Method for determining trace elements in metallic manganese

Abstract

This application relates to a method for determining trace elements in metallic manganese. This method utilizes inductively coupled plasma mass spectrometry (ICP-MS) to determine trace elements in metallic manganese, achieving high sensitivity and accuracy in the detection of trace elements and improving the accuracy of analytical results. By employing matrix matching to eliminate interference, the method effectively reduces interference from other elements in the determination of trace elements, further enhancing the accuracy of the results. This method is applicable to the determination of trace elements in various types of metallic manganese samples, exhibiting broad applicability. Furthermore, the method's operation steps are simple and clear, easy to master, and readily applicable in practical work.

Description

Technical Field

[0001] This application relates to the field of trace element detection technology, and in particular to a method for determining trace elements in metallic manganese. Background Technology

[0002] With the continuous advancement of science and technology and the steady improvement of productivity, metallic manganese (Mn), with its core advantages of high purity and low impurities, has been widely and deeply applied in modern industrial systems, covering multiple key fields such as iron and steel smelting, non-ferrous metallurgy, electronics, chemical industry, environmental protection, food hygiene, welding electrode industry, and aerospace industry, becoming one of the important basic materials supporting the high-quality development of related industries. In the iron and steel smelting field, metallic manganese, as an indispensable raw material, has its impurity element content directly determining the purity and performance of the smelted product. This has a significant impact on key indicators such as strength, hardness, and toughness of steel products, and may even affect the processing and forming quality and safety of high-end steel. Therefore, accurate detection of the impurity element content in metallic manganese is of paramount importance for ensuring industrial production quality and promoting the upgrading of related industries.

[0003] Currently, inductively coupled plasma mass spectrometry (ICP-MS) has become one of the mainstream technologies in the field of trace element detection due to its significant advantages such as speed, simultaneous determination of multiple elements, wide linear range, high precision, and low detection limit. Existing literature (such as "Determination of Trace Elements in Electrolytic Manganese Metal by Inductively Coupled Plasma Mass Spectrometry") reports that this method can effectively achieve accurate determination of 13 trace elements, including Na, Mg, Ti, V, and Co, in electrolytic manganese metal. By optimizing instrument operating parameters and selecting appropriate isotopes and interference correction methods, mass spectrometry interference and matrix interference can be effectively overcome, meeting the detection requirements for these trace elements.

[0004] However, a search revealed that currently available domestic and international literature, industry standards, and patents do not address methods for determining trace elements such as Sn and Bi in metallic manganese. As industrial production demands increasingly higher purity levels for metallic manganese, the impact of trace impurities like Sn and Bi on the quality of subsequent products is becoming increasingly prominent. The gaps in existing detection technologies cannot meet the demands for comprehensive purity testing of metallic manganese in actual production, thus hindering the further development of related industries.

[0005] In view of this, it is necessary to design a method for determining trace elements in metallic manganese in order to solve the above problems. Summary of the Invention

[0006] This application provides a method for determining trace elements in metallic manganese, in order to solve the problem of the inability to accurately analyze the content of trace elements such as Sn and Bi in metallic manganese.

[0007] In a first aspect, this application provides a method for determining trace elements in metallic manganese, comprising the following steps: Provide manganese-containing sample solutions; Provide mixed standard solutions; Select the isotopes of the trace elements to be measured, and determine the intensity of the mixed standard solution using inductively coupled plasma mass spectrometry, and plot the calibration curve; The intensity of the manganese-containing sample solution was determined using the inductively coupled plasma mass spectrometry method; the content of trace elements in the manganese-containing sample solution was determined based on the calibration curve. The preparation steps of the manganese-containing sample solution include: placing the manganese-containing analyte in an acid solvent and heating it to dissolve it to obtain a first mixture; cooling the first mixture to 10°C~30°C and then diluting it with water to obtain the manganese-containing sample solution.

