Rapid determination method for impurities in electrolytic copper foil electrolyte

Abstract

The invention relates to a rapid determination method for impurities in an electrolytic copper foil electrolyte. The rapid determination method comprises the following steps: (1) preparing metal ion standard solutions A with different concentrations; (2) preparing a metal ion standard solution B; (3) testing the metal ion standard solution in the step (1) by using an x-fluorescence spectrophotometer, inputting the information of the metal ion content A in the step (1), and establishing a detection standard curve; and (4) testing by using the metal ion standard solution B in the step (2) and the standard curve in the step (3). The method is high in standard recovery level and more accurate in measured data, and has a good application prospect.

Description

Technical Field

[0001] The present invention belongs to the technical field of electrolyte detection, and particularly relates to a rapid determination method for impurities in the electrolyte of electrolytic copper foil. Background Art

[0002] Sulfuric acid and metallic copper are important raw materials for the electrolyte. During the production process, trace metal impurities are inevitably introduced into it. Moreover, the pipelines and storage containers used in the preparation process of the electrolyte are mostly metal products, and there are various sources of metal impurity introduction. The presence of metal impurities in the electrolyte will affect the performance of electrolytic copper foil. At present, ICP or AAS is mainly used to determine the content of non-copper metal impurities in the electrolyte in the industry. Due to its high copper content and relatively wide distribution of different impurity element contents, a series of dilutions are required before the detection of samples. And due to its high copper content, the matrix effect is obvious, which is likely to cause inaccurate detection data. Therefore, it is of great significance to develop a simple, convenient, rapid and accurate method for determining impurities in the electrolyte of electrolytic copper foil.

[0003] Since the content of trace metal impurities in the electrolyte is low, at the ppm level, ICP is mainly used for detection at present. Patent CN117269154A proposes a method for detecting impurities in the electrolyte. After the electrolyte is digested, ICP is used for quantitative analysis. Using ICP to determine the electrolyte has the problems of obvious matrix effect and different contents of different trace metal elements. It is necessary to perform distributed dilution before detection. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a rapid determination method for impurities in the electrolyte of electrolytic copper foil, which has small test background interference, simple sample treatment, and rapid and accurate testing.

[0005] The present invention provides a rapid determination method for impurities in the electrolyte of electrolytic copper foil, including the following steps: (1) Prepare a series of metal ion standard solutions A with the same copper content, sulfuric acid content, chloride ion content and the same matrix; (2) Prepare a series of metal ion standard solutions B with the same concentration of metal ions and a gradient of copper content, sulfuric acid content and chloride ion content; (3) Use the metal ion standard solution A in step (1) to test with an X-ray fluorescence spectrometer, input the information of the metal ion content in step (1), and establish a detection standard curve; (4) Use the metal ion standard solution B in step (2) and perform tests using the standard curve in step (3) (to further explore the influence of the matrix effect (sulfuric acid - copper sulfate - chloride ions at different concentrations) on the detection results of non - copper metal impurities in the copper - containing electrolyte), and establish a regression curve for the corresponding metal ion matrix correction, and that's it.

[0006] Preferably, the metal ions in step (1) include one or more of Zn, Cr, Ni, Co, Fe, As, and Pb.

[0007] Preferably, the copper content in the metal ion standard solution A in step (1) is 40 - 60 g / L, the sulfuric acid content is 60 - 160 g / L, the chloride ion concentration is 10 - 50 ppm, and the concentration of various metal ions is 0 - 1000 ppm but not all 0.

[0008] Preferably, the metal ion standard solution A in step (1) is prepared using its analytical - grade metal salts, analytical - grade sulfuric acid solution, and analytical - grade hydrochloric acid with pure water as the dispersion medium.

[0009] Preferably, the copper content in the metal ion standard solution B in step (2) is 10 - 70 g / L, the sulfuric acid content is 90 - 110 g / L, the chloride ion concentration is 30 - 40 ppm, and the concentration of various metal ions is 10 - 500 ppm.

[0010] Preferably, the correlation determination coefficient r2 of the detection standard curve in step (3) is ≥ 0.999.

[0011] Preferably, the correlation determination coefficient r2 of the regression curve in step (4) is ≥ 0.999, and the standard addition method is used to further verify the detection data, and its spike recovery rate is between 95% and 105%.

