XRF (X-Ray Fluorescence) detection method for analyzing content of phosphorus element in iron phosphate analysis

Abstract

The invention discloses an XRF (X-Ray Fluorescence) detection method for analyzing the content of a phosphorus element in iron phosphate analysis, which comprises the following steps: S1, preparing an iron phosphate standard sample, titrating the content of the iron element and the phosphorus element in the iron phosphate standard sample, and drawing a phosphorus and iron content standard curve of the iron phosphate standard sample; in the used iron phosphate standard sample, the content range of Fe is 36.10 to 36.50 percent, and the content range of P is 20.5 to 21.00 percent; s2, after the bottom of a cup body of the steel cup is sleeved with a sample preparation film, a plastic lantern ring is arranged in a sleeving mode to press the periphery of the sample preparation film, the sample preparation film is flatly laid on the bottom face of the cup body, and after a to-be-detected sample with the volume 1 / 10 of the total volume of the cup body is filled, the to-be-detected sample is pressed; and S3, selecting an XRF analyzer with the power of 2.5 MPA and the detector resolution of less than or equal to 125 eV for setting, performing quality control sample analysis and data compensation after curve correction, and performing sample analysis on the to-be-measured pressure sample. The method is high in treatment efficiency, high in detection result accuracy and free of boric acid interference, boric acid waste does not need to be treated, and a detected sample can be recycled.

Description

Technical Field

[0001] The present application relates to the technical field of iron phosphate analysis, and in particular to an XRF detection method for analyzing phosphorus content in iron phosphate analysis. Background Art

[0002] Most of the analysis processes of ferric phosphate analysis results are based on the traditional potassium dichromate titration of iron and quinoline molybdenum copper precipitation method to analyze the phosphorus content in the product. However, these methods have low detection efficiency and low accuracy of test results, and cannot meet the needs of processing large quantities of samples during large-scale production.

[0003] X-ray fluorescence spectrometry (XRF analysis) is a non-destructive analysis technique used to determine the elemental composition of materials. It determines the chemical properties of samples by analyzing the fluorescent (or secondary) X-rays scattered by the sample when it is excited by a primary X-ray source. This method has high accuracy and processing efficiency.

[0004] Most of the samples used in existing XRF analysis are prepared in the traditional boric acid cake method. Boric acid cakes are made by adding boric acid to the top and bottom of the sample and then pressing it. However, there are problems such as poor uniformity of boric acid laying and excessive amount of boric acid added locally. After being pressed, it squeezes into the sample, resulting in low accuracy of the test results. Moreover, after adding boric acid, other elements are mixed into the sample and it cannot be directly reused. If it needs to be reused, it is necessary to separate and extract the boron element, which cannot achieve environmental protection, high efficiency, low cost and clean analysis of iron phosphate.

[0005] The information disclosed in the background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0006] In response to the above technical problems, the present application provides an XRF detection method for analyzing the phosphorus content in iron phosphate analysis. The method has high processing efficiency and high accuracy of detection results, no boric acid interference, no need to deal with boric acid waste, and the samples can be recovered and reused after detection.

[0007] The present application provides an XRF detection method for analyzing phosphorus content in iron phosphate analysis, comprising the following steps:

[0008] The following steps are involved:

[0009] Step S1: preparing a standard ferric phosphate sample, titrating the iron and phosphorus contents in the obtained standard ferric phosphate sample, and using the obtained contents as the abscissa value of the phosphorus and iron content standard curve of the standard ferric phosphate sample; the Fe content in the standard ferric phosphate sample used is in the range of 36.10-36.50%, and the P content is in the range of 20.5-21.00%;

[0010] Step S2: After a sample-preparing film is sleeved on the bottom of the cup body of the steel cup, a plastic sleeve ring is sleeved to press the periphery of the sample-preparing film, and the sample-preparing film is laid flat on the bottom surface of the cup body, and the sample to be tested is filled with 1 / 10 of the total volume of the cup body and then pressed; the sample to be tested is the product to be tested or a standard iron phosphate sample;

