monovalent copper compounds and copper powder produced by the disproportionation reaction in the copper plating solution are reduced, and divalent iron ions are oxidized to trivalent iron ions, while the copper powder dissolves due to collisions at the electrocatalytic anode 5. Simultaneously, oxidation reactions occur due to collisions between monovalent copper compounds and divalent iron. In the copper plating solution of the electrocatalytic gas-liquid reaction tank 2, oxidizing reactions of oxidizing gases on metallic copper, monovalent copper compounds and divalent iron, as well as oxidation reactions of trivalent iron ions on metallic copper and monovalent copper compounds in the copper plating solution, also occur. During the reaction, the automatic detection and feeding controller 13 automatically adjusts the amount of ozone input reaction according to the output voltage value of the electrocatalytic power supply. Trace amounts of metallic copper are still electro-deposited at the electrocatalytic cathode. The purpose of this design is to reduce the ozone pollution that remains after the reaction in the electrocatalytic gas-liquid reaction tank. That is, the reduction reaction of oxidizing gases and the reduction reaction of slight electro-deposited copper occur on the electrocatalytic cathode 6.

[0161] 4. The exhaust gas escaping from the overflow buffer tank 11 is directed to the exhaust gas treatment tank for environmental protection treatment. The reaction between the exhaust gas and the absorbent is: 6FeSO4 + 3H2SO4 + O3 → 3Fe2(SO4)3 + 3H2O

[0162] 5. The solution flow power device 33 continuously operates to return the copper powder solution from the copper plating solution to the electroplating tank, in which ferric ions are introduced to react with the newly formed monovalent copper ion compounds and / or copper powder in the electroplating tank in an oxidation and dissolution reaction.

[0163] 6. When the electroplating set time of 25 minutes has elapsed, the electroplating power supply and electrocatalytic power supply will be automatically shut off, and the cathode plated part will be removed to complete the electroplating operation. The automatic detection feeding controller 13 will control the gas supply to the first gas-liquid mixer 7 to perform a delayed shutdown operation according to the program, and continue to draw in ozone to oxidize and dissolve the trace amount of metallic copper electrolyzed on the electrocatalytic cathode.

[0164] Example 3

[0165] Figure 3 shows a schematic diagram of the apparatus for dissolving metallic copper in an acidic copper plating solution according to Embodiment 3. The apparatus includes an electroplating tank 1, an electrocatalytic gas-liquid reaction tank 2, two overflow buffer tanks 11, an automatic detection and feeding controller 13, an electroplating tank outflow pipe 30, an electroplating tank return pipe 31, an electrocatalytic gas-liquid reaction tank inflow pipe 32, a solution flow power device 33, an oxidizing gas input regulator 35, a bubble disperser 45, a bubble collector 46, an oxidizing gas storage bottle 61, multiple valves, and pumps.

[0166] The electroplating tank 1 used in this embodiment is a soluble phosphorus copper anode electroplating tank, which includes an electroplating power source 3, an electroplating anode 56 with phosphorus copper balls 20, and a cathode plated part 47; wherein the electroplating anode 56 is a combination of phosphorus copper placed in a titanium basket and wrapped with a filter bag.

[0167] The electrocatalytic gas-liquid reaction tank 2 is equipped with an electrocatalytic anode 5, an electrocatalytic cathode 6, an electrolytic cell separator 22, a first gas-liquid mixer 7, and an electrocatalytic power supply 4. The electrocatalytic anode 5 is an insoluble anode assembly 8.

[0168] The electrocatalytic gas-liquid reaction tank 2 described above only has the first function mentioned earlier, namely, to reduce the monovalent copper compounds and copper powder produced by the disproportionation reaction in the copper plating solution. The electrocatalytic gas-liquid reaction tank 2 uses a filter cloth 22, which is permeable to the electrolyte solution and prevents the passage of monovalent copper compounds, copper powder, and bubbles in the solution, as a separator to divide it into an electrocatalytic anode tank area and an electrocatalytic cathode tank area. Both the electrocatalytic anode 5 and the electrocatalytic cathode 6 are made of titanium metal wire. The first gas-liquid mixer 7 is a vacuum jet gas-liquid mixer, and its outlet is equipped with a bubble disperser 45. A bubble collector 46 is installed above the electrocatalytic cathode 6 in the electrocatalytic cathode tank area, and its outlet is connected to a pipe located below the electrocatalytic cathode 6 in the catalytic cathode tank area via a liquid circulation pump 28-3, allowing the collected solution containing unreacted oxidizing gases to be re-ejected to participate in the reaction.

[0169] The electroplating tank outlet pipe 30 has three horn-shaped suction ports, two of which are located at the bottom of the electroplating anode in the electroplating tank 1, and the other is located at the bottom of the cathode plating workpiece. The outlet of the electroplating tank outlet pipe 30 is connected to the inlet pipe 32 of the electrocatalytic gas-liquid reaction tank. The outlet of the inlet pipe 32 of the electrocatalytic gas-liquid reaction tank is located below the electrocatalytic anode 5. The outlet of the electrocatalytic anode tank area is connected to the overflow buffer tank 11-2. The overflow buffer tank 11-2 is connected to the electroplating tank return pipe 31 through the solution flow power device 33, and the spray nozzle of the electroplating tank return pipe 31 is located around the upper part of the cathode plating workpiece, spraying towards the cathode plating workpiece.

[0170] The outlet of the electrocatalytic cathode cell is connected to the overflow buffer tank 11-1. The overflow buffer tank 11-1 is connected to the first gas-liquid mixer 7 via a pipeline and is used to supply solution to the first gas-liquid mixer 7. The oxidizing gas used is oxygen 18, which is taken from the oxygen cylinder of the oxidizing gas storage bottle 61.

[0171] The automatic detection and feeding controller 13 is programmed with an operating procedure according to process requirements, including a cascade control system program for the electrocatalytic gas-liquid reaction tank. The primary control system of the electrocatalytic gas-liquid reaction tank is related to the controlled relationship between the reference input parameter of the copper source replenishment mode of the copper plating solution and the output voltage of the electrocatalytic power supply. The final control system uses the output voltage of the electrocatalytic power supply as its input parameter and relates it to the input and output of the oxidizing gas input regulator 35, i.e., the frequency converter.

[0172] The main components of the acidic copper sulfate plating solution used in this embodiment are sulfuric acid 75 g / L and copper sulfate 200 g / L, and its electrolytic decomposition voltage is 0.61 V.

[0173] The operation steps of the method for dissolving metallic copper using an electrocatalytic gas-liquid reaction tank in this embodiment are as follows:

[0174] 1. Put a titanium basket containing phosphor bronze balls 20 into the electroplating tank as the electroplating anode and place the cathode plated part 47. Add copper plating solution to the electroplating tank 1, the electrocatalytic gas-liquid reaction tank 2 and the two overflow buffer tanks 11-1 and 11-2. Turn on the power of the device to make the automatic detection and feeding controller 13 enter the working state.

[0175] 2. The automatic detection and feeding controller 13 controls the activation of the pumps of the solution flow power equipment 33 and pump 28-1, and controls the flow rate of pump 28-1 to make the copper plating solution circulate between the electroplating tank 1, the electrocatalytic gas-liquid reaction tank 2 and the overflow buffer tank 11-2. Pump 28-2 is activated and, under the control of the oxidizing gas input regulator 35, the first gas-liquid mixer 7 draws in oxygen and sprays it out from the bubble disperser 45. Pump 28-3 is activated to collect the bubbles in the gas-liquid mixture in the electrocatalytic cathode tank area through the bubble collector 46, and then uses the liquid circulation pump 28-3 to re-inject the oxygen that has not participated in the reaction into the cathode tank area to continue to participate in the reaction.

[0176] 3. The automatic detection and feeding controller 13 issues a command to automatically turn on the electroplating power supply and adjust the electroplating current to 100A for electroplating operation. It also turns on the electrocatalytic power supply and automatically adjusts its output voltage to 0.55V, which is below the electrolytic decomposition voltage of 0.61V, for operation. At this time, the electrolytic current value is 57mA. This allows the monovalent copper compounds in the copper plating solution and the copper powder produced by the disproportionation reaction to collide and dissolve with the electrocatalytic anode 5, thereby reducing the amount of copper powder produced by the disproportionation reaction, while protecting the additives from damage. During the reaction, the automatic detection and feeding controller 13 adjusts the oxygen input according to the output voltage value of the electrocatalytic power supply, so that the electrocatalytic cathode 6 does not electrodeposit copper.

[0177] 4. Pump 28-1 is connected to the electroplating tank to draw copper plating solution from the electroplating tank at a certain flow rate and then to the electrocatalytic gas-liquid reaction tank for treatment. The solution in which copper powder has been removed from the copper plating solution is returned to the electroplating tank through the solution flow power device 33 to reduce monovalent copper compounds and copper powder.

[0178] 5. When the electroplating set time of 35 minutes has elapsed, turn off the electroplating power supply and electrocatalytic power supply, as well as all pumps, and remove the cathode plated parts to complete the electroplating operation.

[0179] Example 4

[0180] Figure 4 shows a schematic diagram of the apparatus for dissolving metallic copper in an acidic copper plating solution according to Embodiment 4. The apparatus includes an electroplating tank 1, three electrocatalytic gas-liquid reaction tanks 2, a metallic copper collection tank 9, three overflow buffer tanks 11, a solid-liquid separator 12, an automatic detection and feeding controller 13, four sensors 14, a temporary storage tank 29, an electroplating tank outlet pipe 30, an electroplating tank return pipe 31, three electrocatalytic gas-liquid reaction tank inlet pipes 32, a solution flow power device 33, two gas booster pumps 36 and two oxidizing gas input regulators 35, a microporous filter tube 49, a one-way valve 50, oxidation sources 59-1 and 59-2, and multiple valves and pumps.

[0181] In this embodiment, the electroplating tank 1 is an insoluble anodic acidic copper sulfate electroplating line with a separated anode and cathode areas, including an electroplating power source 3, an electroplating anode 56, and a cathode plated part 47. Sensors 14-1 and 14-2 are installed in the cathode area of ​​electroplating tank 1; these are a photoelectric colorimeter and a level gauge, respectively, used to detect the copper ion concentration in the cathode copper plating solution and control the liquid level in the cathode area. A gas collecting cover 44-1 is also installed on the top of the anode area of ​​electroplating tank 1 to collect the electrolyzed oxygen. Simultaneously, the anode area of ​​electroplating tank 1 is designated as an oxygen generator 59-1; another oxygen generator 59-2 is an oxygen storage tank 61, both providing oxidizing gaseous reaction raw materials to the electrocatalytic gas-liquid reaction tank 2-1.

