Dual-wavelength spectrophotometric nephelometry colorimetric probe and application thereof

Abstract

The application provides a double-wavelength spectrophotometric turbidimetry colorimetric probe and application thereof, the colorimetric probe comprises a light source, a sample cell and a photoelectric receiving assembly arranged in sequence; the photoelectric receiving assembly comprises a first photoelectric receiving assembly and a second photoelectric receiving assembly; light in the light source is divided into two paths after passing through the sample cell, and light of different wavelengths enters the first photoelectric receiving assembly and the second photoelectric receiving assembly respectively, and a first electric signal is output by the first photoelectric receiving assembly, and a second electric signal is output by the second photoelectric receiving assembly. Compared with the prior art, the colorimetric probe provided by the application, in combination with the use of the double-wavelength spectrophotometric turbidimetry, can accurately calculate the concentration of chloride ions in the acid copper tank solution through the absorbance of different wavelengths, not only the detection speed is fast, but also the accuracy and precision of measurement can be ensured when the content of chloride ions is 0.1 mg / L, and the problem of low data accuracy of the detection method for the detection of trace chloride ions in the acid copper tank solution is effectively solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of turbidimetry detection, in particular to a colorimetric probe for dual-wavelength spectrophotometric turbidimetry and application thereof. BACKGROUND

[0002] Acid copper plating is widely used in electrolytic copper foil, decorative plating, conductivity, weldability and surface plating, etc. It can effectively improve the leveling, ductility and brightness of the plating layer, and reduce the cost of electroplating. It is used in printed circuit board (PCB), laser cutting, thin film capacitor, solar panel, etc. The main components and control range of acid copper are as follows: (1) Cu 2+ : 80-140 g / L, (2) Cl - <30 mg / L.

[0003] In the process of acid copper plating, chloride ion in acid copper is an important component. In order to obtain good quality of copper plating layer, in addition to the conventional process parameters such as temperature, voltage, current, etc., the concentration of chloride ion must be controlled within a certain range. In the production process of acid copper plating, the acid copper bath contains a large amount of SO4 2- , Cu 2+ and a small amount of Cl - ions. Since Cl - can accelerate the discharge reaction of Cu 2+ ions, a certain concentration will also affect the activity of Cu deposition layer. Too high or too low Cl - content will result in lower Cu deposition activity, thereby reducing the leveling, brightness and mechanical properties of the plating layer. Therefore, monitoring and controlling the Cl - content is of great significance.

[0004] Due to the low Cl - content in the acid copper bath, the presence of a large amount of Cu 2+ ions will interfere with the end point observation of chloride ions when using conventional analysis methods, affecting the test accuracy. The current analysis methods mainly include potentiometric titration, ion selective electrode method, visual turbidimetry and single-wavelength spectrophotometric turbidimetry, etc. The potentiometric titration method is mainly for high concentration Cl - ; although the ion selective electrode method can be used for determination of small amount of Cl - content, due to the limitation of chloride ion electrode (lower limit of range is 1.8 mg / L), it cannot meet the determination of chloride ion content with lower content; visual turbidimetry is a visual color observation of silver chloride precipitation, which is subjective and can only be limited to laboratory detection, and the accuracy and precision cannot be guaranteed; the measurement speed of single-wavelength spectrophotometric turbidimetry is slow, and standard solution needs to be prepared for each measurement.

[0005] Therefore, it is necessary to provide a technical solution to solve the above problems. SUMMARY

[0006] One of the purposes of the present application is to provide a double-wavelength spectrophotometric turbidimetry colorimetric probe to solve the problem of low data accuracy in the detection method for detecting trace amounts of chloride ions in the acid copper tank solution.

[0007] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0008] A double-wavelength spectrophotometric turbidimetry colorimetric probe, comprising a light source, a sample cell and a photoelectric receiving assembly arranged in sequence; the photoelectric receiving assembly comprises a first photoelectric receiving assembly and a second photoelectric receiving assembly; the light in the light source passes through the sample cell and is divided into two paths of different wavelengths, and enters the first photoelectric receiving assembly and the second photoelectric receiving assembly respectively, and outputs a first electric signal by the first photoelectric receiving assembly, and outputs a second electric signal by the second photoelectric receiving assembly.

[0009] Preferably, the first photoelectric receiving assembly comprises a first monochromatic filter and a first photoelectric signal converter arranged in sequence, the first monochromatic filter is used to obtain a monochromatic light measurement wavelength, and the first photoelectric signal converter is used to receive the light signal of the first monochromatic filter and convert it into a first electric signal output.

