Foamed titanium multi-element electrode preparation process monitoring system

Abstract

The utility model provides a foam titanium multi-element electrode preparation process monitoring system. The foam titanium multi-element electrode preparation process monitoring system comprises a tin ion concentration detection circuit, the tin ion concentration detection circuit comprises an operational amplifier U1B, an operational amplifier U1C, a resistor R1, a first subtraction circuit, a switching tube Q1, a detection electrode and a voltage detection circuit, and the in-phase input end of the operational amplifier U1B is used for being connected with a first reference voltage; the output end of the operational amplifier U1B is connected to the auxiliary electrode of the detection electrode through the resistor R1, the reference electrode of the detection electrode is connected to the in-phase input end of the operational amplifier U1C, the output end of the operational amplifier U1C is connected to the output end of the operational amplifier U1C in a feedback mode, and the output end of the operational amplifier U1C is connected to the inverted input end of the operational amplifier U1B. The tin plating effect of the titanium electrode can be improved.

Description

Technical Field

[0001] This disclosure relates to the field of electrochemical technology, and in particular to a monitoring system for the preparation process of foamed titanium multi-electrode. Background Technology

[0002] Coking wastewater contains a large amount of recalcitrant organic matter, such as phenols, biphenyls, polycyclic aromatic hydrocarbons, and nitrogen-containing heterocyclic compounds. Foamed titanium multi-electrode electrodes exhibit excellent electrocatalytic performance. During electrolysis, the electrode surface generates highly oxidizing reactive oxygen species, such as hydroxyl radicals (·OH). These reactive oxygen species can non-selectively attack organic molecules, oxidizing and decomposing them into carbon dioxide, water, or simple organic matter, thereby reducing indicators such as chemical oxygen demand (COD) and total organic carbon (TOC) in the wastewater. In recent years, they have been widely used in wastewater treatment.

[0003] The preparation process of the foamed titanium multi-electrode includes: (1) preparation of Ti-Sn electrode substrate, in which Sn is deposited on a foamed titanium substrate with microporous structure and large specific surface area by chemical plating; (2) preparation of Ti-SnO2 electrode substrate layer, in which Ti-SnO2 electrode substrate is prepared by high-temperature calcination involving F element; (3) doping with antimony tin oxide (ATO); (4) doping with rubidium (Nd).

[0004] In the preparation of Ti-Sn electrode substrate, the concentration of Sn ions (tin ions) is crucial to the tin plating effect. Therefore, an accurate Sn ion concentration detection circuit is needed to monitor the tin ion concentration in the plating solution in order to achieve accurate control of the tin ion concentration and thus improve the tin plating effect. Utility Model Content

[0005] This disclosure provides a monitoring system for the preparation process of foamed titanium multi-electrode to improve the tin plating effect of titanium electrodes.

[0006] This disclosure provides a monitoring system for the preparation process of a foamed titanium multi-electrode, including a tin ion concentration detection circuit. The tin ion concentration detection circuit includes operational amplifier U1B, operational amplifier U1C, resistor R1, a first subtraction circuit, switching transistor Q1, a detection electrode, and a voltage detection circuit.

[0007] The non-inverting input of operational amplifier U1B is connected to a first reference voltage. The output of operational amplifier U1B is connected to the auxiliary electrode of the detection electrode through resistor R1. The reference electrode of the detection electrode is connected to the non-inverting input of operational amplifier U1C. The output of operational amplifier U1C is fed back to its own output. The output of operational amplifier U1C is connected to the inverting input of operational amplifier U1B.

[0008] The working electrode of the detection electrode is connected to the first input terminal of the first subtraction circuit, the second input terminal of the first subtraction circuit is connected to a second reference voltage, the output terminal of the first subtraction circuit is connected to the control terminal of the switching transistor Q1, the first terminal of the switching transistor Q1 is connected to a first power supply, and the second terminal of the switching transistor Q1 is connected to the working electrode of the detection electrode.

[0009] The voltage detection circuit is configured to detect the voltage across the resistor R1, and the output of the voltage detection circuit is the output of the tin ion concentration detection circuit.