[0012] Beneficial effects By exploring the influence of different contents of the main components of the electrolyte, copper, sulfuric acid, and chloride ions, on the detection of non - metal impurities, the present invention obtains the corresponding regression curve. Based on the detection data of the X - ray fluorescence spectrometer, the detection data can be further corrected to obtain more accurate data. By studying the specific influence of the matrix effect on the detection of electrolyte impurities, the content range of each element in this determination curve is relatively wide, without the need to gradually dilute the sample to be measured, the operation is simple and convenient, the detection results are rapid and accurate. By further verifying the sample to be measured using the standard addition method, its spike recovery level is high, and the measured data is more accurate, having good application prospects. Specific Embodiments

[0013] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application.

[0014] Example 1 (1) Prepare a metal ion standard solution with a copper content of 60 g / L, a sulfuric acid content of 60 g / L, a chloride ion content of 40 ppm, and the concentration gradients of metal ions such as Zn, Cr, Ni, Co, Fe, As, and Pb configured using analytical pure grade drugs are 0 ppm, 100 ppm, 200 ppm, and 1000 ppm respectively. Use an x-ray fluorescence spectrometer to establish a detection standard curve with a correlation coefficient r≥0.999.

[0015] (2) Configure the following samples to study the influence of different contents of the main components of the electrolyte solution, namely copper, sulfuric acid, and chloride ions, on the results of detecting non-metal impurities. Measure them according to the measurement curve in step (1) to obtain the detection-related calibration regression curves of each element under different bases.

[0016] Zn calibration = 102.64 - 2.5375 * copper content + 0.175 * chloride ion content; Cr calibration = 201.2 - 2.578 * copper content - 0.0521 * chloride ion content * acid content; Fe calibration = -135.278 + 0.237 * acid content + 0.00214 * chloride ion content * copper content; Fe calibration = -102.278 + 0.237 * acid content + 0.00214 * chloride ion content * copper content; As calibration = 1.02 - 0.00014 * chloride ion content * copper content + 0.00011 * copper content * acid concentration; Pb calibration = 2.021 - 0.01945 * acid content + 0.05549 * copper content; Co calibration = -102.278 + 0.225 * acid content + 0.0014 * chloride ion content * copper content.

[0017] (3) Take electrolyte solutions from different groups on-site. After diluting them by an appropriate multiple with deionized water, use an X-ray fluorescence spectrometer to measure non-copper metal impurities, use a potentiometric titrator to measure the copper content, acid content, and chloride ion content of the solution to be measured, and use the standard addition method to further verify the measurement results. The results are as follows: In Sample No. 1, spiking determination was carried out on non-copper metal impurities in the target product, and the spiking recovery rate was calculated. The measurement results are as follows: Judging from the above measurement results, the detection method provided by the present invention is very accurate and reliable for the detection of non-copper metal impurities, meeting the requirements for the determination of sample solutions.

Claims

1. A rapid determination method for impurities in the electrolyte of electrolytic copper foil, comprising the following steps: (1) Prepare a series of metal ion standard solutions A with the same copper content, sulfuric acid content, chlorine ion content, and the same substrate but different concentrations; (2) Prepare a series of metal ion standard solutions B with the same concentration of metal ions, and the copper content, sulfuric acid content, and chlorine ion content showing a gradient; (3) Use the metal ion standard solution A in step (1) to conduct tests with an X-ray fluorescence spectrometer, input the information of the metal ion content in step (1), and establish a detection standard curve; (4) Use the metal ion standard solution B in step (2), conduct tests using the standard curve in step (3), and establish a regression curve for the correction of the corresponding metal ion substrate, and that's it.

2. The rapid determination method according to claim 1, characterized in that: The metal ions in step (1) include one or several of Zn, Cr, Ni, Co, Fe, As, and Pb.

3. The rapid determination method according to claim 1, characterized in that: In the metal ion standard solution A in step (1), the copper content is 40 - 60 g / L, the sulfuric acid content is 60 - 160 g / L, the chlorine ion concentration is 10 - 50 ppm, and the concentration of various metal ions is 0 - 1000 ppm but not all are 0.

4. The rapid determination method according to claim 1, characterized in that: In the metal ion standard solution B in step (2), the copper content is 10 - 70 g / L, the sulfuric acid content is 90 - 110 g / L, the chlorine ion concentration is 30 - 40 ppm, and the concentration of various metal ions is 10 - 500 ppm.

5. The rapid determination method according to claim 1, wherein: The correlation determination coefficient r2 of the detection standard curve in step (3) is ≥ 0.

999.

6. The rapid determination method according to claim 1, wherein: The correlation determination coefficient r2 of the regression curve in step (4) is ≥ 0.999, and the standard addition method is used to further verify the detection data, and its spike recovery rate is 95 - 105%.

Images