[0010] The second photoelectric receiving assembly comprises a second monochromatic filter and a second photoelectric signal converter arranged in sequence, the second monochromatic filter is used to obtain a monochromatic light reference wavelength, and the second photoelectric signal converter is used to receive the light signal of the second monochromatic filter and convert it into a second electric signal output.

[0011] Preferably, the monochromatic light measurement wavelength ranges from 400nm to 450nm, and the monochromatic light reference wavelength ranges from 560nm to 600nm.

[0012] Preferably, the colorimetric probe further comprises a signal external terminal for outputting the first electric signal and the second electric signal to an external circuit.

[0013] The second purpose of the present application is to provide a detection system for detecting the chloride ion content in the acid copper tank solution, comprising a detection unit, the detection unit comprising:

[0014] A reaction part for mixing the acid copper tank solution with an auxiliary reagent to obtain a to-be-detected acid copper tank solution.

[0015] A colorimetric probe, which is the double-wavelength spectrophotometric turbidimetry colorimetric probe described above, is used to detect the concentration of chloride ions in the to-be-detected acid copper tank solution.

[0016] Preferably, the detection unit further comprises a first sampling part and a second sampling part; the first sampling part is connected with the reaction part, and is used for extracting the acid copper tank solution into the reaction part; one end of the second sampling part is connected with the reaction part, and the other end is connected with a sample pool in the colorimetric probe, and is used for extracting the mixed acid copper tank solution in the reaction part into the sample pool of the colorimetric probe.

[0017] Preferably, the first sampling part comprises a multi-channel valve group, which is used for switching the extraction of the acid copper tank solution and the auxiliary reagent.

[0018] Preferably, the reaction part further comprises a stirring part, which is used for mixing the acid copper tank solution and the auxiliary reagent.

[0019] Preferably, the detection unit further comprises a first waste discharge assembly and a second waste discharge assembly; the first waste discharge assembly is connected with the reaction part, and is used for discharging the waste liquid in the reaction part; and the second waste discharge assembly is connected with the colorimetric probe, and is used for discharging the waste liquid in the colorimetric probe.

[0020] Preferably, the detection system further comprises a control unit and a dosing supplement unit; the control unit is electrically connected with the colorimetric probe and the dosing supplement unit respectively, and is used for feeding back the result of the colorimetric probe to the dosing supplement unit.

[0021] The third object of the present application is to provide a detection method for the content of chloride ions in an acid copper tank solution, comprising the following steps:

[0022] After the acid copper tank solution to be detected is diluted, the solution is added into the sample pool, and then HNO3 solution, emulsifier solution and AgNO3 solution are sequentially added; after standing for 15-30 min, the detection is performed through the colorimetric probe, so as to obtain a first electric signal and a second electric signal output by two different wavelengths; the absorbance difference ΔA of the first electric signal and the second electric signal is calculated, and then compared with a chloride ion standard curve, so as to obtain the concentration of the chloride ions in the diluted acid copper tank solution to be detected; and the concentration of the chloride ions in the acid copper tank solution to be detected is calculated according to the dilution multiple; the colorimetric probe is the double-wavelength spectrophotometric turbidimetry colorimetric probe as described above.

[0023] Preferably, the preparation method of the chloride ion standard curve is as follows: first, a CuSO4·5H2O solution is used as a base solution, and chloride ion standard solutions with different concentrations are prepared for standby; then, the absorbance of light of the chloride ion standard solutions with different concentrations is measured at the set measurement wavelength and reference wavelength by using the silver chloride turbidimetry method, the absorbance difference ΔA of the measurement wavelength and the reference wavelength is calculated, and the standard curve of the absorbance difference ΔA and the chloride ion concentration is made.

[0024] After the concentration of the chloride ion in the acid copper tank solution to be measured is obtained, the concentration is compared with the set concentration limit value, and the comparison result is fed back to the dosing and supplementing unit through the signal external connection end of the colorimetric probe, so that the online automatic detection of the chloride ion content in the acid copper tank solution is realized.

[0025] Preferably, the concentration of the HNO3 solution is 1.4g / cm 3 ; the emulsifier solution is 30% Triton X-100 and 30% ethylene glycol solution; and the concentration of the CuSO4*5H2O solution is 0.10mol / L.