[0011] Step S3: Select an XRF analyzer with a power of 2.5 MPA and a detector resolution of ≤125 eV for setting, perform quality control sample analysis and data compensation after curve calibration, perform sample analysis on the pressure sample to be tested, and obtain the XRF test result. The XRF test result of the standard iron phosphate sample is used as the ordinate value of the standard curve of the phosphorus and iron contents of the standard iron phosphate sample, and the standard curves of the phosphorus and iron contents of the standard iron phosphate sample are drawn respectively;

[0012] Step S4: The average of the two tests of the parallel sample is added and subtracted from the compensation value of the standard sample on the day (quality control sample), and the result of the test sample on the day is calculated. The result of the test sample on the day = the manual test result of the standard sample ± the XRF test result of the standard sample on the day. The manual test result is the phosphorus and iron content in the sample determined by titration.

[0013] Preferably, the preparation of the pressure sample to be tested in step S2 comprises the following steps:

[0014] Step S21: selecting an iron phosphate sample having the same matrix as the standard sample for analysis, and testing a parallel sample;

[0015] Step S22: Cover the side of the stainless steel sample cup with a smaller diameter with a sample preparation film, fix it with a plastic ring, and ensure that the sample preparation film is flat and wrinkle-free;

[0016] Step S23: Return the electronic balance to zero, add 2.5±0.01 g of material into the stainless steel sample cup with a stainless steel spoon, gently shake the material in the sample cup to make it flat and loose, and gently rotate the stainless steel inner core with vaseline lubricant downward;

[0017] Step S24: Adjust the pressure of the sample pressing machine to 2.5 mPA to perform the sample pressing operation. After the sample pressing is completed, wait for 30 seconds to remove the sample to obtain the sample to be tested.

[0018] Preferably, the "setting" in step S3 includes the following steps:

[0019] Step S311: Before measuring, select "Add curve" and add a curve name under Curve name, select "FePO4-CP" in the material selection, enter the calibration curve name with the same name as the curve in "Add calibration center", and select Fe and P elements when entering the required elements;

[0020] Step S312: Click the keyboard "whiteboard", select "Accessoriees", select "File Manager", select "gitee", select "Allcurves", copy the existing solid parameters and paste them to the new curve, then check Apply...., select "Overwrite" to complete the curve parameter update;

[0021] Step S313: Select "Settings" in the XRF instrument measurement, select the established new curve "FePO4-CP" parameters in the curve, and select the calibration to test two sets of data in the "Defaulf" state;

[0022] Step S314: In the "Defaulf" state of the new curve in the "Curve" mode of the instrument, select "Set", check the analysis quality control sample number in the Fe P box, click "Add", enter the sample test results analyzed by multiple people in the same laboratory and converted into ppm in the Fe and P boxes, and enter "0" for "Correction Si", "Original Si" and "CR-K", confirm and complete the curve calibration setting and calibrate;

[0023] Step S315: Select "Settings" in the instrument measurement, select Analyze 2 times under the newly created curve such as "FePO4-CP" and calibration "Defaulf", and measure the Y-axis result of the required curve standard sample.

[0024] Step S316: Select the scatter plot in the table to make a standard curve, and calculate the a and b values ​​of the linear regression of the curve according to the instrument analysis results. Select "Manually set calibration parameters" in the "Open" of the current curve and enter the "a value and b×10000 (ppm) value. After confirmation, complete the setting of the standard curve.

[0025] Preferably, the "curve correction" in step S3 includes the following steps: Curve correction for the day: select the required curve in "Test" and complete the interface switching in the "Defaulf" state, select "Set" in "Curve" and confirm the completion of the curve correction for the day.