[0008] In some embodiments, in the manganese-containing sample solution, the volume ratio of the acid solvent, the mass of the manganese-containing analyte, and the volume of water is (18.0 mL~22.0 mL):1 g:(78 mL~82 mL); and / or, The acid solvent includes hydrochloric acid and nitric acid; the volume ratio of the hydrochloric acid to the nitric acid is 1:4; the concentration of the nitric acid is 1.42 g / mL; the concentration of the hydrochloric acid is 1.19 g / mL; and / or, The target temperature for heating is 230°C.

[0009] In some embodiments, the manganese-containing analyte comprises metallic manganese with a mass percentage of Mn ≥ 80%.

[0010] In some embodiments, the isotopes of the trace element to be measured include any one or more of Sn (118), Sb (121), Pb (208), and Bi (209).

[0011] In some embodiments, the preparation step of the mixed standard solution includes: providing several portions of matrix solution; and using a stepwise dilution method, adding trace element standard solutions of different contents to several portions of the matrix solution to obtain several portions of mixed standard solutions containing different trace element contents.

[0012] In some embodiments, the trace element standard solution includes any one or more of Sn standard solution, Sb standard solution, Pb standard solution, and Bi standard solution.

[0013] In some embodiments, the plurality of the mixed standard solutions include mixed standard solutions with any one or more trace element contents of 0, mixed standard solutions with any one or more trace element contents of 5 µg / g, mixed standard solutions with any one or more trace element contents of 10 µg / g, and mixed standard solutions with any one or more trace element contents of 35 µg / g.

[0014] In some embodiments, the trace elements contained in the mixed standard solution include any one or more of Sn, Sb, Pb, and Bi.

[0015] In some embodiments, the preparation step of the matrix solution includes: placing a certified standard material of high-purity manganese in an acid solvent and heating to dissolve it to obtain a second mixture; cooling the second mixture to 10°C~30°C and then diluting it with water to obtain a matrix solution; In the matrix solution, the volume ratio of the acid solvent, the mass of the certified reference material high-purity manganese, and the volume of water is (18.0 mL~22.0 mL): 1 g: (78 mL~82 mL); the mass percentage of Mn element in the certified reference material high-purity manganese is ≥99.999%; the volume of the manganese sample solution is the same as that of the matrix solution; the acid solvent includes hydrochloric acid and nitric acid; the volume ratio of hydrochloric acid and nitric acid is 1:4; the concentration of nitric acid is 1.42 g / mL; the concentration of hydrochloric acid is 1.19 g / mL. The target temperature for heating is 230°C.

[0016] In some embodiments, the method for plotting the calibration curve specifically includes: introducing the mixed standard solution into an inductively coupled plasma mass spectrometer in order of increasing concentration of trace elements through a sample introduction system, and measuring the intensity of the mixed standard solution; plotting several calibration curves with the intensity value of any trace element in the mixed standard solution as the ordinate and the content of any trace element in the mixed standard solution as the abscissa; the trace elements in the same calibration curve are the same.

[0017] The technical solutions provided in this application have the following advantages compared with the prior art: The method for determining trace elements in metallic manganese provided in this application utilizes inductively coupled plasma mass spectrometry (ICP-MS) to determine trace elements in metallic manganese. This method achieves high sensitivity and accuracy in the detection of trace elements, contributing to improved analytical results. By employing matrix matching to eliminate interference, the method effectively reduces interference from other elements in the determination of trace elements, further enhancing the accuracy of the results. This method is applicable to the determination of trace elements in various types of metallic manganese samples, exhibiting broad applicability. Furthermore, the method's operation steps are simple and clear, easy to master, and readily applicable in practical work. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 The Sn calibration curve provided in this application is shown; Figure 2 The Pb calibration curve provided in this application is shown. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0022] Various embodiments of this application may exist in the form of a range. It should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a rigid limitation on the scope of this application. Therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. In addition, whenever a numerical range is indicated in this application, it means including any referenced number (fraction or integer) within the indicated range. Unless otherwise specified, all raw materials, reagents, instruments, and equipment used in this application can be purchased commercially or prepared by existing methods. In this application, unless otherwise stated, directional terms such as "upper" and "lower" specifically refer to the drawing directions in the accompanying drawings. In addition, in this application, the terms "comprising," "including," etc., mean "including but not limited to." In this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, without necessarily requiring or implying any actual relationship or order between these entities or operations. In this application, "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. A and B can be singular or plural. In this application, "at least one" means one or more, and "more than one" means two or more. "At least one," "at least one of the following," or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, "at least one of a, b, or c," or "at least one of a, b, and c," can both represent: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can each be single or multiple.