[0026] The colorimetric probe provided by the application is used in the double-wavelength spectrophotometric turbidimetry, light is divided into light of different energy wavelengths after passing through the same sample pool and enters the first photoelectric receiving assembly and the second photoelectric receiving assembly, that is, the light in the colorimetric probe of the application passes through the same sample alternately, different wavelength light is obtained, the difference between the absorbances of the two is used for calculation to obtain the trace chloride ion in the acid copper tank solution, the detection speed is fast, the accuracy and precision of the measurement can be ensured when the chloride ion content is 0.1mg / L, and the problem of low data accuracy in the detection method for the trace chloride ion content in the acid copper tank solution is effectively solved. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is a front view of the colorimetric probe.

[0028] Figure 2 It is a top view of the colorimetric probe.

[0029] Figure 3 It is a structural schematic view of the detection unit.

[0030] Figure 4 It is a front view of the detection system.

[0031] Figure 5 It is a sectional view of the A direction of the detection system. Figure 4

[0032] ​In the figure: 1-detection unit; 11-reaction part; 111-stirring part; 12-colorimetric probe; 121-light source; 122-sample cell; 1221-sample flow inlet; 1222-sample flow outlet; 123-first photoelectric receiving assembly; 1231-first monochromatic filter; 1232-first photoelectric signal converter; 124-second photoelectric receiving assembly; 1241-second monochromatic filter; 1242-second photoelectric signal converter; 125-signal external terminal; 13-first sampling part; 131-multichannel valve group; 132-first sampling pump; 14-second sampling part; 15-first waste discharge assembly; 151-first waste discharge valve; 152-first waste discharge pump; 16-second waste discharge assembly; 161-second waste discharge valve; 162-second waste discharge pump; 17-switching valve; 2-control unit; 3-dosing replenishment unit. DETAILED DESCRIPTION

[0033] In order to make the technical solutions and advantages of the present application clearer, the present application and its beneficial effects will be further described in detail below in combination with specific embodiments and the drawings of the specification, but the embodiments of the present application are not limited thereto.

[0034] The acid copper bath solution preferably refers to a sulfate copper plating bath solution used in the electrolytic copper foil industry.

[0035] At present, the Cl - content of the acid copper bath solution is mainly determined and controlled by a chemist manually sampling on the production line, analyzed according to the following test method, and then the worker adds chloride salt according to the test results, or arranges whether to stop production according to whether the Cl - concentration exceeds the upper limit of control, and disposes the chloride ion.

[0036] The specific test method is as follows:

[0037] (1) Reagents and instruments:

[0038] Cl - standard solution: 20 mg / L;

[0039] AgNO3 solution: 0.005 mol / L;

[0040] Basic base solution: CuSO4·5H2O: 200 g / L, H2SO4: 62.5 g / L, 510 opening agent: 7 mL, 510A filling agent: 0.6 mL, 510B brightener: 0.5 mL / L;

[0041] Emulsifier solution: OP solution, obtained by mixing OP with water at V (OP) :V (水) =1:3;

[0042] HNO3 solution: nitric acid and water at V(HNO3) :V (水) =1:1 mixture.

[0043] Test solution: 5.00 mL of copper sulfate solution was taken in a 50 mL volumetric flask, and water was added to constant volume, mixed well for use;

[0044] Instrument: 721 spectrophotometer; 2 cm cuvette.

[0045] (2) Analysis and calculation steps:

[0046] A, draw the chloride standard curve: in six cuvettes, each add 0.5 mL of basic base, then add chloride standard solution 0, 0.50, 1.00, 2.00, 3.00, 4.00 mL, add water to 5 mL. With this series of solutions, the standard curve is drawn, and the regression equation is obtained;

[0047] B, analysis of test solution: take two cuvettes (x and y), each add 5.00 mL of test solution, then add 1.0 mL of HNO3 solution, 1.0 mL of OP emulsifier solution, and x tube adds 1.0 mL of AgNO3 solution, while y tube does not add; With y tube as reference, the absorbance of x tube was tested by 721 spectrophotometer, and the regression equation of standard curve was compared to calculate the concentration of chloride ion;

[0048] The calculation formula is: C (Cl-) (mg / L) = m (待测液) (μg) × 2

[0049] But the above test method mainly uses 721 spectrophotometer to divide a beam of light into two equal energy light paths, one through the reference and the other through the test solution. The absorbance measured is calculated by comparing the standard curve to obtain the concentration of chloride ion, but there are still many problems:

[0050] 1) The analyst takes samples on the production line, with strong acid gas, which damages human health and increases labor intensity;

[0051] 2) This method is only suitable for analysis in the laboratory, but the laboratory analysis has great limitations and many human factors, with large analysis error, which cannot guarantee the accuracy and precision of the test, especially at low concentration (less than 0.1 mg / L) The accuracy is greatly reduced.