[0182] The electrocatalytic gas-liquid reaction tank 2-1 has the first and second functions mentioned above, namely, it can both reduce the monovalent copper compounds and copper powder produced by the disproportionation reaction in the copper plating solution, and dissolve metallic copper from outside the electroplating tank to replenish the copper source for the copper plating solution. The electrocatalytic anode 5-1 is a soluble metallic copper anode made of a metallic copper collecting tank 9, which is connected to the positive terminal of the electrocatalytic power supply 4-1. The metallic copper collecting tank 9 is a through-hole tank made of polymer resin material, and the bottom is padded with an insoluble conductive pad 42. During operation, the copper plating solution flows through the collecting tank 9, and the monovalent copper compounds and copper powder produced by the disproportionation reaction collide with the soluble metallic copper anode, which are then oxidized and dissolved to reduce them. The electrocatalytic cathode 6-1 is a combination of copper sheet and copper wire. The electrocatalytic gas-liquid reaction tank 2-1 uses filter cloth as an electrolytic cell separator 22-2 to divide it into an electrocatalytic anode tank area and an electrocatalytic cathode tank area. The first gas-liquid mixer 7-1 is a bubbling type gas-liquid mixer used for supplying oxidizing gas. Its gas booster pump 36-1 has two intake ports. One intake port is connected via a pipe to the vent of the gas collection cover 44-1 at the top of the anode tank area of ​​the electroplating tank 1, and the other intake port is connected via a pipe to the oxygen storage tank 61. A microporous filter tube 49 is installed at the outlet of the first gas-liquid mixer 7-1 to refine the bubbles and facilitate diffusion. The filter tube is positioned below the electrocatalytic cathode 6-1 and sprays bubbles towards the electrocatalytic cathode 6-1. A sensor 14-3, an ORP meter, is installed in the electrocatalytic cathode tank area of ​​the electrocatalytic gas-liquid reaction tank 2-1 to detect the oxygen content in its cathode electrolyte. A sensor 14-4, a photoelectric colorimeter, is installed in the electrocatalytic anode tank area to detect the copper ion concentration. The sensor 14-4 controls the electrocatalytic power supply 4-1 to select either the second function (electrolytic copper dissolution) or the first function (reduction of monovalent copper compounds and / or copper powder in the copper plating solution).

[0183] The automatic detection and feeding controller 13 controls the operation of the entire equipment. It also programs the logic control relationship for the cascade control system of the electrocatalytic gas-liquid reaction tank 2-1. The primary control system uses the copper source replenishment mode and electroplating current value of the copper plating solution in the electrocatalytic gas-liquid reaction tank as input parameters, relating them to the controlled operating current output by the electrocatalytic power supply. The intermediate control system uses the operating current value output by the electrocatalytic power supply 4-1 as input parameters, relating it to the controlled output parameters of sensors 14-3 and 14-4. The final control system uses the parameter value of sensor 14-3 as input parameters, relating it to the frequency converter of the final controlled target oxidizing gas input regulator 35-1. The parameter value of sensor 14-4 controls the operating current output value of the electrocatalytic power supply. Based on the cascade control system of the electrocatalytic gas-liquid reaction tank 2-1, the process parameters of the electroplating tank are used to regulate the final output target oxidizing gas regulator 35 through each level of the control system.

[0184] The electrocatalytic gas-liquid reaction tank 2-2 only has the first function mentioned above, namely, to reduce the monovalent copper compounds and copper powder produced by the disproportionation reaction in the copper plating solution. The electrocatalytic anode 5-2 is made of wound titanium wire, and the electrocatalytic cathode 6-2 is made of wound gold wire. The first gas-liquid mixer 7-2 is a vacuum jet gas-liquid mixer. The liquid flow pump 28-3 operates in a constant flow mode to draw the oxidizing gas tail gas escaping from the electrocatalytic cathode tank area of ​​the electrocatalytic gas-liquid reaction tank 2-1 as the raw material for the electrocatalytic gas-liquid reaction tank 2-2. That is, its oxidizing gas input rate regulator is fixed by the device design. Its gas inlet is connected to the gas collection cover 44-2 escaping port located at the top of the electrocatalytic cathode tank area of ​​the electrocatalytic gas-liquid reaction tank 2-1. Its liquid outlet is located below the wound gold wire of the electrocatalytic cathode 6-2, and its spray nozzle faces the electrocatalytic cathode 6-2.

[0185] The automatic detection and feeding controller 13 is used to program the logic control relationship of the control system established by the electrocatalytic gas-liquid reaction tank 2-2. Based on the copper dissolution mode selected by the electrocatalytic gas-liquid reaction tank 2-2 itself, it serves as the reference input parameter for the primary control system, determining its output controlled parameter—the output voltage value of the electrocatalytic power supply. The operating voltage value of the electrocatalytic power supply 4-2 is used as the input parameter of the final-stage control system, and the flow rate parameter of the oxidizing gas regulator, i.e., pump 28-3, is designed to be fixed according to requirements using the final-stage transfer function relationship.

[0186] The electrocatalytic gas-liquid reaction tank 2-3 described above only has the first function mentioned earlier, namely, to reduce the monovalent copper compounds and copper powder produced by the disproportionation reaction in the copper plating solution. The electrocatalytic gas-liquid reaction tank 2-3 uses two polymer resin perforated plates as electrolytic cell separators 22-3-1 and 22-3-2, dividing it into a three-part horizontal electrolytic cell with one electrocatalytic anode tank on each side and one electrocatalytic cathode tank in the middle. This prevents the electrocatalytic anode and electrocatalytic cathode from contacting and short-circuiting. The perforations of the two electrolytic cell separators 22-3-1 and 22-3-2 allow the electrolyte solution to pass through but do not allow solid impurities and air bubbles in the electrolyte to pass through. The two electrocatalytic anode tanks are respectively equipped with electrocatalytic anodes, numbered 5-3-1 and 5-3-2, both of which are electrodes combining graphite and platinum wire. The electrocatalytic cathode 6-3 is made of stainless steel wire. The first gas-liquid mixer 7-3 is a bubbling type gas-liquid mixer. It draws air from the natural atmosphere 62 through the suction pipe of the gas booster pump 36-2. A one-way valve 50 is installed on the high-pressure outlet pipe of the first gas-liquid mixer 7-3 to prevent electrolyte backflow when the machine is stopped. The outlet of the first gas-liquid mixer 7-3 is located below the electrocatalytic cathode 6-3.

[0187] The automatic detection and feeding controller 13 establishes a control system for the electrocatalytic gas-liquid reaction tank 2-3. Its primary control relationship is to use the copper dissolution mode selected by the tank 2-3 itself as the reference input parameter, and obtain its output controlled parameter—the output voltage value of the electrocatalytic power supply—through its transfer function relationship. The output working voltage value of the electrocatalytic power supply 4-3 is used as the input parameter of the final control system, and its transfer function relationship is used to regulate the final controlled target frequency converter of the oxidizing gas regulator 35-2 of the gas booster pump 36-2.

[0188] The horn-shaped liquid suction port of the electroplating tank outlet pipe 30 is located at the lower part of the cathode plating part in the cathode tank area of ​​the electroplating tank 1, and the liquid outlet is connected to the liquid inlet pipe 32-1 of the electrocatalytic gas-liquid reaction tank.

[0189] The overflow port of the electrocatalytic anode tank area of ​​the electrocatalytic gas-liquid reaction tank 2-1 is connected to the liquid inlet pipe 32-2 of the electrocatalytic gas-liquid reaction tank through the overflow buffer tank 11-1. The overflow port of the electrocatalytic gas-liquid reaction tank 2-2 is connected to the liquid inlet pipe 32-3 of the electrocatalytic gas-liquid reaction tank through the overflow buffer tank 11-2. The solution overflowing from the previous electrocatalytic gas-liquid reaction tank is diverted to the subsequent electrocatalytic gas-liquid reaction tank to continue the oxidation reaction. The outlet of the liquid inlet pipe 32-1 of the electrocatalytic gas-liquid reaction tank is located in the space below the electrocatalytic anode 5-1 of the electrocatalytic gas-liquid reaction tank 2-1, and its outlet faces the electrocatalytic anode 5-1. The outlet of the liquid inlet pipe 32-2 of the electrocatalytic gas-liquid reaction tank 2-2 is located in the space below the electrocatalytic anode 5-2 of the electrocatalytic gas-liquid reaction tank 2-2, and its outlet faces the electrocatalytic anode 5-2. The outlets of the liquid inlet pipes 32-3-1 and 32-3-2 of the electrocatalytic gas-liquid reaction tank 2-3 are respectively located in the space below the electrocatalytic anodes 5-3-1 and 5-3-2 of the electrocatalytic gas-liquid reaction tank 2-3, and their outlets face the electrocatalytic anodes 5-3-1 or 5-3-2 respectively.

[0190] The overflow ports of the two electrocatalytic anode zones of the electrocatalytic gas-liquid reaction tank 2-3 are connected to the temporary storage tank 29 via overflow buffer tank 11-3 and solid-liquid separator 12. The solid-liquid separator 12 is used to filter insoluble solid impurities in the prepared copper plating solution 25 with high copper ion concentration. The temporary storage tank 29 is connected to the electroplating tank return pipe 31 via solution flow power equipment 33, so that the copper plating solution with high copper ion concentration is returned to the cathode zone of electroplating tank 1 to participate in the reaction according to process requirements.

[0191] Sensors 14-1 and 14-4 are photoelectric colorimeters, sensor 14-2 is a level gauge, and sensor 14-3 is an ORP meter. Sensor 14-1 is used to detect the copper ion concentration of the copper plating solution in the cathode tank area of ​​electroplating tank 1. When the copper ion concentration is lower than the set value, the variable frequency pump 28-1 draws part of the copper plating solution from the electroplating tank into the electrocatalytic gas-liquid reaction tank 2-1. Then, the pump of the solution flow power device 33 adds copper plating solution 25 with a high copper ion concentration to the electroplating tank according to the set value of the level gauge 14-2, so that the copper ion concentration of the copper plating solution is maintained at the original set value, allowing the electroplating to proceed normally. Sensor 14-3 is used to detect the oxidation-reduction potential of the cathode electrolyte in the electrocatalytic gas-liquid reaction tank 2-1, indirectly detecting the copper ion concentration and dissolved oxygen content of the cathode electrolyte. When the ORP value of the cathode electrolyte is lower than the set value, the oxidizing gas input regulator 35 controls the gas booster pump 36-1 to increase the speed and increase the gas supply. Sensor 14-4 photoelectric colorimeter is used to detect the copper dissolution effect of electrocatalytic gas-liquid reaction tank 2-1. When the copper ion concentration reaches the copper source replenishment concentration value set by the process, the output voltage value of electrocatalytic power supply 4-1 is adjusted to the electrolytic decomposition voltage value to suspend the electrolytic copper dissolution reaction. The copper ion concentration set value of the anolyte, i.e. the copper source replenishment liquid, in electrocatalytic gas-liquid reaction tank 2-1 is 3g / L higher than the copper ion concentration value set by the electroplating process in the copper plating solution of the electroplating tank, so that the copper plating solution is constantly circulated.