[0010] In one exemplary embodiment of this disclosure, the voltage detection circuit includes an operational amplifier U1D, the non-inverting input terminal of the operational amplifier U1D is connected to the first terminal of the resistor R1, the inverting input terminal of the operational amplifier U1D is connected to the second terminal of the resistor R1 through a resistor R4, and the output terminal of the operational amplifier U1D is fed back to the inverting input terminal of the operational amplifier U1D through a resistor R3.

[0011] In one exemplary embodiment of this disclosure, a voltage follower is provided between the non-inverting input terminal of the operational amplifier U1B and the first reference voltage.

[0012] In one exemplary embodiment of this disclosure, the foamed titanium multi-electrode preparation process monitoring system further includes a plating bath temperature detection circuit, which includes a thermocouple, a second subtraction circuit, an addition circuit, a thermistor R8, a resistor R9, and a third subtraction circuit.

[0013] The thermocouple is configured to detect the temperature of the plating solution. The two ends of the thermocouple are respectively connected to the two input terminals of the second subtraction circuit, and the output terminal of the second subtraction circuit is connected to the first input terminal of the addition circuit.

[0014] The thermistor R8 is configured to detect the temperature of the thermocouple reference terminal. The first terminal of the resistor R9 is connected to the first power supply. The second terminal of the resistor R9 is grounded through the thermistor R8. The second terminal of the resistor R9 is connected to the first input terminal of the third subtraction circuit. The second input terminal of the third subtraction circuit is connected to the third reference voltage. The output terminal of the third subtraction circuit is connected to the second input terminal of the addition circuit. The output terminal of the addition circuit is the output terminal of the plating solution temperature detection circuit.

[0015] In one exemplary embodiment of this disclosure, the foamed titanium multi-electrode fabrication process monitoring system further includes a first comparator and a second comparator.

[0016] The non-inverting input of the first comparator is connected to the output of the plating solution temperature detection circuit, the inverting input of the first comparator is connected to the fourth reference voltage, and the output of the first comparator is connected to the first signal input of the controller.

[0017] The inverting input of the second comparator is connected to the output of the plating solution temperature detection circuit, the non-inverting input of the second comparator is connected to the fifth reference voltage, and the output of the second comparator is connected to the second signal input of the controller.

[0018] The controller is configured to control the operation or shutdown of the heating device based on the output signals of the first comparator and the second comparator.

[0019] In one exemplary embodiment of this disclosure, the foamed titanium multi-electrode fabrication process monitoring system further includes a switch Q5 and a relay K1.

[0020] The control terminal of the switching transistor Q5 is connected to the first signal output terminal of the controller. The first terminal of the switching transistor Q5 is grounded. The second terminal of the switching transistor Q5 is connected to one end of the coil of the relay K1. The other end of the coil of the relay K1 is connected to the first power supply. The normally open contact of the relay K1 is connected in series in the power supply circuit of the heating equipment.

[0021] In one exemplary embodiment of this disclosure, the foamed titanium multi-electrode fabrication process monitoring system further includes:

[0022] The image acquisition module is configured to monitor images of the electrode surface in real time.

[0023] The working principle and beneficial effects of the foamed titanium multi-electrode preparation process monitoring system provided in this embodiment are as follows:

[0024] In this embodiment of the present disclosure, a three-electrode method is used to measure the concentration of tin ions in the plating solution. Ideally, the voltage between the reference electrode and the working electrode is constant, there is no current on the reference electrode, and the current between the auxiliary electrode and the working electrode is proportional to the concentration of tin ions in the plating solution. Therefore, the concentration of tin ions can be obtained by detecting the current between the auxiliary electrode and the working electrode.

[0025] Specifically, the arrangement of operational amplifier U1B, operational amplifier U1C, the first subtraction circuit, and the switching transistor Q1 in this embodiment ensures a constant voltage between the reference electrode and the working electrode. Its working principle is as follows: Based on the "virtual short" characteristic of the operational amplifier, the voltage at the non-inverting input terminal of operational amplifier U1B is equal to the voltage at the inverting input terminal, and both are equal to the first reference voltage. Furthermore, since the output terminal of operational amplifier U1C is connected to the inverting input terminal of operational amplifier U1B, and the output terminal of operational amplifier U1C is connected to the inverting input terminal of operational amplifier U1C, the voltage at the non-inverting input terminal of operational amplifier U1C is also equal to the first reference voltage. The first reference voltage can be provided by an external ideal voltage source. As the concentration of tin ions in the plating solution changes, the voltage at the non-inverting input terminal of operational amplifier U1C (i.e., the reference electrode) remains a constant first reference voltage.