[0052] Based on this, like Figures 1-2As shown, the first aspect of the present application aims to provide a colorimetric probe for dual-wavelength spectrophotometric turbidimetry, comprising a light source 121, a sample cell 122 and a photoelectric receiving assembly arranged in sequence; the photoelectric receiving assembly comprises a first photoelectric receiving assembly 123 and a second photoelectric receiving assembly 124; the light in the light source 121 passes through the sample cell 122 and is divided into two different wavelengths of light, which respectively enters the first photoelectric receiving assembly 123 and the second photoelectric receiving assembly 124, and the first photoelectric receiving assembly 123 outputs a first electric signal, and the second photoelectric receiving assembly 124 outputs a second electric signal.

[0053] By using the colorimetric probe 12 in combination with the use of dual-wavelength spectrophotometric turbidimetry, the concentration of chloride ions in the acid copper tank can be accurately calculated by the absorbance difference of different wavelengths, which not only has a fast detection speed, but also can ensure the accuracy and precision of the measurement under the content of 0.1 mg / L of chloride ions, effectively solving the problem of low data accuracy of the current detection method for the detection of trace chloride ions in the acid copper tank.

[0054] Unlike the test method combined with the 721 type spectrophotometer, the colorimetric probe 12 provided by the present application is suitable for dual-wavelength spectrophotometric turbidimetry, that is, a beam of light is divided into two different energy wavelengths, which alternately passes through the same sample by switching, and the absorbance difference is used for calculation, which has higher accuracy, lower minimum detectable chloride ion content, and is more convenient. In addition, the dual-wavelength spectrophotometric turbidimetry of the present application is more conducive to the analysis of multi-component mixtures, turbid samples, and situations where there is background interference or coexisting component absorption interference, and can improve the sensitivity and selectivity of the method.

[0055] In some embodiments, the first photoelectric receiving assembly 123 comprises a first monochromatic filter 1231 and a first photoelectric signal converter 1232 arranged in sequence, the first monochromatic filter 1231 is used to obtain a monochromatic light measurement wavelength (λ p ); the first photoelectric signal converter 1232 is used to receive the light signal I1 of the measurement wavelength λ p of the first monochromatic filter 1231 and convert it into a first electric signal V1 output.

[0056] In some embodiments, the second photoelectric receiving assembly 124 comprises a second monochromatic filter 1241 and a second photoelectric signal converter 1242 arranged in sequence, the second monochromatic filter 1241 is used to obtain a monochromatic light reference wavelength (λ s ), and the second photoelectric signal converter 1242 is used to receive the light signal I2 of the reference wavelength λ s of the second monochromatic filter 1241 and convert it into a second electric signal V2 output.

[0057] By using a monochromatic filter, monochromatic light of different wavelengths can be obtained, and when the measurement wavelength λp Compared with the reference wavelength λ s When chosen appropriately, light scattering and background absorption can be ignored, further improving measurement accuracy. Preferably, additional filters can be added to eliminate interference and improve wavelength selectivity.

[0058] In some embodiments, the monochromatic light measurement wavelength range is 400–450 nm; the monochromatic light reference wavelength range is 560–600 nm. The specific range can be selected based on the effects of light scattering and the difference in wavelength absorption.

[0059] In some embodiments, the light source 121 may be any light source 121 capable of providing white light, such as an LED or a tungsten lamp.

[0060] In some embodiments, the sample cell 122 is a container for holding samples, with a width of 10-20 mm, and is made of quartz or glass.

[0061] In some embodiments, the sample pool 122 includes a sample flow inlet 1221 for sample introduction and a sample flow outlet 1222 for sample discharge.

[0062] In some embodiments, the colorimetric probe 12 further includes a signal external terminal 125 for outputting a first electrical signal and a second electrical signal to an external circuit. By adding the signal external terminal 125, the colorimetric probe 12 of the present invention can be better integrated into an online detection system for analyzing the chloride ion content in an acid copper bath, thereby achieving automatic analysis and automatic dosing control of the chloride ion content.

[0063] A second aspect of this invention aims to provide a detection system for detecting the chloride ion content in an acid copper bath, such as... Figures 4-5 As shown, it includes a detection unit 1, a control unit 2, and a dosing replenishment unit 3.