[0192] The main components of the acidic copper sulfate plating solution used in this embodiment are 225 g / L sulfuric acid and 50 g / L copper sulfate; its electrolytic decomposition voltage is 0.51V, that is, the set value of the copper ion concentration detected by sensor 14-1 is 19.9 g / L, and the set value of the copper ion concentration detected by sensor 14-4 is 22.9 g / L.

[0193] The oxidizing gas used in electrocatalytic gas-liquid reaction tank 2-1 is oxygen escaping from the anode area of ​​the electroplating tank and an external oxygen source 61. The oxidizing gas used in electrocatalytic gas-liquid reaction tank 2-2 is the tail gas containing oxidizing gas escaping from the cathode area of ​​electrocatalytic gas-liquid reaction tank 2-1. Electrocatalytic gas-liquid reaction tank 2-3 uses air.

[0194] The operation steps of the method for dissolving metallic copper using an electrocatalytic gas-liquid reaction tank in this embodiment are as follows:

[0195] 1. Add copper plating solution to electroplating tank 1, three electrocatalytic gas-liquid reaction tanks and three overflow buffer tanks. Add copper blocks 15 to the copper collection tank 9 in electrocatalytic gas-liquid reaction tank 2-1. Place the cathode plating part 47 into electroplating tank 1. Turn on the power of the device to enable the automatic detection and feeding controller 13 to enter the working state, sample and process the field data of each sensor and control the operation of the device.

[0196] 2. The automatic detection and feeding controller 13 issues a command to control all pumps to start, so that the copper plating solution circulates through each tank. The electroplating power supply 3 is turned on, and the three electrocatalytic power supplies 4-1, 4-2 and 4-3 are turned on. The oxidizing gas input regulator 35-1 controls the operation of the gas booster pump 36-1, while the gas booster pump 36-2 is regulated by the oxidizing gas input regulator 35-2.

[0197] 3. Before the electroplating operation, the automatic detection and feeding controller 13 automatically selects the second function setting for copper dissolution of electrocatalytic power supply 4-1, and selects the first function setting for electrocatalytic power supplies 4-2 and 4-3. The electroplating current is then adjusted to 100A. Based on the electroplating power supply value, the output current of electrocatalytic power supply 4-1 is adjusted to 130A, with a voltage of 7.2V, ensuring a copper source replenishment for the copper plating solution. The output voltage of electrocatalytic power supply 4-2 is adjusted to 0.8V, with an output current of 5.6A. The output voltage of electrocatalytic power supply 4-3 is adjusted to 0.51V, with an output current of 630mA, ensuring the reaction proceeds without damaging the additives in the copper plating solution. Copper dissolution and oxidation of monovalent copper compounds occur at the anodes of each electrocatalytic power supply, while oxidizing gases in the copper plating solution of each electrocatalytic gas-liquid reaction tank oxidize both the copper and monovalent copper compounds.

[0198] 4. During the reaction process, the automatic feeding controller 13, according to the pre-programmed procedure, adjusts the oxidizing gas input regulators 35-1 and 35-2 of each electrocatalytic gas-liquid reaction tank through the control system, so that each electrocatalytic cathode undergoes an electrochemical reduction reaction with the oxidizing gas, preventing copper from being electrodeposited from any of the electrocatalytic cathodes. Additionally, the variable frequency pump 28-1, controlled by sensor 14-1, draws a portion of the copper plating solution from the electroplating tank into the electrocatalytic gas-liquid reaction tank 2-1. The photoelectric colorimeter 14-4 detects the copper ion concentration in the anolyte of the electrocatalytic gas-liquid reaction tank 2-1. When the concentration reaches the set value of the copper source replenishment solution, the electrocatalytic power supply 4-1 is controlled to adjust its output voltage to 0.51V to continue operation. The original output current of 130A is restored to operation only after the detection value of sensor 14-4 drops back to a copper ion concentration of 22 g / L.

[0199] 5. The solution flow power device 33, under the control of the level gauge 14-2, feeds copper plating solution 25 with a high copper ion concentration into the electroplating tank, so that the electroplating tank can operate normally.

[0200] 6. When the electroplating set time of 40 minutes has elapsed, the electroplating power supply, all electrocatalytic power supplies, and the corresponding gas booster pumps controlled by the oxidizing gas input regulators are turned off, all pumps are turned off, and the oxygen storage tank 61 is closed. The cathode plated part 47 is then removed to complete the electroplating operation.

[0201] The characteristic of this embodiment is that the device utilizes the copper source replenishment function of the electrocatalytic gas-liquid reaction tank 2-1, and the copper powder reduction function of electrocatalytic gas-liquid reaction tanks 2-2 and 2-3 in the copper plating solution of tank 2-1. After each electrocatalytic power supply is independently selected, the electrocatalytic gas-liquid reaction tank 2-1 with the copper source replenishment function can control the copper dissolution by having the output current of the electrocatalytic power supply follow the changes in the electroplating current, and switch between function one and function two based on the copper ion concentration in the copper plating solution of reaction tank 2-1. The other electrocatalytic power supplies 4-2 and 4-3 are adjusted to operate directly at the electrolytic decomposition voltage of 0.51V or at a higher electrolytic decomposition voltage to reduce the copper powder in the copper plating solution, and perform oxidation copper dissolution operation under the protection of additives.

[0202] In addition, the electrocatalytic gas-liquid reaction tank 2-1 uses oxygen 18-1 escaping from the electroplating tank and oxygen 18-2 output from the external oxygen source as the main oxidant raw materials. The oxygen-containing tail gas escaping from the pre-stage electrocatalytic gas-liquid reaction tank 2-1 is diverted to the post-stage electrocatalytic gas-liquid reaction tank 2-2 in a cascade manner for full utilization, which reduces environmental pollution and saves production raw materials.

[0203] Example 5

[0204] Figure 5 shows a schematic diagram of the apparatus for dissolving metallic copper in an acidic copper plating solution according to Embodiment 5. The apparatus includes an electroplating tank 1, four electrocatalytic gas-liquid reaction tanks 2, five overflow buffer tanks 11, a solid-liquid separator 12, an automatic detection and feeding controller 13, nineteen sensors 14, a tail gas treatment tank 26, a temporary storage tank 29, one electroplating tank outlet pipe 30, two electroplating tank return pipes 31, five electrocatalytic gas-liquid reaction tank inlet pipes 32, solution flow power devices 33-1 and 33-2, three heat exchangers 34, four oxidizing gas input regulators 35, two ultrasonic vibrating stirrers 40, two copper plating solution feeders 52, a copper dissolving electrolytic power supply 53, a copper dissolving anode 54, a copper dissolving cathode 55, three oxygen generators 59, one ozone generator 60, and multiple valves and pumps.

[0205] In this embodiment, the electroplating tank 1 is an acidic copper sulfate bright electroplating line with an insoluble anode, including an electroplating power supply 3, an electroplating anode 56, a cathode plated part 47, and a sensor 14-2; the sensor 14-2 is a photoelectric colorimeter. The electroplating anode 56 is wrapped with a filter bag 41, and the top of the filter bag 41 has a gas collecting cover 44, which restricts the oxygen electrolyzed by the electroplating anode to escape only from the filter bag opening and be collected by the gas collecting cover 44, serving as an oxygen generator 59-1.

[0206] The oxygen generator 59-2 is an electrolyzer for producing oxygen by electrolyzing sulfuric acid solution. The oxygen output is controlled by adjusting the current density output of its electrolysis power supply. The oxygen generator 59-3 is a reaction tank for producing oxygen by reacting hydrogen peroxide with manganese dioxide. The oxygen output is controlled by adjusting the amount of hydrogen peroxide added and the feeding rate.

[0207] The ozone generator 60 is a commercially available product that uses corona discharge to ionize oxygen and generate ozone. The ozone output is controlled by adjusting the voltage of the high-voltage electric field.

[0208] The automatic detection and feeding controller 13 has a built-in device running program and runs automatically according to the process flow design.

[0209] The electrocatalytic gas-liquid reaction tank 2-1 only has the first function described above, namely, to reduce the monovalent copper compounds and copper powder produced by the disproportionation reaction in the copper plating solution, and to oxidize and regenerate the divalent iron ions in the copper plating solution. Both the electrocatalytic anode 5-1 and the electrocatalytic cathode 6-1 are electrodes combining titanium-based coated mesh and titanium coiled wire. The first gas-liquid mixer 7-1 is a vacuum jet gas-liquid mixer, with a gas flow meter 35-1 equipped with a regulating valve installed on its inlet pipe. The outlet of the first gas-liquid mixer 7-1 is located below the electrocatalytic cathode 6-1, while the electrocatalytic anode 5-1 is above the electrocatalytic cathode 6-1 and in the flow path of the oxygen-containing bubble liquid flow. The electrocatalytic gas-liquid reaction tank 2-1 is equipped with a heat exchanger 34-1 and a thermometer as a sensor 14-1 to maintain the solution at 30°C. The automatic detection and feeding controller 13 establishes a cascade control system for the first functional mode of the electrocatalytic gas-liquid reaction tank 2-1. The input parameter of the final control system is the voltage value output by the electrocatalytic power supply. The final control system adjusts the final controlled target value of the oxidizing gas input regulator 35-1 through the transfer function relationship of the final control system, so that the electrocatalytic cathode 6-1 does not electrodeposit copper.

[0210] The electrocatalytic gas-liquid reaction tank 2-2 has the first and second functions mentioned above: it can reduce monovalent copper compounds and copper powder produced by disproportionation reaction in the copper plating solution, oxidize and regenerate divalent iron ions in the copper plating solution, and dissolve metallic copper from outside the electroplating tank to replenish the copper source for the copper plating solution. The electrocatalytic anode 5-2 is composed of a titanium through-hole metallic copper collection tank 9-1 containing metallic copper blocks 15-1 as a soluble anode and titanium coiled wire material as an insoluble anode assembly. The electrocatalytic cathode 6-2 is made of sheet and coiled wire stainless steel. The first gas-liquid mixer 7-2 is a vacuum jet gas-liquid mixer made of polymer resin, equipped with an ultrasonic vibrating stirrer 40-1 for gas-liquid mixing and stirring. Its suction pipe is connected to the oxygen generator 59-2. The outlet of the first gas-liquid mixer 7-2 is located below the electrocatalytic cathode 6-2, while the electrocatalytic anode 5-2 is above the electrocatalytic cathode 6-2 and is located in the flow path of the oxygen-containing bubble liquid flow. The electrocatalytic gas-liquid reaction tank 2-2 is equipped with a heat exchanger 34-2 and sensors 14-3, 14-4, 14-5, and 14-6; sensors 14-3, 14-4, 14-5, and 14-6 are a thermometer, a photoelectric colorimeter, an ORP meter, and an ultrasonic rangefinder, respectively.