[0023] This application provides a method for determining trace elements in metallic manganese, including the following steps: Step 1: Provide a manganese-containing sample solution; Step 2: Provide a mixed standard solution; Step 3: Select the isotopes of the trace elements to be measured, and determine the intensity of the mixed standard solution using inductively coupled plasma mass spectrometry, and plot the calibration curve; Step 4: Determine the intensity of the manganese-containing sample solution using the inductively coupled plasma mass spectrometry method; determine the content of trace elements in the manganese-containing sample solution based on the calibration curve; The preparation steps of the manganese-containing sample solution include: placing the manganese-containing analyte in an acid solvent and heating it to dissolve it to obtain a first mixture; cooling the first mixture to 10°C~30°C and then diluting it with water to obtain the manganese-containing sample solution.

[0024] The method for determining trace elements in metallic manganese provided in this application utilizes inductively coupled plasma mass spectrometry (ICP-MS) to determine trace elements in metallic manganese. This method achieves high sensitivity and accuracy in the detection of trace elements, contributing to improved analytical results. By employing matrix matching to eliminate interference, the method effectively reduces interference from other elements in the determination of trace elements, further enhancing the accuracy of the results. This method is applicable to the determination of trace elements in various types of metallic manganese samples, exhibiting broad applicability. Furthermore, the method's operation steps are simple and clear, easy to master, and readily applicable in practical work.

[0025] As an optional implementation, in this embodiment of the application, the volume ratio of the acid solvent, the mass of the manganese-containing analyte, and the volume of water in the manganese-containing sample solution is (18.0 mL~22.0 mL):1 g:(78 mL~82 mL). Preferably, the volume ratio of the acid solvent, the mass of the manganese-containing analyte, and the volume of water in the manganese-containing sample solution is (19.5 mL~20.5 mL):1 g:(79.5 mL~80.5 mL).

[0026] In the embodiments of this application, the acid solvent includes hydrochloric acid and nitric acid; the volume ratio of hydrochloric acid to nitric acid is 1:4; the concentration of nitric acid is 1.42 g / mL; and the concentration of hydrochloric acid is 1.19 g / mL.

[0027] Therefore, using a mixture of hydrochloric acid and nitric acid can accelerate the dissolution of manganese-containing analytes and speed up the detection process.

[0028] In the embodiments of this application, all nitric acid was of analytical grade and purchased from Sinopharm Chemical Reagent Co., Ltd. All water was 18.25 MΩ·cm ultrapure water obtained from the ApoGen laboratory ultrapure water system.

[0029] In this embodiment, the target heating temperature is 230°C. The heating method includes heating with an electric heating plate.

[0030] The dissolution time is 2 min to 4 min; preferably, the dissolution time is 2.5 min to 3.5 min.

[0031] As an optional implementation, in this embodiment of the application, the manganese-containing test substance includes metallic manganese with a mass percentage of Mn ≥ 80%.

[0032] As an optional implementation, in this embodiment of the application, the isotopes of the trace elements to be tested include any one or more of Sn (118), Sb (121), Pb (208), and Bi (209).

[0033] Thus, the intensity of mixed standard solutions can be accurately determined using inductively coupled plasma mass spectrometry.