[0064] Among them, such as Figure 3 As shown, the detection unit 1 includes a reaction section 11 and the aforementioned colorimetric probe 12. The reaction section 11 is used to mix the copper acid bath solution with auxiliary reagents to obtain the copper acid bath solution to be tested. The colorimetric probe 12 is used to detect the concentration of chloride ions in the copper acid bath solution to be tested. The control unit 2 is electrically connected to the colorimetric probe 12 and the dosing replenishment unit 3, respectively, and is used to feed back the result of the colorimetric probe 12 to the dosing replenishment unit 3.

[0065] Specifically, the control unit 2 can be a PLC control unit, has a man-machine operation interface, can upload analysis, dosing and alarm information according to Modbus protocol through Ethernet TCP / IP network communication, and the analysis, dosing and alarm information can be stored and exported, and the alarm information can be set with multiple foolproof alarm functions to better monitor the content of chloride ions and the addition of chloride salt online. The dosing supplement unit 3 can automatically adjust the addition amount of chloride salt according to the analysis results of multiple times in succession, so that the process parameters of electrolytic copper foil are more stable.

[0066] In some embodiments, the shell of the detection system is a cabinet, which can be a sheet metal baking cabinet, and the overall size is 1650mm*600mm*380mm (high*wide*deep). It can also be other sizes, which are not limited here.

[0067] The auxiliary reagent includes HNO3 solution, emulsifier solution, AgNO3 solution, etc. AgNO3 can react with chloride ions in the test solution to form silver chloride suspension under the action of emulsifier, and the system reaches stability after a certain time.

[0068] In some embodiments, the detection unit 1 further comprises a first sampling part 13 and a second sampling part 14; the first sampling part 13 is connected with the reaction part 11, for extracting the acid copper tank solution into the reaction part 11; one end of the second sampling part 14 is connected with the reaction part 11, and the other end is connected with the sample cell 122 in the colorimetric probe 12, for extracting the mixed test acid copper tank solution in the reaction part 11 into the sample cell 122 of the colorimetric probe 12.

[0069] In some embodiments, the first sampling part 13 comprises a multi-channel valve group 131 for switching the extraction of acid copper tank solution and auxiliary reagent. Specifically, 8 valve ports can be provided for switching sampling of acid copper tank solution, base solution, auxiliary reagent, pure water and standard sample. Preferably, the valve port for controlling the acid copper tank solution is arranged at the lowermost end, and the standard sample is arranged at the uppermost end.

[0070] In some embodiments, the first sampling part 13 further comprises a first sampling pump 132 connected with the multi-channel valve group 131, for extracting the raw materials in the multi-channel valve group 131 into the reaction part 11.

[0071] In some embodiments, the second sampling part 14 can be a second sampling pump, which is used to extract the test solution in the reaction part 11 into the sample cell 122 in the colorimetric probe 12 for analysis after the test solution is stably placed for 15-30 minutes.

[0072] In some embodiments, the reaction unit 11 further comprises a stirring device 111 for mixing the copper sulfate solution and the auxiliary reagent. The stirring device 111 comprises a stirring motor and a stirring magnet, which cooperate to mix the copper sulfate solution and the auxiliary reagent sufficiently.

[0073] In some embodiments, the detection unit 1 further comprises a first waste discharge assembly 15 and a second waste discharge assembly 16; the first waste discharge assembly 15 is connected to the reaction unit 11 for discharging the waste liquid in the reaction unit 11; the second waste discharge assembly 16 is connected to the colorimetric probe 12 for discharging the waste liquid in the colorimetric probe 12.

[0074] Specifically, the first waste discharge assembly 15 can be composed of a first waste discharge valve 151 and a first waste discharge pump 152 connected to the first waste discharge valve 151. After the reaction and analysis of the sample in the reaction unit 11 are completed, the first waste discharge valve 151 and the first waste discharge pump 152 are opened to discharge the waste liquid in the reaction unit 11. The first waste discharge valve 151 can be an electromagnetic valve.

[0075] The second waste discharge assembly 16 can be composed of a second waste discharge valve 161 and a second waste discharge pump 162 connected to the second waste discharge valve 161. After the analysis of the sample in the colorimetric probe 12 is completed, the second waste discharge valve 161 and the second waste discharge pump 162 are opened to discharge the waste liquid in the sample cell 122 of the colorimetric probe 12. The second waste discharge valve 161 can also be an electromagnetic valve.