[0211] The automatic feeding controller 13 establishes a cascaded control system for the electrocatalytic gas-liquid reaction tank 2-2, simultaneously performing both the first and second functions. The primary control system's reference input parameters are the copper source replenishment mode of the copper plating solution in the electrocatalytic gas-liquid reaction tank and the electroplating current value. The primary output controlled parameter, the current value output by the electrocatalytic power supply 4-2, is obtained using the transfer function relationship of the primary system. The intermediate-level control system takes the primary output controlled parameter as its input parameter, and obtains multiple output controlled parameter values ​​for sensors 14-4, 14-5, and 14-6 through the transfer function relationship of the intermediate level. Sensor 14-4 is used to detect whether the concentration of divalent copper ions in the electrolyte in the tank reaches the required level. If the process setpoint is reached, the input parameter current of the intermediate level will be reduced to decrease the electrolytic copper dissolution rate in the electrocatalytic gas-liquid reaction tank 2-2 to meet the process requirements of copper plating and electrolytic copper dissolution balance. The final stage control system uses the parameters of sensor 14-5 as the input parameters of the final stage, and controls the output current of the electrolytic power supply in the oxidation source 59-2 (i.e., the oxidizing gas input regulator 35-2) to indirectly regulate the oxygen production. Among them, the ultrasonic rangefinder 14-6 is used to control the addition of the metal copper block 15-1.

[0212] The electrocatalytic gas-liquid reaction tank 2-3 has the first and second functions mentioned above: it can reduce monovalent copper compounds and copper powder produced by disproportionation reaction in the copper plating solution, oxidize and regenerate divalent iron ions in the copper plating solution, and dissolve metallic copper from outside the plating tank to replenish the copper source for the copper plating solution. The electrocatalytic anode 5-3 uses a titanium-material through-hole copper collecting tank 9-2 to hold copper blocks 15-2 as a soluble anode, and the copper collecting tank 9-2 is covered with a filter bag. The electrocatalytic cathode 6-3 is a conductor composed of a copper plate and copper wire coils. The first gas-liquid mixer 7-3 is a vacuum jet gas-liquid mixer made of polymer resin. It is equipped with an ultrasonic vibrating stirrer 40-2 for gas-liquid mixing and stirring. Its suction pipe is connected to an oxygen generator 59-3. The discharge port of the first gas-liquid mixer 7-3 is located below the electrocatalytic cathode 6-3. The electrocatalytic gas-liquid reaction tank 2-3 is equipped with a heat exchanger 34-3 and sensors 14-8, 14-9, 14-10, and 14-11. Sensors 14-8, 14-9, 14-10, and 14-11 are a thermometer, a photoelectric colorimeter, a dissolved oxygen meter, and an ultrasonic rangefinder, respectively. A copper fluxing electrolysis device 53 is installed in the space below the electrocatalytic cathode 6-3. The copper fluxing anode 54 is connected to both the positive terminal of the copper fluxing electrolysis power supply 53 and the electrocatalytic cathode 6-3. The copper fluxing cathode 55 is connected to the negative terminal of the copper fluxing electrolysis power supply 53 and is positioned in the lower middle part of the electrocatalytic gas-liquid reaction tank 2-3. A non-metallic perforated plate 57 separates the copper fluxing anode and cathode to prevent short circuits. Both the copper fluxing anode 54 and the copper fluxing cathode 55 are made of metallic copper.

[0213] The automatic detection and feeding controller 13 establishes a cascade control system for the electrocatalytic gas-liquid reaction tank 2-3, which simultaneously performs the first and second functions. The primary control system's reference input parameters are the copper source replenishment mode and electroplating current value in the electrocatalytic gas-liquid reaction tank itself. The controlled current value output by the electrocatalytic power supply 4-3 is obtained using the transfer function relationship of the primary system. The intermediate-level control system takes the primary output controlled parameters as its input parameters, simultaneously turns on the copper fluxing power supply, and adjusts its output current according to the process settings to dissolve the copper electroplated by the electrocatalytic cathode 6-3. Multiple output controlled parameter values ​​for sensors 14-9, 14-10, and 14-11 are obtained through the transfer function relationship of the intermediate level. Sensor 14-9 detects the current in the tank... If the concentration of divalent copper ions in the solution reaches the set value, the electrocatalytic power supply 4-3 will be shut down in the ongoing second functional mode. The copper fluxing anode 54 will then oxidize and dissolve the copper powder in the copper plating solution by colliding with it. The electrocatalytic power supply 4-3 will resume its original second functional state only after the detection value of sensor 14-9 is lower than the process set value. Sensor 14-10 is used as the input parameter of the final stage control system. The oxygen production is indirectly regulated by controlling the hydrogen peroxide dosing regulating valve, i.e., the oxidizing gas input regulator 35-3, in the oxygen generator 59-3 using the transfer function relationship of the final stage.

[0214] The electrocatalytic gas-liquid reaction tank 2-4 only has the first function mentioned above, that is, it only reduces the monovalent copper compounds and copper powder produced by the disproportionation reaction in the copper plating solution, and oxidizes and regenerates the divalent iron ions in the copper plating solution. The electrocatalytic gas-liquid reaction tank 2-4 uses two reverse osmosis membranes as separators 22-1 and 22-2 to divide the electrocatalytic gas-liquid reaction tank 2-4 into a three-part structure with one electrocatalytic cathode tank on each side and one electrocatalytic anode tank in the middle. The electrocatalytic anode tank has an overflow port 51. Sensors 14-13 and 14-14, respectively, are installed in the other two electrocatalytic cathode tanks, both of which are dissolved oxygen meters. The electrocatalytic anode 5-4 and electrocatalytic cathodes 6-4-1 and 6-4-2 are all electrodes made of titanium-based coated multilayer sheets. The first gas-liquid mixers 7-4-1 and 7-4-2 are bubbling gas-liquid mixers and are connected to the gas booster pump 36 via gas pipes. The outlets of the first gas-liquid mixers 7-4-1 and 7-4-2 are respectively equipped with microporous filter tubes 49-1 and 49-2, which are located at the bottom of their respective electrocatalytic cathodes 6-4-1 and 6-4-2.

[0215] The automatic detection and feeding controller 13 establishes a cascade control system for the electrocatalytic gas-liquid reaction tank 2-4, which only has the first function. The primary control system uses the copper plating solution replenishment mode in the electrocatalytic gas-liquid reaction tank as its reference input parameter. The primary output controlled parameter is obtained from the voltage value output by the electrocatalytic power supply 4-4 according to the transfer function relationship of the primary control system. The output operating voltage of the electrocatalytic power supply 4-4, the primary output controlled parameter, is taken as the input parameter of the intermediate control system. The output controlled parameters of sensors 14-13 and 14-14 are obtained according to the transfer function relationship of the intermediate level. The output controlled parameter of the intermediate control system is taken as the input parameter of the final stage. The ozone output is controlled by the high-voltage electric field voltage regulating valve of the ozone generator, i.e., the oxidizing gas input regulator 35-4, through the transfer function relationship of the final stage.

[0216] The electrocatalytic gas-liquid reaction tank 2-1 is connected to the electroplating tank 1 via a constant flow pump 28-11 pipe, an electroplating tank outlet pipe 30-1, and a solution flow power device 33-1 with high potential energy to form an independent liquid circulation pipeline. It is specifically used to reduce the copper powder produced by the monovalent copper compound and / or disproportionation reaction in the copper plating solution of the electroplating tank. The outlet of the solution flow power device 33-1 is located at the bottom of the electroplating tank 1, and its inlet is connected to the high-level overflow port of the electrocatalytic gas-liquid reaction tank 2-1 to form high potential energy as the flow power. The electrocatalytic gas-liquid reaction tank 2-2, controlled by the photoelectric colorimeter (sensor 14-2), activates the solution power unit 33-2 to add a high-copper-ion-concentration copper plating solution 25 to the electroplating tank. The solution overflowing from the electroplating tank 1 into the overflow buffer tank 11-1 is pumped to the electrocatalytic gas-liquid reaction tank 2-2 for electrolytic copper dissolution. The overflow from tank 2-2 then enters the electrocatalytic gas-liquid reaction tank 2-3 to continue the copper dissolution reaction, rapidly raising the copper ion concentration of the treated copper plating solution to the process-set concentration. The overflow from the electrocatalytic gas-liquid reaction tank 2-3 enters the electrocatalytic gas-liquid reaction tank 2-4 to reduce copper powder in the high-copper-ion-concentration copper plating solution overflowing from the previous tank. After copper powder reduction, the solution passes through the overflow buffer tank 11-5 and, after solid-liquid separation, is diverted to the temporary storage tank 29 for temporary storage. During this process, according to process requirements, it is returned to the electroplating tank 1 via the solution flow power unit 33-2 to continue participating in the electroplating reaction. To maintain the stability of the cathode electrolyte in the electrocatalytic gas-liquid reaction tank 2-4, a portion of the solution in the overflow buffer tank 11-5 is drawn into the two electrocatalytic cathode tanks of the electrocatalytic gas-liquid reaction tank 2-4 according to a time-controlled process. The overflow liquid from the two electrocatalytic cathode tanks of the electrocatalytic gas-liquid reaction tank 2-4 is then drained back into the electrocatalytic anode tank of the electrocatalytic gas-liquid reaction tank 2-4. The temporary storage tank 29 is equipped with a temperature exchanger 34-4 and sensors 14-15, 14-16, and 14-17, which are an ORP meter, a thermometer, and a chemical titration pH meter, respectively. The pH meter is used to control the addition of external sulfuric acid.