[0026] At this point, if the working electrode potential increases, the output voltage of the first subtraction circuit decreases, the base voltage of switch Q1 decreases, the conduction degree of switch Q1 increases, the on-resistance of switch Q1 decreases, and the working electrode potential decreases. Conversely, if the working electrode potential decreases, the output voltage of the first subtraction circuit increases, the base voltage of switch Q1 increases, the conduction degree of switch Q1 decreases, the on-resistance of switch Q1 increases, and the working electrode potential increases. Through the above adjustment process, the voltage of the working electrode can be stabilized.

[0027] With stable voltages at both the reference electrode and the working electrode, the accuracy of tin ion concentration detection can be guaranteed.

[0028] Furthermore, based on the "virtual open" characteristic of the op-amp, the current at the non-inverting input terminal of op-amp U1C is zero. Therefore, the current between the auxiliary electrode and the operating current is equal to the current through resistor R1. By detecting the voltage across resistor R1, the current between the auxiliary electrode and the operating current can be obtained, and thus the tin ion concentration can be obtained.

[0029] Therefore, the arrangement of operational amplifier U1B, operational amplifier U1C, the first subtraction circuit, and the switching transistor Q1 in this embodiment ensures a constant voltage between the reference electrode and the working electrode, enabling accurate control of the tin ion concentration and thus improving the tin plating effect. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the tin ion concentration detection circuit during the preparation of the foamed titanium multi-electrode provided in this embodiment of the present disclosure;

[0032] Figure 2 This is a schematic diagram of the plating solution temperature detection circuit during the preparation of the foamed titanium multi-electrode provided in this embodiment. Detailed Implementation

[0033] To enable those skilled in the art to better understand this solution, the technical solutions in the embodiments of this solution will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this solution. Based on the embodiments of this solution, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this solution.

[0034] The term "comprising" and any other variations thereof in the specification, claims, and accompanying drawings of this invention mean "including but not limited to," and are intended to cover a non-exclusive inclusion, not limited to the examples listed herein. Furthermore, the terms "first" and "second," etc., are used to distinguish different objects, not to describe a specific order.

[0035] The implementation of this disclosure will be described in detail below with reference to the specific accompanying drawings:

[0036] Figure 1 This is a schematic diagram of the tin ion concentration detection circuit during the fabrication of the foamed titanium multi-electrode provided in this embodiment of the disclosure. (Refer to...) Figure 1 The foamed titanium multi-electrode preparation process monitoring system includes a tin ion concentration detection circuit, which comprises operational amplifier U1B, operational amplifier U1C, resistor R1, a first subtraction circuit, switching transistor Q1, detection electrode, and voltage detection circuit.

[0037] The non-inverting input of operational amplifier U1B is connected to the first reference voltage. The output of operational amplifier U1B is connected to the auxiliary electrode of the detection electrode through resistor R1. The reference electrode of the detection electrode is connected to the non-inverting input of operational amplifier U1C. The output of operational amplifier U1C is fed back to the output of operational amplifier U1C. The output of operational amplifier U1C is connected to the inverting input of operational amplifier U1B.

[0038] The working electrode of the detection electrode is connected to the first input terminal of the first subtraction circuit. The second input terminal of the first subtraction circuit is connected to the second reference voltage. The output terminal of the first subtraction circuit is connected to the control terminal of the switching transistor Q1. The first terminal of the switching transistor Q1 is connected to the first power supply, and the second terminal of the switching transistor Q1 is connected to the working electrode of the detection electrode.

[0039] The voltage detection circuit is configured to detect the voltage across resistor R1, and the output of the voltage detection circuit is the output of the tin ion concentration detection circuit.