[0076] In some embodiments, the detection unit 1 further comprises a switching valve 17 connected to the first sampling pump 132 for controlling the switching of the sampling pipeline rinsing and the sampling waste discharge. Specifically, it can be a two-position three-way valve for sampling and waste discharge switching.

[0077] Specifically, the analysis process of the detection system of the present application is as follows:

[0078] 1) The first sampling pump 132 draws each stock solution, rinses the pipeline of the multi-channel valve group 131, and discharges the waste liquid by controlling the switching valve 17;

[0079] 2) After rinsing, the outlet of the multi-channel valve group 131 is switched to the reaction unit 11, and the multi-channel valve group 131 is switched to draw pure water to the reaction unit 11 to dilute the copper sulfate solution;

[0080] 3) The other valves of the multi-channel valve group 131 are switched again to draw the required auxiliary reagent to the reaction unit 11 for reaction (if necessary, a chloride standard sample can be drawn to calibrate the instrument);

[0081] 4) The stirring assembly in the reaction unit 11 starts to work to mix the mixed liquid in it sufficiently, and the volume is fixed to obtain the sample to be measured;

[0082] 5) The second sampling unit 14 extracts the sample solution to be measured into the sample cell 122 of the colorimetric probe 12, and the concentration is analyzed in combination with the basic database;

[0083] 6) The electrical signal of the colorimetric probe 12 can be converted into the chloride ion concentration value and transmitted to the control unit 2, which records and controls the chloride salt addition content.

[0084] The third aspect of the present application aims to provide a method for detecting the chloride ion content in an acid copper tank solution, comprising the following steps:

[0085] After diluting the acid copper tank solution to be measured, the sample cell 122 is added, and then HNO3 solution, emulsifier solution and AgNO3 solution are sequentially added, and then the solution is allowed to stand for 15-30 min, and then the colorimetric probe 12 is used for measurement to obtain first and second electrical signals of two different wavelengths, the absorbance difference ΔA of the first and second electrical signals is calculated, and then compared with the chloride ion standard curve to obtain the concentration of the chloride ion in the diluted acid copper tank solution to be measured, and the concentration of the chloride ion in the acid copper tank solution to be measured is calculated according to the dilution factor, and the colorimetric probe 12 is the colorimetric probe 12 for the double-wavelength spectrophotometric turbidimetry described above.

[0086] In some embodiments, the preparation method of the chloride ion standard curve is as follows: first, a CuSO4·5H2O solution is used as a base solution to prepare chloride ion standard solutions with different concentrations for standby; then, the absorbance of light of the chloride ion standard solutions with different concentrations is measured at the set measurement wavelength and reference wavelength by using the silver chloride turbidimetry method, the absorbance difference ΔA of the measurement wavelength and the reference wavelength is calculated, and the standard curve of the absorbance difference ΔA and the chloride ion concentration is prepared.

[0087] After obtaining the concentration of the chloride ion in the acid copper tank solution to be measured, the concentration is compared with the set concentration limit value, and the comparison result is fed back to the dosing and replenishing unit 3 through the signal external connection end 125 of the colorimetric probe 12, so as to realize the online automatic detection of the chloride ion content in the acid copper tank solution.

[0088] In some embodiments, the concentration of the HNO3 solution is 1.4 g / cm 3 , the emulsifier solution is 30% Triton X-100 or 30% ethylene glycol solution, and the concentration of the CuSO4·5H2O solution is 0.10 mol / L.

[0089] Specifically, the working principle of the double-wavelength spectrophotometric turbidimetry method of the present application is as follows: after the incident light of the same light source 121 passes through the acid copper tank solution to be measured, the light passes through the first monochromatic filter 1231 and the second monochromatic filter 1241, respectively, and two monochromatic light measurement wavelengths λ p and monochromatic light reference wavelengths λ s can be obtained.

[0090]

[0091]

[0092] From formula (2) to formula (1)

[0093] Wherein, I 01 , I1 is the incident light intensity and the exit light intensity after the acid copper tank solution to be measured, I 02 , I2 is the incident light intensity and the exit light intensity of the reference sample, and the ion concentration after the acid copper tank solution to be measured and the linear relationship of the two wavelengths of ΔA or lg(I1 / I2) can be obtained from formula (3).

[0094] Based on this, the analysis method for analyzing the content of chloride ions in the acid copper tank solution can be obtained by the dual-wavelength spectrophotometric turbidimetry combined with an online detection system.