[0217] The inlet of the electroplating tank outlet pipe 30-1 is located near the cathode workpiece to draw in the copper plating solution containing a large amount of monovalent copper compounds and / or copper powder generated after disproportionation reaction for processing, and is connected to the electrocatalytic gas-liquid reaction tank inlet pipe 32-1 of the electrocatalytic gas-liquid reaction tank 2-1. The electroplating tank return pipe 31-1 is connected to the high-level overflow port of the electrocatalytic gas-liquid reaction tank 2-1, and the electroplating tank return pipe 31-2 is connected to the temporary storage tank 29 through the solution flow power device 33-2. The solutions flowing out of the outlets of the electroplating tank return pipes 31-1 and 31-2 are both sprayed toward the cathode workpiece. The electroplating tank outlet pipe 30-2 is connected to the electrocatalytic gas-liquid reaction tank inlet pipe 32-2 of the electrocatalytic gas-liquid reaction tank 2-2 via the overflow buffer tank 11-1. The outlet of the electrocatalytic gas-liquid reaction tank inlet pipe 32-2 is located in the space between the anode and cathode electrodes of the electrocatalytic gas-liquid reaction tank 2-2. The overflow port of the electrocatalytic gas-liquid reaction tank 2-2 is connected to the electrocatalytic gas-liquid reaction tank inlet pipes 32-3 and 32-4 of the electrocatalytic gas-liquid reaction tank 2-3 via the overflow buffer tank 11-2. A sensor 14-7 is installed in the overflow buffer tank 11-2. The overflow pipe of the electrocatalytic gas-liquid reaction tank 2-3 is connected to the electrocatalytic gas-liquid reaction tank inlet pipe 32-5 of the electrocatalytic gas-liquid reaction tank 2-4 via the overflow buffer tank 11-3. A sensor 14-12 is installed in the overflow buffer tank 11-3. Regarding the electrocatalytic gas-liquid reaction tank 2-3, the liquid inlet pipe 32-3 and the liquid inlet pipe 32-4 of the electrocatalytic gas-liquid reaction tank are provided. The liquid outlet of the liquid inlet pipe 32-3 is located in the space between the electrocatalytic anode 5-3 and the electrocatalytic cathode 6-3. The liquid outlet of the liquid inlet pipe 32-4 is directly inserted into the conductive copper metal collection tank 9-2.

[0218] Each hot and cold temperature exchanger is used to adjust the temperature of the solution in the tank to 30°C, so that it meets safety and production requirements.

[0219] The copper plating solution feeder 52-1 is installed on the pipe connecting the overflow buffer tank outlet of the electrocatalytic cathode electrolyte in tank 2-4 to the inlet pipe 32-5 of tank 2-4. It is used to feed the cathode electrolyte from tank 2-4 into the anode tank area to maintain the original composition and concentration of the cathode electrolyte. The copper plating solution feeder 52-2 is installed on the overflow buffer tank 11-5 to feed the anode electrolyte from tank 2-4 into the two cathode tank areas to maintain the original composition of the cathode electrolyte.

[0220] The exhaust gas treatment tank 26 is used to treat the exhaust gas escaping from each tank in the device in an environmentally friendly manner, and multiple exhaust gas escaping pipes are connected to the air intake of the exhaust gas treatment tank 26 by means of pipes.

[0221] The acidic copper sulfate plating solution used in this embodiment mainly consists of 200 g / L sulfuric acid, 65 g / L copper sulfate, and 35.7 g / L ferric sulfate (i.e., an iron ion concentration of 10 g / L). Its electrolytic decomposition voltage is 0.54 V. The copper ion concentration in the high copper ion concentration plating solution is 30 g / L, and the copper ion concentration in the plating bath is 26 g / L.

[0222] The operation steps of the method for dissolving metallic copper using an electrocatalytic gas-liquid reaction tank in this embodiment are as follows:

[0223] 1. Add copper plating solution to electroplating tank 1, each electrocatalytic gas-liquid reaction tank and overflow buffer tank, add metallic copper to the metallic copper collection tank 9 in electrocatalytic gas-liquid reaction tanks 2-2 and 2-3, and put the cathode plated parts into electroplating tank 1.

[0224] 2. Turn on the power to enable the automatic detection and feeding controller to sample and process the field data through various sensors. Under normal circumstances, the controller issues instructions to make the device run automatically according to the pre-programmed instructions.

[0225] 3. Turn on all pumps to run each gas-liquid mixer, turn on the two oxygen generators, turn on the gas booster pump 36 and ozone generator 60 to supply oxidizing gas to each electrocatalytic gas-liquid reaction tank under adjustment and control, turn on each heat exchanger, start the tail gas treatment tank, and make the copper plating solution circulate under process control.

[0226] 4. The automatic detection and feeding controller 13 issues a command to turn on the electroplating power supply and adjust the electroplating current to 100A. It then leads the oxygen from the electroplating anode electrolysis to the electrocatalytic gas-liquid reaction tank 2-1. The electrocatalytic power supply 4-1 is turned on and the output voltage is adjusted to 0.9V. The electrocatalytic power supplies 4-2 and 4-3 are turned on and the output current of each electrocatalytic power supply is adjusted to 55A according to the electroplating current value. The output voltage of each power supply is 3.8V. The copper dissolution power supply 53 is turned on and the output voltage is adjusted to 1.2V and the current is 3.2A. Copper dissolution is performed on the copper dissolution anode 54 and the electrocatalytic cathode 6-3 to solve the problem of copper electrolysis at the electrocatalytic cathode.

[0227] 5. When the photoelectric colorimeters in electrocatalytic gas-liquid reaction tanks 2-2 and 2-3 reach the set value of copper ion concentration of 31 g / L, the current value output by the corresponding electrocatalytic power supply is adjusted to 40 A. After the photoelectric colorimeter detection value is lower than 29 g / L, the automatic detection feed controller 13 issues a command to restore the original output working current of the corresponding electrocatalytic power supply to 55 A.

[0228] 6. When the photoelectric colorimeter 14-2 in the electroplating tank detects that the copper ion concentration in the copper plating solution is lower than the process set value of 26 g / L, the solution flow power device 33-2 is activated to return the copper plating solution with high copper ion concentration to the electroplating tank to replenish copper ions. The solution overflowing from the electroplating tank is diverted to the electrocatalytic gas-liquid reaction tank 2-2 for treatment.

[0229] 7. The automatic detection and feeding controller 13 sends commands to close the electrocatalytic power supplies 4-1 and 4-4 respectively, and adjusts the output voltage of electrocatalytic power supply 4-1 to 0.9V to obtain an output current of 2.2A according to its own copper source replenishment mode in the electrocatalytic gas-liquid reaction tank, and adjusts the output voltage of electrocatalytic power supply 4-4 to 1.8V to obtain a total output current of 3.7A.

[0230] 8. Each electrocatalytic anode primarily undergoes an electrochemical dissolution reaction of metallic copper and an electrochemical oxidation reaction involving collisions with monovalent copper compounds and divalent iron. Simultaneously, in the copper plating solution within the electrocatalytic gas-liquid reaction tanks 2-1, 2-2, and 2-3, oxidizing gases oxidize metallic copper, monovalent copper compounds, and divalent iron, while ferric ions in each electrocatalytic gas-liquid reaction tank oxidize metallic copper and monovalent copper compounds. During the reaction process, the automatic feeding controller 13 indirectly or directly adjusts the oxidizing gas input regulator 35 based on the output voltage and / or current of each electrocatalytic power supply and / or the controlled parameters output by the sensor, ensuring that the input amount of oxidizing gas is sufficient for each electrocatalytic cathode to react with its respective oxidizing gas without electrodepositing copper.

[0231] 9. When the automatic detection and feeding controller 13 adjusts the electroplating current to 120A according to the process requirements, the electrocatalytic power supplies 4-2 and 4-3 automatically adjust the cascade control system of the electrocatalytic gas-liquid reaction tanks according to the change in electroplating current. The output current of the two electrocatalytic power supplies 4-2 and 4-3 is 72A and the output voltage is adjusted to 4.3V to meet the production balance between electroplating copper precipitation and electrolytic copper dissolution. At the same time, after adjusting the output current of the two electrocatalytic power supplies 4-2 and 4-3, the automatic detection and feeding controller 13 increases the input of oxidizing gas in the electrocatalytic gas-liquid reaction tanks 2-2 and 2-3 according to the transfer function relationship in the program. When the photoelectric colorimeters in the electrocatalytic gas-liquid reaction tanks 2-2 and 2-3 reach the set value of copper ion concentration of 31g / L, the current value output by the corresponding electrocatalytic power supply is adjusted to 40A. After the photoelectric colorimeter detection value is lower than 29g / L, the automatic detection and feeding controller 13 issues a command to restore the original working current of the corresponding electrocatalytic power supply to 72A.

[0232] 10. The exhaust gas escaping from each tank in the device is diverted to the tail gas treatment tank for environmental protection treatment.

[0233] 11. In the temporary storage tank, use a pH meter with chemical titration to test whether the acidity of the copper plating solution 25 with high copper ion concentration meets the process requirements. If it does not meet the requirements, add sulfuric acid to supplement it.

[0234] 12. When the electroplating set time of 36 minutes has elapsed, shut down the electroplating power supply, all electrocatalytic power supplies, copper fluxing power supply, multiple pumps, and hot and cold temperature exchangers, and remove the cathode plated part 47 to complete the electroplating operation.

[0235] The key features of this embodiment are: continuous reduction of monovalent copper compounds and copper powder produced by the disproportionation reaction using an independent electrocatalytic gas-liquid reaction tank 2-1; and the use of two electrocatalytic gas-liquid reaction tanks 2-2 and 2-3 for copper dissolution reactions to replenish the copper source in the copper plating solution. A copper-dissolving aid is installed in electrocatalytic gas-liquid reaction tank 2-3 to address the issue of copper electrodeposition at the electrocatalytic cathode. Electrocatalytic gas-liquid reaction tank 2-4 is used to oxidize and eliminate residual copper powder in the copper plating solution after copper source replenishment. Furthermore, because the copper plating solution contains ferric sulfate, its ferric ions promptly eliminate the monovalent copper ions continuously produced during the plating process.

[0236] Example 6

[0237] Figure 6 shows a schematic diagram of the apparatus for dissolving metallic copper in an acidic copper plating solution according to Embodiment 6. The apparatus includes an electroplating tank 1, an electrocatalytic gas-liquid reaction tank 2, an electroplating power supply 3, an electrocatalytic power supply 4, two first gas-liquid mixers 7, one second gas-liquid mixer 58, two overflow buffer tanks 11, a solid-liquid separator 12, an automatic detection and feeding controller 13, four sensors 14, a temporary storage tank 29, an electroplating tank outlet pipe 30, an electroplating tank return pipe 31, an electrocatalytic gas-liquid reaction tank inlet pipe 32, a solution flow power device 33, an oxidizing gas input regulator 35, a gas booster pump 36, multiple microporous filter tubes 49, a copper plating solution feeder 52, an oxidizing gas supply source (natural atmosphere) 62, and multiple valves and pumps.

[0238] The electroplating tank 1 used in this embodiment is a soluble phosphorus copper anode electroplating tank, which includes an electroplating power source 3, an electroplating anode 56 and a cathode plated part 47. The electroplating phosphorus copper anode is placed in a titanium basket. Sensors 14-1 and 14-2 are also placed in the tank, which are a photoelectric colorimeter and a level gauge, respectively.