[0040] In this embodiment, a three-electrode method is used to measure the tin ion concentration in the plating solution. Ideally, the voltage between the reference electrode and the working electrode is constant, there is no current on the reference electrode, and the current between the auxiliary electrode and the working electrode is proportional to the tin ion concentration in the plating solution. Therefore, the tin ion concentration can be obtained by detecting the current between the auxiliary electrode and the working electrode.

[0041] Considering that a redox reaction occurs on the surface of the working electrode during the tin plating process, when tin ions gain electrons on the working electrode and undergo a reduction reaction, the electron cloud density on the surface of the working electrode will change, causing its electrode potential to change. Therefore, the voltage between the working electrode and the reference electrode will change accordingly, resulting in a deviation in the tin ion concentration calculated according to the Nernst equation.

[0042] To address the aforementioned issues, the configuration of operational amplifier U1B, operational amplifier U1C, the first subtraction circuit, and switching transistor Q1 in this embodiment ensures a constant voltage between the reference electrode and the working electrode. Its working principle is as follows: Based on the "virtual short" characteristic of the operational amplifier, the voltage at the non-inverting input terminal of operational amplifier U1B is equal to the voltage at the inverting input terminal, and both are equal to the first reference voltage. Furthermore, since the output terminal of operational amplifier U1C is connected to the inverting input terminal of operational amplifier U1B, and the output terminal of operational amplifier U1C is connected to the inverting input terminal of operational amplifier U1C, the voltage at the non-inverting input terminal of operational amplifier U1C is also equal to the first reference voltage. This first reference voltage can be provided by an external voltage source. As the concentration of tin ions in the plating solution changes, the voltage at the non-inverting input terminal of operational amplifier U1C (i.e., the reference electrode) remains a constant first reference voltage.

[0043] Simultaneously, operational amplifier U5, resistors R18 and R20 constitute the first subtraction circuit. If the working electrode potential increases, the output voltage of the first subtraction circuit decreases, the base voltage of switching transistor Q1 decreases, the conduction degree of switching transistor Q1 increases, the on-resistance of switching transistor Q1 decreases, and the working electrode potential decreases. Conversely, if the working electrode potential decreases, the output voltage of the first subtraction circuit increases, the base voltage of switching transistor Q1 increases, the conduction degree of switching transistor Q1 weakens, the on-resistance of switching transistor Q1 increases, and the working electrode potential increases. Through the above adjustment process, the voltage of the working electrode can be stabilized.

[0044] With stable voltages at both the reference electrode and the working electrode, the accuracy of tin ion concentration detection can be guaranteed.

[0045] Furthermore, based on the "virtual open" characteristic of the op-amp, the current at the non-inverting input terminal of op-amp U1C is zero. Therefore, the current between the auxiliary electrode and the operating current is equal to the current through resistor R1. By detecting the voltage across resistor R1, the current between the auxiliary electrode and the operating current can be obtained, and thus the tin ion concentration can be obtained.

[0046] Therefore, the arrangement of operational amplifier U1B, operational amplifier U1C, the first subtraction circuit, and the switching transistor Q1 in this embodiment ensures a constant voltage between the reference electrode and the working electrode, enabling accurate control of the tin ion concentration and thus improving the tin plating effect.

[0047] Reference Figure 1 In one exemplary embodiment of this disclosure, the voltage detection circuit includes an operational amplifier U1D. The non-inverting input terminal of the operational amplifier U1D is connected to the first terminal of the resistor R1, the inverting input terminal of the operational amplifier U1D is connected to the second terminal of the resistor R1 through a resistor R4, and the output terminal of the operational amplifier U1D is fed back to the inverting input terminal of the operational amplifier U1D through a resistor R3.

[0048] In this embodiment, the operational amplifier U1D, resistor R4, and resistor R3 constitute a subtraction circuit, which is used to calculate and amplify the voltage difference across resistor R1. The amplification factor can be adjusted by adjusting the ratio of resistor R4 to resistor R3.

[0049] The output voltage of operational amplifier U1D is proportional to the voltage across resistor R1. The output of operational amplifier U1D can be connected to a controller. The controller can obtain the voltage across resistor R1 by reading the output voltage of operational amplifier U1D, and thus obtain the tin ion concentration. When the tin ion concentration is lower than the set value, the tin ion adding device can be activated to replenish the tin ion solution in a timely manner.