[0034] As an optional implementation, in this embodiment of the application, the preparation step of the mixed standard solution includes: providing several portions of matrix solution; and using a stepwise dilution method, adding different amounts of trace element standard solutions to several portions of the matrix solution to obtain several portions of mixed standard solutions containing different amounts of trace elements.

[0035] Thus, by preparing trace element concentration gradient solutions through stepwise dilution and measuring the strength of the calibration series solutions, the accurate plotting of the calibration curve can be ensured, which helps to improve the reliability of the measurement results.

[0036] As an optional implementation, in this embodiment of the application, the trace element standard solution includes any one or more of Sn standard solution, Sb standard solution, Pb standard solution, and Bi standard solution. The trace element standard solution is selected from the multi-element standard solutions in "China Steel Research Institute NACK GBW(E)03902 NCS 141007".

[0037] As an optional implementation, in the embodiments of this application, the plurality of mixed standard solutions include mixed standard solutions with any one or more trace element contents of 0, mixed standard solutions with any one or more trace element contents of 5µg / g, mixed standard solutions with any one or more trace element contents of 10µg / g, and mixed standard solutions with any one or more trace element contents of 35µg / g.

[0038] As an optional implementation, in the embodiments of this application, the trace elements contained in the mixed standard solution include any one or more of Sn, Sb, Pb, and Bi.

[0039] As an optional implementation, in this embodiment of the application, the preparation steps of the matrix solution include: placing certified standard material high-purity manganese in an acid solvent and heating to dissolve it to obtain a second mixture; cooling the second mixture to 10°C~30°C and then diluting it with water to obtain the matrix solution; In the matrix solution, the volume ratio of the acid solvent, the mass of the certified reference material high-purity manganese, and the volume ratio of the water is (18.0 mL~22.0 mL): 1 g: (78 mL~82 mL); the mass percentage of Mn element in the certified reference material high-purity manganese is ≥99.999%; the certified reference material high-purity manganese is in powder form; the certified reference material high-purity manganese is purchased from Steel Research Institute Nake Testing Technology Co., Ltd.; the volume of the manganese sample solution is the same as that of the matrix solution; the acid solvent includes hydrochloric acid and nitric acid; the volume ratio of hydrochloric acid to nitric acid is 1:4; the concentration of nitric acid is 1.42 g / mL; the concentration of hydrochloric acid is 1.19 g / mL; The target temperature for heating is 230°C.

[0040] As an optional implementation, in this embodiment of the application, the method for plotting the calibration curve specifically includes: introducing the mixed standard solution into the inductively coupled plasma mass spectrometer in order of increasing concentration of trace elements through a sample introduction system, measuring the intensity of the mixed standard solution, and plotting the calibration curve.

[0041] As an optional implementation, in this embodiment of the application, the operating parameters of the inductively coupled plasma mass spectrometer include: power of 1365W; cooling gas flow rate of 14.0L / min; auxiliary gas flow rate of 0.9L / min; nebulizer flow rate of 0.75L / min; pump speed of 50r / min; number of scans of 50; residence time of 40ms; total acquisition time of 70s; and interval rinsing time of 50s.

[0042] Therefore, by optimizing the operating parameters of the inductively coupled plasma mass spectrometer, the measurement accuracy of the instrument can be improved, thereby increasing the accuracy of trace element determination results.

[0043] The present application is further illustrated below with reference to specific embodiments. Experimental methods in the following embodiments that do not specify specific conditions are generally determined according to national standards. If no corresponding national standard exists, then generally accepted international standards, conventional conditions, or conditions recommended by the manufacturer are followed.