[0095] (1) Reagent and instrument:

[0096] Cl - Ion standard solution: 0.2, 0.4, 0.8, 1.2, 1.6 mg / L;

[0097] AgNO3 solution: 0.10 mol / L;

[0098] Basic base solution: CuSO4·5H2O: 0.10 mol / L;

[0099] Emulsifier solution: 30% Triton X-100 or 30% ethylene glycol solution;

[0100] HNO3 solution: HNO3 specific gravity is 1.4 g / cm 3 , and is prepared according to V (HNO3) : V (水) =1:1;

[0101] To be measured liquid: dilute acid copper tank solution, the dilution multiple can be 2-10 times, preferably 5 times or 10 times;

[0102] Instrument: dual-wavelength spectrophotometer; 10-20 mm cuvette.

[0103] (2) Analysis and calculation steps:

[0104] A, determine the measurement wavelength and the reference wavelength: add silver nitrate in the chlorine-containing solution, under the action of a certain acidity (HNO3 medium) and stabilizer, Cl -The AgCl suspension is generated by reacting with AgNO3, and the determination is performed by using a double-wavelength spectrophotometer within 15-30 min, and the absorbance value reaches the maximum; wherein, before the test, the spectrum scanning is performed to determine the specific values of the measurement wavelength and the reference wavelength, and then the relationship curve between the absorbance ΔA and the concentration C of the chloride ion standard solution is determined; the monochromatic light measurement wavelength range determined by the application is 400-450 nm, and the monochromatic light reference wavelength range is 560-600 nm;

[0105] B, determining the regression equation: taking the data of the ΔA-C standard curve as a basic database, determining the regression equation, the relative standard deviation, the recovery rate and the like, and combining with the above detection system, the online automatic detection of the chloride ion content can be realized;

[0106] C, analyzing the to-be-tested liquid: in the above determined wavelength range, the to-be-tested acid copper tank liquid is diluted and then added into the sample cell 122, and then the HNO3 solution, the emulsifier solution and the AgNO3 solution are sequentially added, and then the determination is performed through the colorimetric probe 12 after being placed for 15-30 min, and the first electric signal and the second electric signal of two different wavelengths are obtained, the absorbance difference ΔA of the first electric signal and the second electric signal is calculated, and then compared with the chloride ion standard curve (or brought into the regression equation), the concentration of the chloride ion in the diluted to-be-tested acid copper tank liquid is obtained, and the concentration of the chloride ion in the to-be-tested acid copper tank liquid is calculated according to the dilution multiple; then the concentration data of the chloride ion can be fed back to the control unit 2, compared and analyzed with the limit set by the control unit 2, and finally the analysis result is fed back to the dosing and supplementing unit 3 for the next operation.

[0107] In combination with the above detection system, the detection method of the application can realize automatic sampling and automatic analysis on one hand, and realizes unmanned automatic operation, saves the labor cost; on the other hand, the colorimetric probe and the control unit are used for automatic judgment, and the analysis result is more stable and reliable; in addition, the analysis frequency of the chloride ion content can also be greatly improved, and the normal progress of the electrolytic copper foil process is ensured.

[0108] According to the disclosure and teaching of the above description, those skilled in the art of the application can also make changes and modifications to the above embodiments. Therefore, the application is not limited to the above specific embodiments, and any obvious improvement, replacement or modification made by those skilled in the art on the basis of the application all belong to the protection scope of the application. In addition, although some specific terms are used in the specification, these terms are only for convenience of description and do not constitute any limitation on the application.