[0050] The output of the operational amplifier U1D can also be connected to a display terminal, which makes it convenient for staff to understand the tin ion concentration in real time. When the tin ion concentration is less than the set value, the tin ion solution can be replenished manually in time.

[0051] Reference Figure 1 In one exemplary embodiment of this disclosure, a voltage follower is provided between the non-inverting input terminal of operational amplifier U1B and the first reference voltage.

[0052] In this embodiment, a voltage follower is placed between the non-inverting input of the operational amplifier U1B and the first reference voltage, which can serve as an impedance match and reduce the influence of the internal resistance of the external voltage source on the first reference voltage.

[0053] Reference Figure 2 In one exemplary embodiment of this disclosure, the foamed titanium multi-electrode preparation process monitoring system further includes a plating bath temperature detection circuit, which includes a thermocouple, a second subtraction circuit, an addition circuit, a thermistor R8, a resistor R9, and a third subtraction circuit.

[0054] The thermocouple is configured to detect the temperature of the plating solution. The two ends of the thermocouple are connected to the two input terminals of a second subtraction circuit, and the output terminal of the second subtraction circuit is connected to the first input terminal of an addition circuit.

[0055] Thermistor R8 is configured to detect the temperature of the thermocouple reference terminal. The first terminal of resistor R9 is connected to the first power supply. The second terminal of resistor R9 is grounded through thermistor R8. The second terminal of resistor R9 is connected to the first input terminal of the third subtraction circuit. The second input terminal of the third subtraction circuit is connected to the third reference voltage. The output terminal of the third subtraction circuit is connected to the second input terminal of the addition circuit. The output terminal of the addition circuit is the output terminal of the plating solution temperature detection circuit.

[0056] In this embodiment, an appropriate temperature allows tin ions in the plating solution to deposit more uniformly on the surface of the titanium electrode, which is beneficial for obtaining a fine-grained and uniformly thick plating layer, reducing the possibility of defects such as pinholes and pitting, and improving the quality and performance of the plating layer. Therefore, this embodiment is equipped with a plating solution temperature detection circuit, which can monitor the plating solution temperature in real time and alert the staff to take timely measures when the temperature exceeds the normal range.

[0057] In this circuit, operational amplifier U2A, resistors R6 and R7 form the second subtraction circuit; operational amplifier U2C, resistors R15 and R13 form the addition circuit; and operational amplifier U2B, resistors R11 and R10 form the third subtraction circuit. The two ends of the thermocouple are connected to the second subtraction circuit. The output of the second subtraction circuit receives the voltage difference across the thermocouple. Therefore, the plating solution temperature can be obtained by detecting the output voltage of the second subtraction circuit.

[0058] When using thermocouples to detect the temperature of plating solution, the temperature of the thermocouple reference junction (i.e., the cold junction) should be kept constant. However, in actual testing, the temperature of the thermocouple reference junction will change with the surrounding environment, thus affecting the detection accuracy. To address this issue, this embodiment incorporates a thermistor R8 at the reference terminal of the thermocouple. When the ambient temperature rises, the temperature of the thermocouple reference terminal increases, leading to a decrease in the output voltage of the second subtraction circuit. At this time, the resistance of thermistor R8 increases, resulting in a higher voltage drop across it. Consequently, the output voltage of the third subtraction circuit becomes positive and is connected to the second input terminal of the adder circuit. This voltage is then superimposed on the output of the second subtraction circuit, compensating for the decrease in output voltage caused by the increased temperature of the thermocouple reference terminal. Conversely, when the ambient temperature decreases, the temperature of the thermocouple reference terminal decreases, leading to an increase in the output voltage of the second subtraction circuit. Again, the resistance of thermistor R8 decreases, resulting in a lower voltage drop across it. Consequently, the output voltage of the third subtraction circuit becomes negative and is connected to the second input terminal of the adder circuit. This voltage is then superimposed on the output of the second subtraction circuit, again compensating for the decrease in output voltage caused by the increased temperature of the thermocouple reference terminal. The third reference voltage is the voltage drop across the thermistor R8 at a set temperature, which is also the set temperature of the thermocouple reference terminal.