[0044] Example 1 Example 1 provides a method for determining trace elements in metallic manganese, comprising the following steps: Step 1: Provide a manganese-containing sample solution; The preparation steps of the manganese-containing sample solution include: placing 0.10 g ± 0.0001 g of electrolytic manganese (manganese-containing analyte) in 2 mL of acid solvent, heating to 230 °C to dissolve it, and obtaining a first mixture; cooling the first mixture to 20 °C, transferring it to a 100 mL volumetric flask, diluting it with water to a final volume of 100 mL, and obtaining the manganese-containing sample solution; the mass percentage of Mn element in the manganese-containing analyte is 80%~99.99%; The acid solvents include hydrochloric acid and nitric acid; the volume ratio of hydrochloric acid to nitric acid is 1:4; the concentration of nitric acid is 1.42 g / mL; and the concentration of hydrochloric acid is 1.19 g / mL. Step 2: Provide a mixed standard solution; The preparation steps of the mixed standard solution include: providing four matrix solutions; using a stepwise dilution method, adding different amounts of trace element standard solutions to the four matrix solutions respectively to obtain four mixed standard solutions containing different amounts of trace elements; the trace element standard solutions include Sn standard solution, Sb standard solution, Pb standard solution, and Bi standard solution; The trace elements contained in the mixed standard solution include Sn, Sb, Pb, and Bi; The four mixed standard solutions include a mixed standard solution with a trace element content of 0, a mixed standard solution with a trace element content of 5 µg / g (Sn, Sb, Pb, and Bi are all 5 µg / g), a mixed standard solution with a trace element content of 10 µg / g (Sn, Sb, Pb, and Bi are all 10 µg / g), and a mixed standard solution with a trace element content of 35 µg / g (Sn, Sb, Pb, and Bi are all 35 µg / g). The preparation steps of the matrix solution include: placing 0.10 g ± 0.0001 g of certified standard high-purity manganese in an acid solvent and heating it to 230 °C to dissolve it, thereby obtaining a second mixture; cooling the second mixture to 20 °C and then diluting it with water to a final volume of 100 mL to obtain the matrix solution; The certified reference material high-purity manganese contains 99.99% Mn by mass; the certified reference material high-purity manganese is in powder form; the acid solvents include hydrochloric acid and nitric acid; the volume ratio of hydrochloric acid to nitric acid is 1:4; the concentration of nitric acid is 1.42 g / mL; the concentration of hydrochloric acid is 1.19 g / mL. Step 3: After setting the working conditions, the isotopes of the trace elements to be measured are optimally selected by tuning the instrument, and the intensity of the mixed standard solution is determined by inductively coupled plasma mass spectrometry, and a calibration curve is plotted. The isotopes of the trace elements to be measured include Sn (118), Sb (121), Pb (208), and Bi (209). The specific method for plotting the calibration curve includes: introducing the mixed standard solution into the inductively coupled plasma mass spectrometer sequentially according to the concentration of trace elements from low to high through the injection system, and measuring the intensity of the mixed standard solution; subtracting the intensity of the zero-concentration solution from the measured intensity value of the mixed standard solution to obtain the net intensity; plotting the content of the analyte (µg / g) on ​​the x-axis and the net intensity value on the y-axis, and plotting the calibration curve. The results of the linear regression equation are shown in Table 1, where some calibration curves are shown below. Figure 1 and Figure 2 As shown; Step 4: After setting the working conditions, optimize the selection of Sn(118), Sb(121), Pb(208) and Bi(209) isotopes by tuning and adjusting the instrument, and measure the mixed standard solution series and manganese-containing sample solution in sequence. Determine the content of Sn, Sb, Pb and Bi elements in the manganese-containing sample solution according to the calibration curve drawn in Step 3. The operating parameters of the inductively coupled plasma mass spectrometer include: power of 1365W; cooling gas flow rate of 14.0L / min; auxiliary gas flow rate of 0.9L / min; nebulizer flow rate of 0.75L / min; pump speed of 50r / min; number of scans of 50; residence time of 40ms; total acquisition time of 70s; and interval rinsing time of 50s.