[0239] The electrocatalytic gas-liquid reaction tank 2 is equipped with an electrocatalytic anode 5, electrocatalytic cathodes 6-1 and 6-2, a first gas-liquid mixer 7-1 and 7-2, a second gas-liquid mixer 58, and an electrocatalytic power supply 4. The electrocatalytic anode 5 is an insoluble anode assembly composed of multiple titanium-based coated sheets, and the electrocatalytic cathodes 6-1 and 6-2 are both made of multiple titanium metal sheets. The positive electrode of the electrocatalytic power supply 4 is electrically connected to the electrocatalytic anode 5, and its negative electrode is electrically connected to the electrocatalytic cathodes 6-1 and 6-2 respectively.

[0240] The electrocatalytic gas-liquid reaction tank 2 described above only has the first function mentioned earlier, namely, it only reduces the monovalent copper compounds and copper powder produced by the disproportionation reaction in the copper plating solution. A bipolar membrane is used as the electrolytic cell separator 22-1, and an anion exchange membrane is used as the electrolytic cell separator 22-2, dividing the electrocatalytic gas-liquid reaction tank 2 into a three-part electrolytic cell structure with one electrocatalytic cathode cell on each side and one electrocatalytic anode cell in the middle. The two electrocatalytic cathode cell areas are respectively equipped with first gas-liquid mixers 7-1 and 7-2. A second gas-liquid mixer 58 is installed in the electrocatalytic anode cell area to introduce oxidizing gas into the electrocatalytic anode cell area, oxidizing and eliminating conductive solids adhering to the electrolytic cell separators 22-1 and 22-2, thus preventing conductive solids from forming secondary electrodes and damaging the electrocatalytic gas-liquid reaction tank 2. The first gas-liquid mixer 7-1, the first gas-liquid mixer 7-2, and the second gas-liquid mixer 58 are all bubbling gas-liquid mixers, and the outlets of the three gas-liquid mixers are respectively equipped with microporous filter tubes 49-1, 49-2, and 49-3. Both electrocatalytic cathode tank areas are equipped with overflow ports that are connected to the inlet of overflow buffer tank 11-1. The outlet of overflow buffer tank 11-1 is connected to solid-liquid separator 12 and then to overflow buffer tank 11-2. The electrocatalytic anode tank area is equipped with an overflow port 51 that is connected to the inlet of overflow buffer tank 11-2. The outlet of overflow buffer tank 11-2 is connected to temporary storage tank 29 and copper plating solution feeder 52. The outlet of copper plating solution feeder 52 is connected to the inlet of the gas collection cover at the top of the two electrocatalytic cathode tank areas to maintain the stability of the solution composition in the two electrocatalytic cathode tank areas.

[0241] The two suction ports of the electroplating tank outlet pipe 30 are respectively located at the bottom of the titanium basket of the electroplating anode and the lower part of the cathode plating part 47, and their outlet ports are connected to the inlet pipe 32 of the electrocatalytic gas-liquid reaction tank. The outlet port of the inlet pipe 32 of the electrocatalytic gas-liquid reaction tank is located below the electrocatalytic anode. The electroplating tank return pipe 31 is connected to the temporary storage tank 29 through the solution flow power device 33, and the two spray ports of the electroplating tank return pipe 31 are located around the middle of the cathode plating part, spraying towards the cathode plating part.

[0242] Sensors 14-3 and 14-4 are located in the two electrocatalytic cathode areas of the electrocatalytic gas-liquid reaction tank 2, respectively. Both sensors 14-3 and 14-4 are dissolved oxygen meters used to detect the dissolved oxygen level of the electrocatalytic cathode electrolyte. When the dissolved oxygen level is lower than the set value, the regulator 35 increases the flow rate of oxidizing gas to the gas booster pump to participate in the reaction.

[0243] In addition to having a built-in device operation control program, the automatic detection and feeding controller 13 also establishes a cascade control system for the electrocatalytic gas-liquid reaction tank 2. The primary control system uses the first functional mode of the electrocatalytic gas-liquid reaction tank as the reference input parameter, and obtains the primary output controlled parameter as the voltage output value of the electrocatalytic power supply according to the primary transfer function relationship. The primary controlled parameter is used as the input parameter of the intermediate control system, and the measured values ​​of the intermediate controlled parameters—sensors 14-3 and 14-4—are obtained according to their transfer function relationship. The final control system takes the measured values ​​of the two sensors 14-3 and 14-4 as input parameters, and adjusts the frequency converter target of the controlled gas booster pump 36, namely the oxidizing gas input regulator 35, according to the transfer function relationship of the final control system to achieve the process objective.

[0244] The main components of the acidic copper sulfate plating solution used in this embodiment are 80 g / L sulfuric acid and 160 g / L copper sulfate, and its electrolytic decomposition voltage is 0.55V.

[0245] The oxidizing gas used is air 19.

[0246] The operation steps of the method for dissolving metallic copper using an electrocatalytic gas-liquid reaction tank in this embodiment are as follows:

[0247] 1. Add phosphor bronze balls 20 and place cathode plating parts 47 into electroplating tank 1, and add copper plating solution to electroplating tank 1, electrocatalytic gas-liquid reaction tank 2, two overflow buffer tanks and temporary storage tank 29. Turn on the power of the device to make the automatic detection and feeding controller 13 enter the working state.

[0248] 2. The automatic detection and feeding controller 13 controls the pump of the solution flow power equipment 33 to start, the gas booster pump 36 to start, and adjusts the three gas flow distribution valves 27-4, 27-5, and 27-6 to send air into the three bubbling gas-liquid mixers and spray it out from the three microporous filter tubes. The pump 28-1 is started in constant flow mode.

[0249] 3. Turn on the electroplating power supply and adjust it to an electroplating current of 100A to perform the electroplating operation. Turn on the electrocatalytic power supply and adjust its output voltage to the electrolytic decomposition voltage of 0.55V, with an electrolytic current of 260mA. This reduces the monovalent copper compounds and copper powder produced by the disproportionation reaction in the copper plating solution while protecting the additives from damage. During the process, sensor 14-2 controls the solution flow power device 33 to return the solution 24 from the temporary storage tank to the electroplating tank.

[0250] 4. Collision oxidation and dissolution reactions occur on the electrocatalytic anode 5 with copper powder and monovalent copper compounds; simultaneously, due to the presence of oxidizing bubbles in the electrocatalytic anode tank area, the oxidizing gas in the copper plating solution reacts with the copper powder and monovalent copper compounds hanging on the electrolytic cell separator and suspended in the copper plating solution; during the reaction, the automatic detection feeding controller adjusts the gas booster pump 36 according to the detection values ​​of sensors 14-3 and 14-4 based on the detection values, so that there is enough air to participate in the reaction. The air is refined and diffused into the electrolyte by multiple microporous filter tubes 49. The reduction reaction of oxidizing gas occurs on the electrocatalytic cathode 6, and copper is not allowed to be electrodeposited from the electrocatalytic cathode. During the process, in order to maintain the stability of the cathode electrolyte composition, the anode electrolyte is added to the cathode tank area.

[0251] 5. When the electroplating set time of 26 minutes has elapsed, turn off the electroplating power supply, electrocatalytic power supply, all pumps and gas booster pumps, and remove the cathode plated parts to complete the electroplating operation.

Claims

1. A method for dissolving metallic copper in an acidic copper plating solution, characterized in that, Includes the following steps: Step (1): Using an electrocatalytic gas-liquid reaction tank connected to the electroplating tank via a pipeline, a portion of the copper plating solution is taken from the electroplating tank in operation and diverted to the electrocatalytic gas-liquid reaction tank for electrocatalytic oxidation; the electrocatalytic gas-liquid reaction tank includes an electrocatalytic anode, an electrocatalytic cathode, an electrocatalytic power supply and a gas-liquid mixer, and the positive and negative terminals of the electrocatalytic power supply are connected to the electrocatalytic anode and the electrocatalytic cathode, respectively; Step (2): Turn on the electrocatalytic power supply and input oxidizing gas into the gas-liquid mixer in the electrocatalytic gas-liquid reaction tank. The oxidizing gas reacts electrochemically with the electrocatalytic cathode under electrocatalysis, and simultaneously reacts with cuprous chloride and / or metallic copper in the copper plating solution under acidic medium. In addition, the electrocatalytic anode also undergoes a contact-type electrochemical oxidation and dissolution reaction with cuprous chloride and / or metallic copper in the copper plating solution. The metallic copper in the copper plating solution is copper powder produced by the disproportionation reaction of monovalent copper ion compounds in the copper plating solution and / or metallic copper from outside the electroplating tank. Step (3): The entire reaction process of the reaction liquid in the electrocatalytic gas-liquid reaction tank is controlled by a cascade control system. The control target of the final control system is adjusted by referring to the input parameters from the primary control system through the inter-level transfer function relationship. Specifically, the value of the electroplating current or the change in the electroplating current combined with the copper source replenishment mode of the copper plating solution selected in the electrocatalytic gas-liquid reaction tank is used as the reference input parameter of the primary control system in the cascade control system, and the primary output controlled parameter is obtained according to the primary transfer function relationship, which is the voltage or current value output by the electrocatalytic power supply. The primary output controlled parameter is used as the input parameter of the final stage control system. The transfer function relationship of the final stage control system is used to regulate the amount of controlled target oxidizing gas input in the final stage output, so as to achieve the goal of preventing copper electrodeposition at the electrocatalytic cathode during the reaction process or maintaining the rate of copper electrodeposition at the cathode within the range allowed by the process in a cascade control manner. Step (4): The copper plating solution that has been electrocatalytically oxidized and dissolved in the electrocatalytic gas-liquid reaction tank is returned to the electroplating tank to continue participating in the electroplating reaction according to the process requirements.

2. The method for dissolving metallic copper in an acidic copper plating solution according to claim 1, characterized in that, In step (1), at least one parameter that affects the concentration of divalent copper ions and / or the total amount of cuprous chloride and copper powder in the electroplating tank during the electroplating process is used as the controlled object to control the flow of the copper plating solution in the electroplating tank to the electrocatalytic gas-liquid reaction tank in an intermittent or continuous extraction manner; the parameters that cause and reflect the change in the concentration of divalent copper ions in the copper plating solution in the electroplating tank include the electroplating time, electroplating current density, solution level in the electroplating tank, as well as the color, acidity and redox potential value of the copper plating solution.

