Ionic membrane experiment electrolysis device

Abstract

The invention is suitable for the technical field of copper recovery through electrolysis of PCB etching waste liquid, and provides an ionic membrane experiment electrolysis device which comprises a negative electrode liquid supply unit, an electrolysis unit, an etching unit and a tail gas treatment unit. The etching unit comprises an etching cylinder; the negative electrode liquid supply unit comprises a negative electrode transfer cylinder; the electrolysis unit comprises an electrolysis cylinder, and an ionic membrane positive electrode groove is formed in the electrolysis cylinder; the etching cylinder inputs positive electrode liquid into the ionic membrane positive electrode groove through a pipeline, and the ionic membrane positive electrode groove enables the positive electrode liquid to flow back to the etching cylinder; the negative electrode transfer cylinder inputs negative electrode liquid into the electrolysis cylinder, and the negative electrode liquid in the electrolysis cylinder overflows back to the negative electrode transfer cylinder; and waste gas of the electrolysis cylinder is absorbed and treated through the tail gas treatment unit. According to the ionic membrane experimental electrolysis device, the positive electrode groove and the negative electrode groove are separated through the ionic membrane, the positive electrode groove and the etching cylinder are circulated, the problem that a large amount of chlorine is generated in the positive electrode groove is solved, chlorine generation is reduced, and the chlorine treatment cost is saved.

Description

Technical Field

[0001] The present invention belongs to the technical field of electrolytic recovery of copper from PCB etching waste liquid, and particularly relates to an ion membrane experimental electrolysis device. Background Art

[0002] A PCB (Printed Circuit Board) is a basic component in electronic devices for mechanically supporting and electrically connecting electronic components. It is composed of a non-conductive substrate (usually fiberglass or similar materials), and conductive paths (usually made of copper) are printed or etched on its surface. PCBs play a crucial role in modern electronic devices.

[0003] The PCB production process requires an etching process. The PCB etching process is a key process in the manufacturing of printed circuit boards (PCBs), mainly used to form circuit patterns on the conductive layer. Its basic principle is to remove the unprotected copper layer through a chemical reaction, leaving only the required circuit lines.

[0004] The PCB etching process requires a large amount of etching solution stock solution, and at the same time, a large amount of etching waste liquid will be generated. The main components of the commonly used acidic etching solution stock solution are copper chloride, concentrated hydrochloric acid, hydrogen peroxide, water and other components. In the etching waste liquid generated after PCB etching, according to the chemical formula, Cu + H 2 O 2 + 2HCl = CuCl 2 + 2H 2 O, which contains a large amount of copper with relatively high economic value. During the process of electrolytic recovery of copper, chlorine gas will be generated; chlorine gas is toxic and easily threatens the physical health of workers. Therefore, during the electrolysis process, generally, an exhaust pipe will discharge the chlorine gas into an alkaline solution, so that the chlorine gas and the alkaline solution react fully, thereby achieving the effect of tail gas treatment. Due to the large amount of chlorine gas to be treated, the cost of the alkaline solution is too high.

[0005] Based on the above defects, the present invention proposes an ion membrane experimental electrolysis device. Summary of the Invention

[0006] The object of the present invention is to provide an ion membrane experimental electrolysis device to solve the problem that in the prior art, during the electrolytic recovery of copper from PCB etching waste liquid, generally, an exhaust pipe discharges chlorine gas into an alkaline solution, so that the chlorine gas and the alkaline solution react fully, and due to the large amount of chlorine gas to be treated, the cost of the alkaline solution is too high.

[0007] To achieve the above object, the present invention provides the following technical solution: an ion membrane experimental electrolysis device, including a negative electrode liquid supply unit, an electrolysis unit, an etching unit and a tail gas treatment unit;

[0008] The etching unit includes an etching tank; the negative liquid supply unit includes a negative intermediate tank; the electrolysis unit includes an electrolysis tank, and an ion membrane positive electrode tank is provided inside the electrolysis tank;

[0009] The etching tank inputs positive electrode liquid into the ion membrane positive electrode tank through a pipeline, and the ion membrane positive electrode tank flows the positive electrode liquid back to the etching tank;

[0010] The negative intermediate tank inputs negative electrode liquid into the electrolysis tank, and the negative electrode liquid in the electrolysis tank overflows back to the negative intermediate tank;

[0011] The waste gas of the electrolysis tank is absorbed and treated by a tail gas treatment unit.