[0026] Preferably, the "quality control sample analysis and data compensation" in step S3 includes the following steps:

[0027] Step S321: Select 2 quality control samples (standard samples) in the required curve such as (FePO4-CP) and select the same name as the curve in the "Calibration" box of the test interface, such as (FePO4-CP), set the number of tests in the analysis sample box and select the automatic analysis mode to perform standard sample detection and analysis;

[0028] Step S321: Compare the test value of the day in step S321 with the standard sample (three consecutive test results by different people in the same laboratory), and calculate the value that needs to be compensated on the day.

[0029] Preferably, the pressing machine includes: a bracket, a mounting platform, a screw, a pressing head, a mounting platform, a handle, and a base; the bracket is installed on the base, and the mounting platform is arranged in the central area of ​​the base; the screw is connected to the center thread of the bracket; a handle is arranged at the top of the screw; a pressing head is arranged at the bottom of the screw; the central axis of the screw coincides with the mounting platform and the base.

[0030] Preferably, the stainless steel cup comprises: an inner core, a cup body, and a plastic sleeve; the interior of the cup body is connected; a sample-making film is laid on the bottom of the cup body, and the periphery of the sample-making film is covered by the plastic sleeve and pressed on the outer wall of the bottom of the cup body;

[0031] After the sample to be tested is filled in the cup body, one end of the inner core is inserted into the cup body, and the top of the inner core is extended out of the cup body and abuts against the lower pressing head of the sample pressing machine.

[0032] The beneficial effects of this application include:

[0033] 1) The XRF detection method for analyzing phosphorus content in iron phosphate analysis provided by the present application uses a stainless steel cup to press the sample to be tested and then measure it. No other substances need to be added. The sample is easy to handle after the test. The analysis using a stainless steel cup has the advantages of strong stability, high precision, high efficiency, low cost and environmental protection. Compared with the traditional boric acid press cake analysis of iron phosphate, the stainless steel cup does not generate waste and can be used repeatedly for a long time. During use, the sample only needs to be physically squeezed without adding other substances, and it is not easy to introduce impurities. The above properties make the stainless steel cup used in iron phosphate analysis more practical, more efficient, and more easily widely used.

[0034] 2) The XRF detection method for analyzing the phosphorus content in iron phosphate analysis provided in the present application uses a stainless steel sample cup to load the sample, which can avoid the introduction of impurities into the sample that may cause errors in the test results and improve the accuracy and reliability of the test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic diagram of an XRF detection method for analyzing phosphorus content in iron phosphate analysis in at least one embodiment provided in the present application;

[0036] Figure 2 A physical photo of a test sample pressing device used in at least one embodiment provided in the present application;

[0037] Figure 3 A photo of a steel cup used in at least one embodiment of the present application;

[0038] Figure 4 A real photo of a steel cup used in at least one embodiment provided in the present application when it is inverted;

[0039] Figure 5 A standard curve diagram of the Fe element content in the standard sample obtained in Example 1 provided in this application;

[0040] Figure 6 This is a standard curve chart of the P element content in the standard sample obtained in Example 1 provided in this application. DETAILED DESCRIPTION

[0041] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments, but the present invention is not limited in any way. Any changes or improvements made based on the teachings of the present invention fall within the protection scope of the present invention.

[0042] Example

[0043] Unless otherwise specified, the materials and instruments used in the following examples were obtained from commercial channels; the detection methods used were all existing methods unless otherwise specified.

[0044] Example 1

[0045] S1: Prepare standard iron phosphate samples and draw standard curves of phosphorus and iron content of standard iron phosphate samples: Prepare 6 standard iron phosphate samples to ensure that the requirements for subsequent testing are met. Different people in the same laboratory test each sample 3 times in succession to obtain the average value: the content range of Fe in the selected standard sample is 36.10-36.50%, and the content range of P is 20.5-21.00%; if the difference between samples is large, the curve can be established in sections;

[0046] 1. Determination of standard samples:

[0047] 1) Fe standard sample determination: Weigh 3.0000g of the iron phosphate standard sample to an accuracy of 0.0002g. Place in a 250ml beaker, moisten with a small amount of water, add 25mL of hydrochloric acid, cover with a watch glass, and let stand in a fume hood to dissolve. Rinse the watch glass with a small amount of water, filter with slow filter paper after cooling, wash the filter residue with water 5 to 7 times, transfer the filtrate to a 250mL volumetric flask, dilute to the scale, and shake well to obtain test solution A.