[0059] As can be seen from the above, the addition circuit, thermistor R8, resistor R9 and third subtraction circuit in this embodiment can compensate for the temperature detection error caused by the temperature change of the thermocouple reference terminal, which is beneficial to improving the accuracy of plating solution temperature detection.

[0060] Reference Figure 2 In one exemplary embodiment of this disclosure, the foamed titanium multi-electrode fabrication process monitoring system further includes a first comparator and a second comparator.

[0061] The non-inverting input of the first comparator is connected to the output of the plating solution temperature detection circuit, the inverting input of the first comparator is connected to the fourth reference voltage, and the output of the first comparator is connected to the first signal input of the controller.

[0062] The inverting input of the second comparator is connected to the output of the plating solution temperature detection circuit, the non-inverting input of the second comparator is connected to the fifth reference voltage, and the output of the second comparator is connected to the second signal input of the controller.

[0063] The controller is configured to control the operation or shutdown of the heating device based on the output signals of the first comparator and the second comparator.

[0064] In this embodiment, the fourth reference voltage is the upper limit of the plating solution temperature, and the fifth reference voltage is the lower limit of the plating solution temperature. When the plating solution temperature is greater than the upper limit, the first comparator U3A outputs a high level and the second comparator U3B outputs a low level. When the plating solution temperature is between the upper and lower limits, the first comparator U3A outputs a low level and the second comparator U3B outputs a low level. When the plating solution temperature is less than the lower limit, the first comparator U3A outputs a low level and the second comparator U3B outputs a high level.

[0065] The output signals of the first comparator U3A and the second comparator U3B can be connected to the controller. The controller can then determine whether the temperature of the plating solution is within the normal temperature range (i.e., between the upper and lower limits). When the upper limit is exceeded, the controller outputs a control signal (e.g., a low-level signal) to the control terminal of the heating equipment to shut down the heating equipment in time. When the temperature is below the lower limit, the controller outputs a control signal (e.g., a high-level signal) to the control terminal of the heating equipment to turn on the heating equipment in time.

[0066] The controller can be a commonly used microcontroller, DSP, ARM, or other control chip.

[0067] As can be seen from the above, the setting of the first comparator U3A and the second comparator U3B in this embodiment is beneficial to keeping the temperature of the plating solution within the normal temperature range, while avoiding frequent turning the heating equipment on or off.

[0068] Reference Figure 2 In one exemplary embodiment of this disclosure, the foamed titanium multi-electrode fabrication process monitoring system further includes a switch Q5 and a relay K1.

[0069] The control terminal of the switching transistor Q5 is connected to the first signal output terminal of the controller. The first terminal of the switching transistor Q5 is grounded. The second terminal of the switching transistor Q5 is connected to one end of the coil of the relay K1. The other end of the coil of the relay K1 is connected to the first power supply. The normally open contact of the relay K1 is connected in series in the power supply circuit of the heating equipment.

[0070] In this embodiment, the switching transistor Q5 can amplify the control signal output by the controller. When the first signal output terminal of the controller is high, the switching transistor Q5 is turned on, the coil of the relay K1 is energized, the normally open contact of the relay K1 is closed, and the heating equipment is powered on and works. When the first signal output terminal of the controller is low, the switching transistor Q5 is turned off, the coil of the relay K1 is de-energized, the normally open contact of the relay K1 is closed, and the heating equipment is powered off and stops working.

[0071] In one exemplary embodiment of this disclosure, the foamed titanium multi-electrode fabrication process monitoring system further includes:

[0072] The image acquisition module is configured to monitor images of the electrode surface in real time.

[0073] In this embodiment, the image acquisition module can acquire images of the electrode surface in real time. By analyzing the images of the electrode surface, changes in the surface morphology, crystal structure, etc. of the electrode can be understood in real time.

[0074] The above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit it. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure.