[0045] Example 2 Example 2 provides a method for determining trace elements in metallic manganese. The difference between Example 1 and Example 2 is that the manganese-containing analyte used in preparing the manganese-containing sample solution is different. The manganese-containing analyte used in Example 2 is high-purity manganese, and the percentage of Mn element in high-purity manganese is 80%~99.99% by mass.

[0046] The remaining steps are the same as in Example 1, and will not be repeated here.

[0047] Test results 1. Limit of detection and limit of quantitation: Eleven parallel determinations were performed using a zero-concentration blank solution with a calibration curve consistent with the matrix of the sample solution. The standard deviation (SD) was calculated, and the method detection limit was calculated based on the standard deviation. The detection limit, quantitation limit, and linear correlation coefficient of Examples 1-2 are shown in Table 1.

[0048] Table 1. Linear equations of calibration curves and method detection limits

[0049] 2. Precision test The relative standard deviation (RSD) can be used to characterize the precision of a method, and the relative standard deviation is the in-laboratory coefficient of variation. Referring to Appendix F of GB / T 27404-2008, the in-laboratory coefficient of variation is shown in Table 2. In Examples 1 and 2, 12 parallel samples were weighed and measured respectively, and the precision experimental results are shown in Table 3. The relative standard deviations were all within the standard range, indicating that the method is accurate and reliable.

[0050] Table 2. In-laboratory coefficient of variation

[0051] Table 3 Precision experimental parameters of Examples 1-2

[0052] Comparative Example 1 Comparative Example 1 provides a method for determining trace elements in metallic manganese. The difference between Comparative Example 1 and Example 1 is the volume of the acid solvent. In Comparative Example 1, when the manganese-containing analyte is placed in the acid solvent, the volume of the acid solvent used is 4 mL.

[0053] The remaining steps are the same as in Example 1, and will not be repeated here.

[0054] In addition, spiked recovery experiments were conducted using unknown samples. Referring to Appendix F of GB / T 27404-2008, the recovery rate ranged from 90% to 110% when the content of the analyte was 1 mg / kg to 100 mg / kg, and from 80% to 120% when the content of the analyte was less than 0.1 mg / kg. Examples 1 and 2 and the provided detection method were evaluated. In this experiment, six samples from Examples 1 and 2 were weighed, and standard solutions of Sn, Sb, Pb, and Bi with the contents shown in Table 4 were added respectively to conduct spiked recovery experiments. As shown in Table 4, when the contents of the analyte Sn, Sb, and Pb are 1 mg / kg to 100 mg / kg, the spiked recoveries are in the range of 91.38% to 109.00%. When the contents of the analyte Bi are less than 0.1 mg / kg, the spiked recoveries are in the range of 72.5% to 118.38%, which meet the analytical requirements. This method can be used for the determination of trace elements in metallic manganese.

[0055] However, when 4 mL of nitric acid was used to dissolve the sample solution in Comparative Example 1, the spiked recovery rate was significantly reduced.

[0056] Table 4 Spiking recovery tests of samples dissolved with different acid concentrations

[0057] In summary, this invention provides a method for determining trace elements in metallic manganese. By employing inductively coupled plasma mass spectrometry (ICP-MS), the method achieves high sensitivity and accuracy in detecting trace elements, thus improving the accuracy of analytical results. Furthermore, the use of matrix matching to eliminate interference effectively reduces the influence of other elements on the determination of trace elements, further enhancing the accuracy of the results. This method is applicable to the determination of trace elements in various types of metallic manganese samples, exhibiting broad applicability. Moreover, the method is simple and straightforward to operate, easy to master, and readily applicable in practical work.

[0058] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed in this application.