[0048] Use a pipette to transfer 15 ml of test solution A into a 250 ml conical flask, add 5 ml of hydrochloric acid, and heat to near boiling. While hot, add stannous chloride solution dropwise while shaking the conical flask until the color of the solution changes from brown to light yellow (if the solution becomes colorless after adding too much stannous chloride, add hydrogen peroxide dropwise until the solution turns light yellow).

[0049] Add 4-5 drops of sodium tungstate indicator solution, and add titanium trichloride solution drop by drop while shaking until the solution turns light blue. Immediately cool with running water, add 50mL of water, and titrate the test solution and blank solution with potassium dichromate standard until the blue color just fades (usually 1-2 drops, do not record the reading). Dilute to 100mL with water, add 10mL of sulfuric acid-phosphoric acid mixed solution, 3-4 drops of sodium diphenylamine sulfonate indicator solution, and titrate the solution with potassium dichromate standard until a stable purple-red color (does not disappear in 30 seconds) is the end point.

[0050] The above process was repeated using distilled water instead of the test solution to obtain blank sample data.

[0051] 2) P standard sample determination: Pipette 5.00 mL of experimental solution A into a 500 mL beaker, add 10 mL of nitric acid, dilute with water to 100 mL, cover with a watch glass, heat to a slight boil, add 40 mL of quinoline molybdate reagent with a measuring cylinder while stirring continuously, keep warm on a low-temperature electric hot plate for 5 minutes, remove after the yellow precipitate settles and layers, and let stand to cool to room temperature.

[0052] Use a glass crucible that has been dried to constant weight to filter the supernatant first, then wash the precipitate with 25 mL of water, and carefully transfer the supernatant along the glass rod into the glass crucible by pouring. Repeat this 3 to 4 times, transfer all the precipitate to the crucible, and then wash the precipitate with water 5 to 6 times.

[0053] Place the glass sand core crucible together with the precipitate in an oven at 180°C, dry to constant weight (1h-2h), place in a desiccator to cool for 30min, and weigh the mass of the quinoline phosphomolybdic acid precipitate and the crucible.

[0054] The above process was repeated using distilled water instead of the test solution to obtain blank sample data.

[0055] 2. Calculate the standard sample results

[0056] 1) Iron content is measured by the mass fraction of iron, the value is expressed in %, and is calculated as follows:

[0057]

[0058] Where:

[0059] c—actual concentration of potassium dichromate standard titration solution, in moles per liter (mol / L);

[0060] V—the volume of potassium dichromate standard solution consumed by titrating the sample solution, in milliliters (mL);

[0061] V 1 —The volume of potassium dichromate standard solution consumed in titrating the blank solution, in milliliters (mL);

[0062] V2 —The total volume of the sample solution used, in milliliters (mL);

[0063] M—molar mass of iron in grams per mole (g / mol)

[0064] [M(Fe)=55.85 g / mol];

[0065] m—mass of the sample, in grams (g).

[0066] The result is expressed to two decimal places.