[0012] Preferably, the electrolysis unit includes three electrolysis tanks arranged side by side. A negative electrode liquid overflow pipe and a positive electrode liquid overflow pipe are arranged between the three electrolysis tanks. The electrolysis tank is provided with a negative electrode liquid overflow port and is connected to the negative electrode liquid overflow pipe. Four ion membrane positive electrode tanks are provided inside each electrolysis tank.

[0013] Preferably, an electrolysis positive electrode is placed in each ion membrane positive electrode tank, and an electrolysis negative electrode is placed between every two adjacent ion membrane positive electrode tanks.

[0014] Preferably, a positive electrode liquid delivery pump is connected to one side of the etching tank. The output end of the positive electrode liquid delivery pump is connected to a positive electrode liquid input main pipe. The positive electrode liquid input main pipe is connected to a plurality of positive electrode liquid input branch pipes, and the plurality of positive electrode liquid input branch pipes are respectively connected to each ion membrane positive electrode tank.

[0015] Preferably, the negative intermediate tank is connected to a negative liquid supply main pipe. The negative liquid supply main pipe is connected to a plurality of negative liquid supply branch pipes, and the plurality of negative liquid supply branch pipes are respectively connected to each electrolysis tank.

[0016] Preferably, each ion membrane positive electrode tank is connected to a positive electrode liquid output branch pipe. The positive electrode liquid output branch pipe is connected to a positive electrode liquid output main pipe. The positive electrode liquid output main pipe is connected to the etching tank.

[0017] Preferably, the tail gas treatment unit includes a tail gas treatment device. The tail gas treatment device is connected to an exhaust main pipe. The exhaust main pipe is connected to an exhaust branch pipe. The exhaust branch pipe is connected to the electrolysis tank.

[0018] Preferably, an acidic etching liquid is filled in the etching tank and the ion membrane positive electrode tank. The parameters of the acidic etching liquid are as follows:

[0019] Copper ions 120 - 140 g / L, chloride ions 270 - 290 g / L, acidity 1.2 - 2.5, ORP value controlled at 650 - 750 mv.

[0020] Preferably, the electrolysis cell and the negative electrode transfer tank are filled with acidic electrolyte, and the parameters of the acidic electrolyte are as follows:

[0021] Copper ions: 30 - 40 g / L, chloride ions: 180 - 230 g / L, acidity: 2.5 - 4.0.

[0022] Preferably, a stirrer is arranged through the top surface of the etching tank.

[0023] The present invention has at least the following beneficial effects:

[0024] The present invention provides an ion-exchange membrane experimental electrolysis device, which separates the positive electrode tank from the negative electrode tank with an ion-exchange membrane and circulates the positive electrode tank and the etching tank, solves the problem of a large amount of chlorine gas generated in the positive electrode tank, reduces the generation of chlorine gas, and saves the cost of treating chlorine gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0026] Figure 2 It is a schematic diagram of the specific structure of the negative electrode liquid supply unit and the tail gas treatment unit in the present invention;

[0027] Figure 3 It is a schematic diagram of the specific structure of the etching unit in the present invention;

[0028] Figure 4 It is a schematic diagram of the specific structure of the electrolysis unit in the present invention.

[0029] In the reference numerals of the drawings: 1. Negative electrode liquid supply unit; 2. Electrolysis unit; 3. Etching unit; 4. Tail gas treatment unit; 5. Negative electrode transfer tank; 6. Negative electrode liquid supply main pipe; 7. Negative electrode liquid supply branch pipe; 8. Exhaust branch pipe; 9. Exhaust main pipe; 10. Tail gas treatment device; 11. Positive electrode liquid delivery pump; 12. Etching tank; 13. Stirrer; 14. Positive electrode liquid input main pipe; 15. Positive electrode liquid input branch pipe; 16. Ion-exchange membrane positive electrode tank; 17. Electrolysis positive electrode; 18. Electrolysis negative electrode; 19. Positive electrode liquid output branch pipe; 20. Negative electrode liquid overflow port; 21. Negative electrode liquid overflow pipe; 22. Positive electrode liquid overflow pipe. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0031] Embodiment