Claims

1. A method for determining trace elements in metallic manganese, characterized in that, Includes the following steps: Provide manganese-containing sample solutions; Provide mixed standard solutions; Select the isotopes of the trace elements to be measured, and determine the intensity of the mixed standard solution using inductively coupled plasma mass spectrometry, and plot the calibration curve; The strength of the manganese-containing sample solution was determined using the inductively coupled plasma mass spectrometry method described above. The content of trace elements in the manganese-containing sample solution was determined based on the calibration curve. The preparation steps of the manganese-containing sample solution include: placing the manganese-containing analyte in an acid solvent and heating it to dissolve it to obtain a first mixture; cooling the first mixture to 10°C~30°C and then diluting it with water to obtain the manganese-containing sample solution.

2. The method for determining trace elements in metallic manganese according to claim 1, characterized in that, In the manganese-containing sample solution, the volume ratio of the acid solvent, the mass of the manganese-containing analyte, and the volume of water is (18.0 mL~22.0 mL): 1 g: (78 mL~82 mL); and / or, The acid solvent includes hydrochloric acid and nitric acid; the volume ratio of the hydrochloric acid to the nitric acid is 1:4; the concentration of the nitric acid is 1.42 g / mL; the concentration of the hydrochloric acid is 1.19 g / mL; and / or, The target temperature for heating is 230°C.

3. The method for determining trace elements in metallic manganese according to claim 1, characterized in that, The manganese-containing test substance includes metallic manganese with a mass percentage of Mn ≥ 80%.

4. The method for determining trace elements in metallic manganese according to claim 1, characterized in that, The isotopes of the trace elements to be tested include any one or more of Sn (118), Sb (121), Pb (208), and Bi (209).

5. The method for determining trace elements in metallic manganese according to claim 4, characterized in that, The preparation steps of the mixed standard solution include: providing several portions of matrix solution; and using a stepwise dilution method, adding different amounts of trace element standard solution to the several portions of matrix solution to obtain several portions of mixed standard solution containing different trace element contents.

6. The method for determining trace elements in metallic manganese according to claim 5, characterized in that, The trace element standard solution includes any one or more of Sn standard solution, Sb standard solution, Pb standard solution, and Bi standard solution.

7. The method for determining trace elements in metallic manganese according to claim 6, characterized in that, The plurality of the mixed standard solutions include mixed standard solutions with any one or more trace element contents of 0, mixed standard solutions with any one or more trace element contents of 5 µg / g, mixed standard solutions with any one or more trace element contents of 10 µg / g, and mixed standard solutions with any one or more trace element contents of 35 µg / g.

8. The method for determining trace elements in metallic manganese according to claim 7, characterized in that, The trace elements contained in the mixed standard solution include any one or more of Sn, Sb, Pb, and Bi.

9. The method for determining trace elements in metallic manganese according to claim 5, characterized in that, The preparation steps of the matrix solution include: placing certified standard material high-purity manganese in an acid solvent and heating to dissolve it to obtain a second mixture; cooling the second mixture to 10℃~30℃ and then diluting it with water to obtain the matrix solution; In the matrix solution, the volume ratio of the acid solvent, the mass of the certified reference material high-purity manganese, and the volume of water is (18.0 mL~22.0 mL): 1 g: (78 mL~82 mL); the mass percentage of Mn element in the certified reference material high-purity manganese is ≥99.99%; the volume of the manganese sample solution is the same as that of the matrix solution; the acid solvent includes hydrochloric acid and nitric acid; the volume ratio of hydrochloric acid and nitric acid is 1:4; the concentration of nitric acid is 1.42 g / mL; the concentration of hydrochloric acid is 1.19 g / mL. The target temperature for heating is 230°C.

10. The method for determining trace elements in metallic manganese according to any one of claims 1 to 9, characterized in that, The method for plotting the calibration curves specifically includes: introducing the mixed standard solution into the inductively coupled plasma mass spectrometer in order of increasing concentration of trace elements through the sample introduction system, and measuring the intensity of the mixed standard solution; plotting several calibration curves with the intensity value of any trace element in the mixed standard solution as the ordinate and the content of any trace element in the mixed standard solution as the abscissa; the trace elements in the same calibration curve are the same.

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