[0067] 2) Phosphorus content is measured as the mass fraction of phosphorus, and the value is expressed in %, calculated as follows:

[0068]

[0069] Where:

[0070] m 1 ——The mass of the quinoline phosphomolybdate precipitate and the crucible, in grams (g);

[0071] m 2 ——The mass of the crucible before filtration, in grams (g);

[0072] m 3 ——The mass of blank test precipitate and crucible, in grams (g);

[0073] m 4 ——The mass of the blank test crucible, in grams (g);

[0074] V 0 ——The total volume of experimental solution A, in milliliters (mL);

[0075] V——volume of the test solution taken, in milliliters (mL);

[0076] m——the mass of the test material used to prepare the test solution, in grams (g);

[0077] 0.0140—Conversion factor of quinoline phosphomolybdate to phosphorus;

[0078] S2: Load and press the sample to be tested: select a stainless steel sample cup with a volume of 30ml and an automatic sample press with a pressure of 50-250kg; take 2.50±0.01g of the sample to be tested and fill it evenly in the stainless steel sample cup and shake it compactly;

[0079] See also Figures 2 to 4The steel cup used includes: an inner core, a cup body, and a plastic sleeve; the interior of the cup body is connected; the sample film is laid on the bottom of the cup body, and the periphery of the sample film is covered by a plastic sleeve and pressed on the outer wall of the bottom of the cup body, thereby fixing the sample film; when in use, after the sample film is sleeved on the bottom of the cup body as a polyester Mylar film, the plastic sleeve is sleeved to press the periphery of the sample film, and the sample film is laid flat on the bottom surface of the cup body; after the sample to be tested is filled in the cup body, one end of the inner core is inserted into the cup body, and the top of the inner core extends out of the cup body and abuts against the lower pressure head of the press. At the same time, the sample film abuts against the mounting table of the press, and the inner core squeezes the sample in the cup downward under the downward push of the lower pressure head of the press. The added volume of the sample to be tested in the cup body is 1 / 10 of the total volume of the cup body. According to this addition, a sample that meets the requirements of subsequent tests can be obtained.

[0080] The press includes: a bracket, a mounting platform, a screw, a pressing head, a mounting platform, a handle, and a base; the bracket is mounted on the base, and the mounting platform is set in the center area of ​​the base; the screw is connected to the center thread of the bracket; a handle is set at the top of the screw; a pressing head is set at the bottom of the screw; the central axis of the screw, the mounting platform, and the base coincides. A handle is set at the top of the bracket where the screw extends out. The handle makes it easy for the operator to control the screw to press down.

[0081] S3: The power of the XRF analysis equipment used: 2.5MPA; the resolution of the detector used is ≤125eV;

[0082] S4: Curve establishment:

[0083] 4.1 Adding curves

[0084] Select "Add Curve" in the instrument curve interface, and add a curve name such as densifier FePO4-CP or a custom name under the curve name, select "FePO4-CP" in the material selection, enter the correction curve name with the same name as the curve in "Add Correction Center", and when entering the required elements, select Fe and P elements.

[0085] 4.2 Curve parameter update

[0086] Move the mouse to the operation interface, click the "whiteboard" on the keyboard, select "Accessoriees", select "FileManager", select "gitee", select "Allcurves", copy the existing solid parameters and paste them to the new curve, then check Apply...., select "Overwrite" to complete the curve parameter update.

[0087] 4.3 Initial analysis of quality control samples

[0088] Select "Settings" in the XRF instrument measurement, select the established new curve (such as FePO4-CP) parameters in the curve, and select the calibration to test two sets of data in the "Defaulf" state.

[0089] 4.4 Initial calibration setting and calibration of curves

[0090] In the "Defaulf" state of the new curve in the "Curve" mode of the instrument, select "Set", check the analysis quality control sample number in the Fe P box, click "Add", enter the sample test results analyzed by multiple people in the same laboratory and converted into ppm in the Fe and P boxes, and enter "0" for "Correction Si", "Original Si" and "CR-K". After confirmation, complete the curve correction setting and calibrate.

[0091] 4.5 Analysis of curve quality control samples and standard samples

[0092] Select "Settings" in the instrument measurement, select Analyze 2 times under the newly created curve such as "FePO4-CP" and calibration "Defaulf", and measure the Y-axis results of the required curve standard sample.