[0032] Please refer to Figure 1 、 Figure 2 、 Figure 3 and Figure 4 ,the present invention provides a technical solution: an ion membrane experimental electrolysis device, comprising a negative electrode liquid supply unit 1, an electrolysis unit 2, an etching unit 3 and a tail gas treatment unit 4; the etching unit 3 includes an etching tank 12, and a stirrer 13 is inserted through the top cover plate of the etching tank 12. Specifically, the stirrer 13 includes a motor, the motor is arranged on the top cover plate of the etching tank 12, the output shaft of the motor penetrates through the top cover plate of the etching tank 12 and extends into the interior of the etching tank 12, and is connected with a stirring rod, and the output shaft of the motor is rotatably connected with the top cover plate of the etching tank 12; the negative electrode liquid supply unit 1 includes a negative electrode transfer tank 5; the electrolysis unit 2 includes an electrolysis tank, and an ion membrane positive electrode tank 16 is arranged inside the electrolysis tank; the etching tank 12 inputs positive electrode liquid into the interior of the ion membrane positive electrode tank 16 through a pipeline, and the ion membrane positive electrode tank 16 returns the positive electrode liquid to the etching tank 12; the negative electrode transfer tank 5 inputs negative electrode liquid into the electrolysis tank, and the negative electrode liquid in the electrolysis tank overflows back to the negative electrode transfer tank 5; the waste gas in the electrolysis tank is absorbed and treated by the tail gas treatment unit 4.

[0033] The electrolysis unit 2 includes three electrolysis tanks arranged side by side, a negative electrode liquid overflow pipe 21 and a positive electrode liquid overflow pipe 22 are inserted between the three electrolysis tanks, the electrolysis tank is provided with a negative electrode liquid overflow port 20, and is communicated with the negative electrode liquid overflow pipe 21, and three ion membrane positive electrode tanks 16 are arranged inside each electrolysis tank.

[0034] An electrolysis positive electrode 17 is placed in each ion membrane positive electrode tank 16, and an electrolysis negative electrode 18 is placed between every two adjacent ion membrane positive electrode tanks 16.

[0035] One side of the etching tank 12 is connected with a positive electrode liquid delivery pump 11, the output end of the positive electrode liquid delivery pump 11 is connected with a positive electrode liquid input main pipe 14, the positive electrode liquid input main pipe 14 is connected with a plurality of positive electrode liquid input branch pipes 15, and the plurality of positive electrode liquid input branch pipes 15 are respectively communicated with each ion membrane positive electrode tank 16.

[0036] The negative electrode transfer tank 5 is connected with a negative electrode liquid supply main pipe 6. Specifically, the negative electrode liquid supply main pipe 6 and the negative electrode transfer tank 5 are connected with a negative electrode liquid delivery pump, the negative electrode liquid supply main pipe 6 is connected with a plurality of negative electrode liquid supply branch pipes 7, and the plurality of negative electrode liquid supply branch pipes 7 are respectively communicated with each electrolysis tank.

[0037] Each ion membrane positive electrode tank 16 is connected with a positive electrode liquid output branch pipe 19, the positive electrode liquid output branch pipe 19 is connected with a positive electrode liquid output main pipe, and the positive electrode liquid output main pipe is communicated with the etching tank 12.

[0038] The tail gas treatment unit 4 includes a tail gas treatment device 10, the tail gas treatment device 10 is connected with an exhaust main pipe 9, the exhaust main pipe 9 is connected with an exhaust branch pipe 8, and the exhaust branch pipe 8 is communicated with the electrolysis tank.

[0039] The operation mode of the device of the present invention is as follows:

[0040] ①. Anode circulation: The etching tank 12 inputs the positive electrode liquid into a plurality of ion membrane positive electrode tanks 16 through the delivery pump 11, the positive electrode liquid input main pipe 14 and the positive electrode liquid input branch pipe 15. The positive electrode liquid in the plurality of ion membrane positive electrode tanks 16 overflows back to the etching tank through the positive electrode liquid output branch pipe 19 and the positive electrode liquid output main pipe.