3. The method for dissolving metallic copper in an acidic copper plating solution according to claim 2, characterized in that, The oxidizing gas is ozone and / or oxygen and / or air; branch conductors are added to the electrocatalytic anode and / or electrocatalytic cathode in terms of structure; wherein, the branch conductors on the electrocatalytic anode are made of the same material as the electrocatalytic anode or other insoluble anode materials, and the branch conductors on the electrocatalytic cathode are made of metallic copper.

4. The method for dissolving metallic copper in an acidic copper plating solution according to claim 3, characterized in that, When the electrocatalytic anode is an insoluble anode, that is, there is no metallic copper from outside the electroplating tank in the electrocatalytic gas-liquid reaction tank, the voltage value output by the electrocatalytic power supply is used as the input parameter of the final stage control system in the control system, and the final stage output parameter value of the controlled target oxidizing gas input is controlled by the transfer function relationship. Furthermore, the output voltage range of the electrocatalytic power supply is controlled to be 0.34–24V.

5. The method for dissolving metallic copper in an acidic copper plating solution according to claim 4, characterized in that, When the electrocatalytic anode is an insoluble anode, the output voltage of the electrocatalytic power supply is adjusted to the electrolytic decomposition voltage value or a positive deviation voltage value is added to its target electrolytic decomposition voltage value for electrolysis operation; the electrolytic decomposition voltage value of the copper plating solution in the electrocatalytic gas-liquid reaction tank refers to the result of the voltage difference applied between the electrocatalytic anode and cathode when the output voltage of the electrocatalytic power supply is adjusted on site, causing the insoluble anode to just begin to electrodeposit oxygen bubbles in the copper plating solution, and the voltage output of the electrocatalytic power supply at this critical point is defined as the electrolytic decomposition voltage value of the copper plating solution in the electrocatalytic gas-liquid reaction tank; The positive deviation voltage value is the difference between the actual operating voltage value and the target value of the electrolytic decomposition voltage, and its range is from 0 to the upper limit of the positive deviation. The upper limit refers to the voltage point at which the voltage output by the electrocatalytic power supply can cause the electrolyte in the electrocatalytic gas-liquid reaction tank to electrolyze and generate chlorine-oxygen free radicals, which in turn cause significant damage to the additives in the copper plating solution. The difference between this voltage point and the electrolytic decomposition voltage value is the upper limit of the positive deviation.

6. The method for dissolving metallic copper in an acidic copper plating solution according to claim 3, characterized in that, When the electrocatalytic anode includes a soluble copper anode, meaning there is copper from outside the electroplating tank in the electrocatalytic gas-liquid reaction tank, the output current of the electrocatalytic power supply is adjusted during copper source replenishment according to Faraday's law of electrolysis. This causes the electrochemical reaction of copper oxidation and dissolution to primarily occur at the electrocatalytic anode. The output current of the electrocatalytic power supply is used as the input parameter of the final-stage control system to control the amount of oxidizing gas introduced, achieving the process objective of dissolving copper from outside the electroplating tank. During this copper source replenishment process, and when the electrocatalytic anode... Once the copper ion concentration in the nearby electrolyte reaches the process set value, the electrocatalytic power supply is required to operate in at least one of the following three modes to balance the rate of copper electrolysis in the electroplating tank and the rate of copper oxidation and dissolution in the electrocatalytic gas-liquid reaction tank: ① using an intermittent on-off power supply mode; ② using a mode that switches between the normal copper dissolution current density of the electrocatalytic power supply and the current voltage value near the electrolytic decomposition voltage value; ③ using a mode that switches between the output current density of the electrocatalytic power supply being greater than, equal to, or less than the electroplating current density, based on the electroplating current density.

7. The method for dissolving metallic copper in an acidic copper plating solution according to claim 3, characterized in that, Measures such as increasing the temperature of the electrolyte in the electrocatalytic gas-liquid reaction tank and / or spraying the gas-liquid mixed electrolyte of oxidizing gas toward the electrocatalytic cathode are taken to promote the electrochemical reaction between the electrocatalytic cathode and the oxidizing gas.

8. The method for dissolving metallic copper in an acidic copper plating solution according to claim 3, characterized in that, After the electrolyte containing oxidizing bubbles has reacted at the electrocatalytic cathode, the remaining liquid flow containing a small amount of oxidizing bubbles is diverted to the electrolytic anode. This allows the copper powder electrolyzed from the original cathode electrolyte to react with the oxidizing gas and dissolve in the acid solution and / or to collide with the electrocatalytic anode for dissolution. Alternatively, this oxidizing bubble liquid flow can be diverted to the soluble metallic copper anode to participate in the metallic copper dissolution reaction at the electrocatalytic anode. This eliminates the trace amount of sponge copper electrolyzed at the electrocatalytic cathode while utilizing the remaining small amount of oxidizing gas in the bubble solution to oxidize the metallic copper anode.

9. The method for dissolving metallic copper in an acidic copper plating solution according to claim 3, characterized in that, An electrolytic cell separator is added to the electrocatalytic gas-liquid reaction tank to divide the electrocatalytic gas-liquid reaction tank into an electrocatalytic anode tank area and an electrocatalytic cathode tank area. The outlet of the gas-liquid mixer is located in the electrocatalytic cathode tank area. The electrolytic cell separator is either a separator that allows the solution to pass through but effectively prevents solids and bubbles in the electrolyte from passing through, or a membrane that only allows ions in the solution between the two tank areas to pass through while effectively preventing the electrolyte, its solids, and bubbles from passing through.

10. The method for dissolving metallic copper in an acidic copper plating solution according to claim 9, characterized in that, When the electrocatalytic anode includes a soluble metallic copper anode, and the copper ion concentration of the anolyte in the electrocatalytic gas-liquid reaction tank meets the process requirements, the electrocatalytic power supply is shut down or its output voltage is adjusted to be equal to or less than 0.34V. The supply of oxidizing gas to the electrocatalytic cathode tank area is extended to allow the copper already electrodeposited on the electrocatalytic cathode to undergo an oxidation reaction and dissolve in sulfuric acid. Alternatively, the current density output by the electrocatalytic power supply is reduced to slow down the original copper dissolution rate in the copper source replenishment. At this time, the same amount of oxidizing gas input before the adjustment is maintained, so that the copper electrolyzed on the electrocatalytic cathode before the adjustment is oxidized and dissolved at this time, so that the copper dissolved at the anode and the copper on the cathode maintain the original equilibrium point.

11. The method for dissolving metallic copper in an acidic copper plating solution according to claim 3, characterized in that, When the electrocatalytic anode includes a soluble copper anode, a copper-solubilizing electrolysis device is added to immediately dissolve the copper electrolyzed by the electrocatalytic cathode. The copper-solubilizing electrolysis device includes a copper-solubilizing electrolysis power supply, a copper-solubilizing anode, and a copper-solubilizing cathode. Both the copper-solubilizing anode and the copper-solubilizing cathode are located in the space near the electrocatalytic cathode within the electrocatalytic gas-liquid reaction tank. Both the electrocatalytic cathode and the copper-solubilizing anode are made of copper and are electrically connected. The copper-solubilizing anode is connected to the positive terminal of the copper-solubilizing electrolysis power supply, and the copper-solubilizing cathode is connected to the negative terminal of the copper-solubilizing electrolysis power supply. The copper-solubilizing cathode is placed independently next to the electrocatalytic cathode and undergoes an electrocatalytic reaction with the oxidizing gas.

12. The method for dissolving metallic copper in an acidic copper plating solution according to claim 3, characterized in that, Sensors and automatic detection and feeding controllers are used to perform on-site sampling, detection, data processing, and monitoring of the entire production unit. The sensors are selected from at least one of the following: pH meter, specific gravity meter, photoelectric colorimeter, pH meter, redox potentiometer, galvanometer, level gauge, thermometer, gas flow meter, weighing meter, conductivity meter, dissolved oxygen meter, liquid flow meter, liquid pressure gauge, and ultrasonic detector. The sensors, namely pH meter, photoelectric colorimeter, specific gravity meter, redox potentiometer, galvanometer, dissolved oxygen meter, and weighing meter, are installed in the electrocatalytic gas-liquid reaction tank to monitor multiple process parameters related to the weight change of the electrolyte or electrolytic cathode. At least one of the on-site process parameters measured by the installed sensors is used as the reference input parameter of the final control system in the cascade control system of the electrocatalytic gas-liquid reaction tank, and the output of the final control system is fed back to control the amount of oxidizing gas fed into the final control system according to its transfer function relationship.

13. The method for dissolving metallic copper in an acidic copper plating solution according to claim 3, characterized in that, An ultrasonic vibrating stirrer is used to stir the gas-liquid mixture in the electrocatalytic gas-liquid reaction tank and to disperse and refine the bubbles in the electrolyte.