Claims

1. A monitoring system for the preparation process of foamed titanium multi-electrode, characterized in that, The circuit includes a tin ion concentration detection circuit, which comprises operational amplifier U1B, operational amplifier U1C, resistor R1, a first subtraction circuit, switching transistor Q1, detection electrodes, and a voltage detection circuit. The non-inverting input of operational amplifier U1B is connected to a first reference voltage. The output of operational amplifier U1B is connected to the auxiliary electrode of the detection electrode through resistor R1. The reference electrode of the detection electrode is connected to the non-inverting input of operational amplifier U1C. The output of operational amplifier U1C is fed back to its own output. The output of operational amplifier U1C is connected to the inverting input of operational amplifier U1B. The working electrode of the detection electrode is connected to the first input terminal of the first subtraction circuit, the second input terminal of the first subtraction circuit is connected to a second reference voltage, the output terminal of the first subtraction circuit is connected to the control terminal of the switching transistor Q1, the first terminal of the switching transistor Q1 is connected to a first power supply, and the second terminal of the switching transistor Q1 is connected to the working electrode of the detection electrode. The voltage detection circuit is configured to detect the voltage across the resistor R1, and the output of the voltage detection circuit is the output of the tin ion concentration detection circuit.

2. The monitoring system for the preparation process of foamed titanium multi-electrode as described in claim 1, characterized in that, The voltage detection circuit includes an operational amplifier U1D. The non-inverting input of the operational amplifier U1D is connected to the first terminal of the resistor R1. The inverting input of the operational amplifier U1D is connected to the second terminal of the resistor R1 through a resistor R4. The output of the operational amplifier U1D is fed back to the inverting input of the operational amplifier U1D through a resistor R3.

3. The monitoring system for the preparation process of foamed titanium multi-electrode as described in claim 1, characterized in that, A voltage follower is provided between the non-inverting input terminal of the operational amplifier U1B and the first reference voltage.

4. The monitoring system for the preparation process of foamed titanium multi-electrode as described in claim 1, characterized in that, It also includes a plating solution temperature detection circuit, which comprises a thermocouple, a second subtraction circuit, an addition circuit, a thermistor R8, a resistor R9, and a third subtraction circuit. The thermocouple is configured to detect the temperature of the plating solution. The two ends of the thermocouple are respectively connected to the two input terminals of the second subtraction circuit, and the output terminal of the second subtraction circuit is connected to the first input terminal of the addition circuit. The thermistor R8 is configured to detect the temperature of the thermocouple reference terminal. The first terminal of the resistor R9 is connected to the first power supply. The second terminal of the resistor R9 is grounded through the thermistor R8. The second terminal of the resistor R9 is connected to the first input terminal of the third subtraction circuit. The second input terminal of the third subtraction circuit is connected to the third reference voltage. The output terminal of the third subtraction circuit is connected to the second input terminal of the addition circuit. The output terminal of the addition circuit is the output terminal of the plating solution temperature detection circuit.

5. The monitoring system for the preparation process of foamed titanium multi-electrode as described in claim 4, characterized in that, It also includes a first comparator and a second comparator. The non-inverting input of the first comparator is connected to the output of the plating solution temperature detection circuit, the inverting input of the first comparator is connected to the fourth reference voltage, and the output of the first comparator is connected to the first signal input of the controller. The inverting input of the second comparator is connected to the output of the plating solution temperature detection circuit, the non-inverting input of the second comparator is connected to the fifth reference voltage, and the output of the second comparator is connected to the second signal input of the controller. The controller is configured to control the operation or shutdown of the heating device based on the output signals of the first comparator and the second comparator.

6. The monitoring system for the preparation process of foamed titanium multi-electrode as described in claim 5, characterized in that, It also includes switching transistor Q5 and relay K1. The control terminal of the switching transistor Q5 is connected to the first signal output terminal of the controller. The first terminal of the switching transistor Q5 is grounded. The second terminal of the switching transistor Q5 is connected to one end of the coil of the relay K1. The other end of the coil of the relay K1 is connected to the first power supply. The normally open contact of the relay K1 is connected in series in the power supply circuit of the heating equipment.

7. The monitoring system for the preparation process of foamed titanium multi-electrode as described in claim 1, characterized in that, Also includes: The image acquisition module is configured to monitor images of the electrode surface in real time.

Images