[0041] ②. Cathode circulation: The input end of the negative electrode liquid supply main pipe 6 is communicated with the negative electrode transfer tank 5, the output end of the negative electrode liquid supply main pipe 6 is respectively communicated with the input ends of a plurality of negative electrode liquid supply branch pipes 7, and the output end of the negative electrode liquid supply branch pipe 7 is communicated with the electrolysis tank to input the negative electrode liquid into the three electrolysis tanks. The negative electrode liquid in the electrolysis tank overflows back to the negative electrode transfer tank 5 through the negative electrode liquid overflow port 20 and the negative electrode liquid overflow pipe 21.

[0042] ③. Tail gas treatment: The input end of the exhaust branch pipe 8 is communicated with the electrolysis tank, the output end of the exhaust branch pipe 8 is communicated with the exhaust main pipe 9, and the output end of the exhaust main pipe 9 is communicated with the tail gas treatment device 10. The waste gas of the electrolysis tank is absorbed and treated by the tail gas treatment device 10.

[0043] In addition, the etching tank 12 and the ion membrane positive electrode tank 16 are filled with acidic etching solution (parameters of the acidic etching solution: copper ions 120 - 140 g / L, chlorine ions 270 - 290 g / L, acidity 1.2 - 2.5, ORP value controlled at 650 - 750 mv). The etching tank 12 inputs the positive electrode liquid into a plurality of ion membrane positive electrode tanks 16 through the positive electrode liquid delivery pump 11, the positive electrode liquid input main pipe 14 and the positive electrode liquid input branch pipe 15. The positive electrode liquid in the plurality of ion membrane positive electrode tanks 16 overflows back to the etching tank 12 through the positive electrode liquid output branch pipe 19 and the positive electrode liquid output main pipe.

[0044] The electrolysis tank and the negative electrode transfer tank 5 are filled with acidic electrolyte solution (parameters of the acidic electrolyte solution: copper ions 30 - 40 g / L, chlorine ions 180 - 230 g / L, acidity 2.5 - 4.0). The negative electrode transfer tank 5 transports the negative electrode electrolyte solution to the three electrolysis tanks through the negative electrode liquid delivery pump, the negative electrode liquid supply main pipe 6 and the negative electrode liquid supply branch pipe 7. The negative electrode electrolyte solution in the electrolysis tank overflows back to the negative electrode liquid transfer tank 5 through the negative electrode liquid overflow port 20 and the negative electrode liquid overflow pipe 21.

[0045] After the electrolysis is started, the chemical reactions occurring in the ion membrane positive electrode tank 16 are as follows:

[0046] Cu + -e - =Cu 2+ ,

[0047] 2Cl - -2e - =Cl2 ,

[0048] The chemical reaction occurring at the negative electrode:

[0049] Cu 2+ + 2e - = Cu;

[0050] The chemical reaction occurring in the etching tank 12:

[0051] Cu + Cu 2+ = 2Cu +

[0052] After electrolysis is started, cuprous ions in the positive electrode tank 16 of the ion membrane lose electrons to become cupric ions, and chloride ions lose electrons to produce chlorine gas. According to the standard electrode potential (298.15K) of Cu + / Cu 2+ being -0.159V and the standard electrode potential (298.15K) of Cl - / Cl 2 being -1.3583V, it can be known that the reaction of Cu + - e - = Cu 2+ occurs first in the positive electrode tank 16 of the ion membrane, and then the reaction of 2Cl - - 2e - = Cl 2 occurs. That is, continuously transporting cuprous ions from the etching tank 12 to the positive electrode tank 16 of the ion membrane can inhibit the generation of chlorine gas. The cupric ions generated in the positive electrode tank 16 of the ion membrane are transported to the etching tank 12 to react with copper sheets, generating cuprous ions that are transported back to the positive electrode tank 16 of the ion membrane. Thus, the purpose of reducing the generation of chlorine gas and saving the cost of treating chlorine gas is achieved.

[0053] The above shows and describes the basic principles, main features and advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention, and any reference signs in the claims should not be regarded as limiting the claims involved.