14. An apparatus for dissolving metallic copper in an acidic copper plating solution using the method of claim 1, characterized in that, It includes an electroplating tank, an electrocatalytic gas-liquid reaction tank, an electroplating tank outflow pipe, an electroplating tank return pipe, an electrocatalytic gas-liquid reaction tank inflow pipe, a solution flow power device, an oxidizing gas input regulator, an oxidizing gas supply source, and an automatic detection and feeding controller. During operation, the device establishes a liquid circulation loop between the electroplating tank and the electrocatalytic gas-liquid reaction tank. A device operation control system is established within the device, which comprises the electroplating tank, the electrocatalytic gas-liquid reaction tank, the oxidizing gas supply source, and the oxidizing gas input regulator. A cascade control system within the electrocatalytic gas-liquid reaction tank controls the gas-liquid reaction process. The primary control system of the cascade control system selects the copper source replenishment process mode parameters of the electrocatalytic gas-liquid reaction tank, as well as the electroplating current value and / or the change in electroplating current, as reference input parameters. Based on the primary transfer function relationship, the primary control system outputs the controlled parameters, i.e., the voltage and / or current values ​​output by the electrocatalytic power supply. These primary output controlled parameters are used as input parameters for the final control system. After processing using the final control system's transfer function relationship, the final output controlled target oxidizing gas input amount is obtained, and the oxidizing gas input regulator controls the actual amount of oxidizing gas input. The electrocatalytic gas-liquid reaction tank is equipped with an electrocatalytic anode, an electrocatalytic cathode, a first gas-liquid mixer, and an electrocatalytic power supply with output adjustment. The positive terminal of the electrocatalytic power supply is connected to the electrocatalytic anode, and the negative terminal is connected to the electrocatalytic cathode. The electrocatalytic anode is an insoluble anode assembly, or a soluble copper anode loaded in a copper collection tank, or a combination of an insoluble anode assembly and a soluble copper anode loaded in a copper collection tank. The gas delivery pipe of the oxidizing gas supply source is connected to the first gas-liquid mixer. The electroplating tank outflow pipe is a liquid flow pipe that draws part of the copper plating solution from the electroplating tank to the electrocatalytic gas-liquid reaction tank. One end of the pipe is connected to the liquid outlet of the electroplating tank or placed in the electroplating tank, and the other end of the pipe is connected to the liquid inlet pipe of the electrocatalytic gas-liquid reaction tank or connected to the tank into which the solution flows into the liquid inlet pipe of the electrocatalytic gas-liquid reaction tank. The electroplating tank return pipe is a pipe that returns the copper plating solution that has undergone electrocatalytic oxidation treatment to the electroplating tank. One end of the pipe is connected to the inlet of the electroplating tank or placed in the electroplating tank, and the other end of the pipe is connected to the outlet of the electrocatalytic gas-liquid reaction tank through the pipe of the solution flow power equipment, or connected to the pipe of the tank containing the copper plating solution that has undergone electrocatalytic oxidation treatment through the solution flow power equipment. The solution flow power device is located on the connecting pipe between the electroplating tank return pipe and the outlet pipe of the electrocatalytic gas-liquid reaction tank. It is a power device that draws the electrocatalytically oxidized copper plating solution back from the electrocatalytic gas-liquid reaction tank to the electroplating tank. The solution flow power device is specifically a pump and / or a tank with high liquid flow potential energy. When a pump is used as the solution flow power device, its inlet is connected to the outlet pipe of the electrocatalytic gas-liquid reaction tank, and its outlet pipe is connected to the inlet pipe of the electroplating tank return pipe; or its inlet is connected to the outlet pipe of the tank containing the electrocatalytically oxidized copper plating solution, and its outlet pipe is still connected to the inlet pipe of the electroplating tank return pipe; when a tank with high liquid flow potential energy is used as the solution flow power device, the high potential energy tank is a tank containing the electrocatalytically oxidized copper plating solution, and its outlet pipe is connected to the inlet pipe of the electroplating tank return pipe. The inlet of the liquid inlet pipe of the electrocatalytic gas-liquid reaction tank is connected to the outlet pipe of the electroplating tank, or connected to the outlet pipe of the tank containing the liquid flowing out of the electroplating tank, with the outlet located inside the electrocatalytic gas-liquid reaction tank.

15. The apparatus for dissolving metallic copper in an acidic copper plating solution according to claim 14, characterized in that, The oxidizing gas supply source is the natural atmosphere, an oxygen generator, an ozone generator, and an oxidizing gas storage device. The oxygen generator is an electrolytic oxygen generator and / or a chemical oxygen generator. The oxidizing gas input rate regulator adjusts the gas input flow rate according to the output parameters of the electrocatalytic power supply. The oxidizing gas input rate regulator can be installed in at least one of the following ways: ① installed on the output pipe of a high-pressure container storing oxidizing gas, adjusting the gas flow rate via valve operation; ② installed on a gas booster pump providing a pressure difference in a bubbling-type first gas-liquid mixer, controlling the increase or decrease in the oxidizing gas input rate by adjusting the speed of the pump's moving parts; ③ installed on a variable frequency pump in a vacuum jet-type first gas-liquid mixer, using variable frequency speed control. Adjust the flow rate of oxidizing gas drawn in by the vacuum jet under negative pressure, or use a pipe gate regulator installed on the vacuum jet's negative pressure intake pipe to adjust the size and thus change the amount of oxidizing gas drawn in by the vacuum jet; ④ Install it on the electrolysis power supply of the electrolysis oxygen generator to regulate the electrolysis current and control the oxygen output; ⑤ Install it on the chemical oxygen generator to control the speed of the raw material feeder or the amount of raw material fed in to regulate and control the oxygen output; ⑥ Install it on the ozone generator to adjust the ionization voltage and / or oxygen supply, thereby controlling the amount of ozone produced for the reaction.

16. The apparatus for dissolving metallic copper in an acidic copper plating solution according to claim 14, characterized in that, The first gas-liquid mixer is a bubbling gas-liquid mixer and / or a vacuum jet gas-liquid mixer, which is equipped with an air inlet and / or an air inlet pipe to introduce oxidizing gas in the form of positive or negative pressure to mix with copper plating liquid to form a gas-liquid mixture reactant for chemical reaction in the electrocatalytic gas-liquid reaction tank; the outlet of the first gas-liquid mixer faces the electrocatalytic cathode or is placed near the electrocatalytic cathode.

17. The apparatus for dissolving metallic copper in an acidic copper plating solution according to claim 14, characterized in that, Sensors are added to at least one container and / or at least one pipeline and / or each electrocatalytic gas-liquid reaction tank in the device's operation control system, and an automatic detection and feeding controller is used to sample and process on-site data of the device to ensure that the device operates according to process requirements; the sensors include at least one selected from acidity meter, hydrometer, photoelectric colorimeter, pH meter, redox potentiometer, dissolved oxygen meter, electrocoupled copper ion concentration meter, level meter, turbidity meter, thermometer, gas flow meter, liquid flow meter, liquid pressure gauge, weighing meter, and ultrasonic detector; and when the electrocatalytic anode is a soluble copper anode loaded in a copper collection tank or a combination of an insoluble anode assembly and a soluble copper anode loaded in a copper collection tank, a hydrometer and / or photoelectric colorimeter and / or acidity meter and / or conductivity meter and / or electrocoupled copper ion concentration meter are installed in the electrocatalytic gas-liquid reaction tank to detect the copper ion concentration in the electrolyte near the electrocatalytic anode.

18. The apparatus for dissolving metallic copper in an acidic copper plating solution according to claim 14, characterized in that, The electrocatalytic cathode is placed above the outlet of the first gas-liquid mixer and / or downstream of the liquid flow containing oxidizing bubbles; the electrocatalytic anode is placed in the path of the liquid flow coming from the direction of the electrocatalytic cathode, and the electrocatalytic anode is used to intercept cuprous chloride and / or copper powder in the liquid flow for oxidation and dissolution reaction.

19. The apparatus for dissolving metallic copper in an acidic copper plating solution according to claim 14, characterized in that, Orient the outlet of the liquid inlet pipe of the electrocatalytic gas-liquid reaction tank toward the electrocatalytic anode.

20. The apparatus for dissolving metallic copper in an acidic copper plating solution according to claim 14, characterized in that, A bubble collector is added to the electrocatalytic cathode tank area to collect the residual oxidizing gas that has not participated in the reaction. The gas is then returned to the area below or near the electrocatalytic cathode by a liquid circulation stirrer in the electrocatalytic cathode tank area and continues to participate in the electrochemical reaction of the electrocatalytic cathode, so that the oxidizing gas material can be fully utilized. The feed hood of the bubble collector is placed above the electrocatalytic cathode, and its outlet is connected to the electrocatalytic cathode tank area through a liquid circulation stirrer.

21. The apparatus for dissolving metallic copper in an acidic copper plating solution according to claim 14, characterized in that, An electrolytic cell separator is added to the electrocatalytic gas-liquid reaction tank to divide it into an electrocatalytic anode tank area and an electrocatalytic cathode tank area. The electrolytic cell separator is of one or more types: the first type is selected from one or more separators selected from filter membranes, filter cloths, polymer resin microporous plates, ceramic filter plates, etc., which allow the electrolyte to pass through and effectively prevent the passage of solids and bubbles; the second type is selected from one or more separators selected from bipolar membranes, cation exchange membranes, anion exchange membranes, reverse osmosis membranes, etc., which allow the passage of ions in the electrolyte to pass through and effectively prevent the passage of solids and bubbles.

22. The apparatus for dissolving metallic copper in an acidic copper plating solution according to claim 14, characterized in that, A copper-coating electrolysis device is added to the electrocatalytic gas-liquid reaction tank. The copper-coating electrolysis device includes a copper-coating electrolysis power supply, a copper-coating anode, and a copper-coating cathode. The copper-coating anode and the copper-coating cathode are both located in the space near the electrocatalytic cathode of the electrocatalytic gas-liquid reaction tank. Both the electrocatalytic cathode and the copper-coating anode are made of metallic copper and are electrically connected. The copper-coating anode is connected to the positive terminal of the copper-coating electrolysis power supply, and the copper-coating cathode is connected to the negative terminal of the copper-coating electrolysis power supply. The copper-coating cathode is placed independently next to the electrocatalytic cathode and plays an additional role in the electrocatalytic reaction of oxidizing gases to improve the reaction efficiency.

23. The apparatus for dissolving metallic copper in an acidic copper plating solution according to claim 22, characterized in that, When installing a copper electrolysis device to assist in dissolving the electrolyte in an electrocatalytic gas-liquid reaction tank, select the type of sensor to install according to the following control methods: ① Add a weighing meter to the electrocatalytic cathode; ② Add at least one of the following at the following locations: near the electrocatalytic cathode, in the electrocatalytic cathode tank area, in the pipes connecting the electrocatalytic cathode tank area, or in the container containing the overflow liquid of the electrocatalytic cathode electrolyte; adjust the operating current of the electrocatalytic power supply and / or the copper electrolysis power supply according to the detection data of the above sensors, so as to solve the problem of copper electrodeposition at the electrocatalytic cathode through feedback control.

24. The apparatus for dissolving metallic copper in an acidic copper plating solution according to claim 21, characterized in that, A second gas-liquid mixer is added to the electrocatalytic anode tank area. At this time, the outlet of the first gas-liquid mixer is placed in the electrocatalytic cathode tank area. The outlet of the second gas-liquid mixer is installed at the lower part of the electrocatalytic anode tank area or near the electrolytic cell separator. The second gas-liquid mixer is used to introduce oxidizing gas into the electrocatalytic anode tank area to oxidize and dissolve cuprous chloride from the copper plating solution, copper powder produced by the disproportionation reaction, and copper powder produced from the soluble metallic copper anode in the electrocatalytic anode tank area in a sulfuric acid solution containing oxidizing bubbles.

25. The apparatus for dissolving metallic copper in an acidic copper plating solution according to claim 24, characterized in that, A bubble disperser or microporous filter tube is connected to the outlet of the first or second gas-liquid mixer to refine and disperse the bubbles flowing from the gas-liquid mixer into the liquid, so that they can participate in the reaction better.

26. The apparatus for dissolving metallic copper in an acidic copper plating solution according to claim 14, characterized in that, For electroplating tanks using insoluble anodic electroplating, the outlet of the return pipe of the electroplating tank is located near the cathode workpiece, and the copper plating solution is sprayed onto the cathode workpiece without affecting the electroplating quality; the inlet of the outlet pipe of the electroplating tank is located near the cathode workpiece. For electroplating tanks using soluble anodic electroplating, the inlet of the outlet pipe of the electroplating tank is located near the soluble anode of the electroplating tank and / or inside the titanium basket and / or inside the titanium basket filter bag.

Images