Claims

1. A detection system for detecting chloride ion content in an acid copper bath, characterized in that, Includes a detection unit, which includes: The reaction section is used to mix the copper acid bath solution with auxiliary reagents to obtain the copper acid bath solution to be tested. The colorimetric probe includes a light source, a sample cell, and a photoelectric receiving component arranged sequentially. The photoelectric receiving component includes a first photoelectric receiving component and a second photoelectric receiving component. After passing through the sample cell, the light from the light source is split into two different wavelengths and enters the first and second photoelectric receiving components respectively. The first photoelectric receiving component outputs a first electrical signal, and the second photoelectric receiving component outputs a second electrical signal, which is used to detect the concentration of chloride ions in the copper acid bath solution to be tested. Specifically, the copper acid bath solution to be tested is diluted and added to the sample cell. Then, HNO3 solution, emulsifier solution, and AgNO3 solution are added sequentially. The solution is allowed to stand for 15-30 minutes, and then the colorimetric probe is used to measure the concentration of chloride ions in the diluted copper acid bath solution to be tested. The first and second electrical signals output by the two different wavelengths are obtained. The absorbance difference ΔA between the first and second electrical signals is calculated and then compared with the chloride ion standard curve to obtain the concentration of chloride ions in the diluted copper acid bath solution to be tested. The concentration of chloride ions in the copper acid bath solution to be tested is calculated according to the dilution factor. The detection unit further includes a first sampling section and a second sampling section; wherein, the first sampling section is connected to the reaction section and is used to draw the copper acid bath solution into the reaction section; one end of the second sampling section is connected to the reaction section and the other end is connected to the sample cell in the colorimetric probe, and is used to draw the mixed copper acid bath solution to be tested in the reaction section into the sample cell of the colorimetric probe; the first sampling section includes a multi-channel valve group for switching between drawing the copper acid bath solution and auxiliary reagents; the reaction section further includes a stirring element for mixing the copper acid bath solution and auxiliary reagents; The detection unit also includes a first waste discharge component and a second waste discharge component; the first waste discharge component is connected to the reaction section and is used to discharge the waste liquid in the reaction section; the second waste discharge component is connected to the colorimetric probe and is used to discharge the waste liquid in the colorimetric probe; the detection system also includes a control unit and a dosing replenishment unit; the control unit is electrically connected to the colorimetric probe and the dosing replenishment unit respectively, and is used to feed back the result of the colorimetric probe to the dosing replenishment unit.

2. The detection system for detecting chloride ion content in acid copper bath solution according to claim 1, characterized in that, The first photoelectric receiving component includes a first monochromatic filter and a first photoelectric signal converter arranged sequentially. The first monochromatic filter is used to obtain the monochromatic light measurement wavelength, and the first photoelectric signal converter is used to receive the optical signal from the first monochromatic filter and convert it into a first electrical signal for output. The second photoelectric receiving component includes a second monochromatic filter and a second photoelectric signal converter arranged sequentially. The second monochromatic filter is used to obtain a monochromatic light reference wavelength, and the second photoelectric signal converter is used to receive the optical signal from the second monochromatic filter and convert it into a second electrical signal output.

3. The detection system for detecting chloride ion content in acid copper bath solution according to claim 2, characterized in that, The monochromatic light measurement wavelength range is 400~450nm; the monochromatic light reference wavelength range is 560~600nm.

4. The detection system for detecting chloride ion content in acid copper bath solution according to claim 1 or 2, characterized in that, It also includes an external signal terminal for outputting the first and second electrical signals to an external circuit.

5. A method for detecting chloride ion content in an acid copper bath, characterized in that, Includes the following steps: The copper acid bath solution to be tested is diluted and added to the sample cell. Then, HNO3 solution, emulsifier solution, and AgNO3 solution are added sequentially. After standing for 15-30 minutes, the solution is measured using a colorimetric probe to obtain a first electrical signal and a second electrical signal output at two different wavelengths. The absorbance difference ΔA between the first and second electrical signals is calculated and compared with the chloride ion standard curve to obtain the chloride ion concentration in the diluted copper acid bath solution. The chloride ion concentration in the copper acid bath solution is calculated based on the dilution factor. The detection system for detecting the chloride ion content in copper acid bath solution as described in any one of claims 1-4 is used.

6. The method for detecting chloride ion content in the acid copper bath according to claim 5, characterized in that, The method for preparing the chloride ion standard curve is as follows: First, using CuSO4·5H2O solution as the base liquid, prepare chloride ion standard solutions of different concentrations for later use; then, using the silver chloride turbidimetric method, measure the absorbance of the chloride ion standard solutions of different concentrations for light at the set measurement wavelength and reference wavelength, calculate the absorbance difference ΔA between the measurement wavelength and the reference wavelength, and prepare a standard curve of absorbance difference ΔA versus chloride ion concentration. After obtaining the concentration of chloride ions in the copper acid bath, it is compared with the set concentration limit, and the comparison result is fed back to the dosing replenishment unit through the signal external terminal of the colorimetric probe, so as to realize the online automatic detection of chloride ion content in the copper acid bath.

7. The method for detecting chloride ion content in acid copper bath solution according to claim 6, characterized in that, The concentration of the HNO3 solution is 1.4 g / cm³. 3 The emulsifier solution is 30% Triton X-100 or 30% ethylene glycol solution; the concentration of CuSO4·5H2O solution is 0.10 mol / L.

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