[0054] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An ion membrane experimental electrolysis device, characterized in that: It comprises a negative electrode liquid supply unit (1), an electrolysis unit (2), an etching unit (3) and an exhaust gas treatment unit (4); The etching unit (3) comprises an etching cylinder (12); the negative electrode liquid supply unit (1) comprises a negative electrode transfer cylinder (5); the electrolysis unit (2) comprises an electrolysis cylinder, and an ion membrane positive electrode tank (16) is provided inside the electrolysis cylinder; The etching cylinder (12) inputs cathode liquid into the interior of the ion membrane cathode tank (16) through a pipeline, and the ion membrane cathode tank (16) flows the cathode liquid back to the etching cylinder (12); The negative electrode transfer cylinder (5) inputs negative electrode liquid into the electrolysis cylinder, and the negative electrode liquid in the electrolysis cylinder overflows back to the negative electrode transfer cylinder (5); The waste gas from the electrolysis cylinder is absorbed and treated by a tail gas treatment unit (4).

2. An ion membrane experimental electrolysis device according to claim 1, characterized in that: The electrolysis unit (2) comprises three electrolysis cylinders arranged side by side, a cathode liquid overflow pipe (21) and a cathode liquid overflow pipe (22) are arranged between the three electrolysis cylinders, the electrolysis cylinders are provided with a cathode liquid overflow port (20) which is in communication with the cathode liquid overflow pipe (21), and each of the electrolysis cylinders is provided with four ion membrane cathode tanks (16).

3. An ion membrane experimental electrolysis device according to claim 2, characterized in that: Each of the ion membrane positive electrode slots (16) is provided with an electrolytic positive electrode (17), and an electrolytic negative electrode (18) is provided between every two adjacent ion membrane positive electrode slots (16).

4. An ion membrane experimental electrolysis device according to claim 3, characterized in that: One side of the etching cylinder (12) is connected to a cathode liquid delivery pump (11), the output end of the cathode liquid delivery pump (11) is connected to a cathode liquid input main pipe (14), the cathode liquid input main pipe (14) is connected to a plurality of cathode liquid input branch pipes (15), and the plurality of cathode liquid input branch pipes (15) are respectively connected to each ion membrane cathode tank (16).

5. An ion membrane experimental electrolysis device according to claim 4, characterized in that: The negative electrode transfer cylinder (5) is connected to a negative electrode liquid supply main pipe (6), and the negative electrode liquid supply main pipe (6) is connected to a plurality of negative electrode liquid supply branch pipes (7), and the plurality of negative electrode liquid supply branch pipes (7) are respectively connected to each electrolysis cylinder.

6. An ion membrane experimental electrolysis device according to claim 5, characterized in that: Each of the ion membrane cathode tanks (16) is connected to a cathode liquid output branch pipe (19), and the cathode liquid output branch pipe (19) is connected to a cathode liquid output main pipe, and the cathode liquid output main pipe is in communication with the etching cylinder (12).

7. An ion membrane experimental electrolysis device according to claim 6, characterized in that: The tail gas treatment unit (4) comprises a tail gas treatment device (10), the tail gas treatment device (10) is connected to an exhaust main pipe (9), the exhaust main pipe (9) is connected to an exhaust branch pipe (8), and the exhaust branch pipe (8) is connected to the electrolysis cylinder.

8. An ion membrane experimental electrolysis device according to claim 7, characterized in that: The etching cylinder (12) and the ion membrane positive electrode tank are filled with an acidic etching solution (16), and the parameters of the acidic etching solution are as follows: Copper ion 120-140g / L, chloride ion 270-290g / L, acidity 1.2-2.5, ORP value controlled at 650-750mv.

9. An ion membrane experimental electrolysis device according to claim 8, characterized in that: The electrolysis cylinder and the negative electrode transfer cylinder (5) are filled with an acidic electrolyte, and the parameters of the acidic electrolyte are as follows: Copper ion 30-40g / L, chloride ion 180-230g / L, acidity 2.5-4.

0.

10. An ion membrane experimental electrolysis device according to claim 9, characterized in that: A stirrer (13) is provided on the top surface of the etching cylinder (12).

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