[0093] 4.6 Standard curve drawing

[0094] Select the scatter plot in the table to make a standard curve, and calculate the a and b values ​​of the linear regression of the curve according to the instrument analysis results. Select "Manually set calibration parameters" in the "Open" of the current curve, enter the "a value and b×10000 (ppm) value, and complete the setting of the standard curve after confirmation.

[0095] The test results of the standard samples used in this embodiment are shown in the following table:

[0096] Table 1:

[0097]

[0098] Table 2:

[0099]

[0100] The manual analysis method in Tables 1 and 2 is the titration method described above to determine the content of Fe and P elements in ferric phosphate.

[0101] According to the titration results of each standard sample, the iron and phosphorus contents in the ferric phosphate standard sample are plotted. The horizontal axis of the obtained standard curve is the iron and phosphorus content values ​​of each standard sample obtained by the above titration method; the vertical axis of the obtained standard curve is the iron and phosphorus content values ​​of each standard sample measured by the XRF analyzer according to the steps disclosed in 4.3 to 4.5; the obtained standard curve is as follows: Figures 5-6 shown.

[0102] S5: Curve correction: Curve correction for the day: Select the required curve in "Test" and complete the interface switching in the "Defaulf" state. Select "Set" in "Curve" and confirm to complete the curve correction for the day.

[0103] S6: Quality control sample analysis and data compensation:

[0104] 6.1 Standard sample analysis: Select 2 quality control samples (standard samples) on the required curve such as

[0105] In the "Calibration" box of the test interface, select the same name as the curve (FePO4-CP), set the number of tests in the analysis sample box and select the automatic analysis mode for standard sample detection and analysis.

[0106] 6.2 Data compensation calculation: Compare the test value of the standard sample 6.1 on the day with the standard sample (three consecutive test results by different people in the same laboratory), and calculate the value that needs to be compensated on the day.

[0107] S7: Sample analysis: Select an iron phosphate sample with the same matrix as the standard sample for analysis, and test a parallel sample;

[0108] 7.1 Add film to sample cup: Cover the small diameter side of the stainless steel sample cup with film, fix it with a stainless steel ring, and ensure that the film is flat and wrinkle-free;

[0109] 7.2 Add sample: Return the electronic balance to zero, add 2.5±0.01g of material into the stainless steel sample cup with a stainless steel spoon, gently shake the material in the sample cup to make it flat and loose, and gently rotate the stainless steel inner core with vaseline lubricant downward;

[0110] 7.3 Sample pressing: Adjust the pressure of the sample pressing machine to 2.5mPA for sample pressing. After the sample pressing is completed, wait for 30 seconds before removing the sample and set it aside.

[0111] S8: Sample test: Select the sample prepared in 7.3 in the required curve, select the same name as the curve in the calibration box of the test interface, set the number of tests in the analysis sample box and select the automatic analysis mode to detect and analyze the sample to be tested, and perform at least 2 tests.

[0112] S9: Result calculation: Based on the average of the two tests of the parallel samples in S8 and adding or subtracting the compensation value of the standard sample on the day (quality control sample), calculate the result of the sample tested on the day. The result of the sample tested on the day = the manual test result of the standard sample ± the XRF test result of the standard sample on the day.

[0113] Comparative Example 1:

[0114] The difference from Example 1 is that after the cake is pressed by the conventional boric acid cake pressing method, an XRF instrument is used for testing. The method is described in detail and is operated according to the conventional boric acid cake pressing method.

[0115] The source of the tested samples is: 2.5g of finished iron phosphate product was collected for testing at 9 am on January 20, 2025.

[0116] The same sample was tested using the methods disclosed in Example 1 and Comparative Example 1, and the results are shown in the following table:

[0117] Fe(%) P(％) Example 1 36.320 20.980 Comparative Example 1 36.321 20.991

[0118] As can be seen from the above table, the measurement results obtained by the method provided in the present application are similar to the results obtained by the existing traditional boric acid cake pressing method, with little difference, and can meet the detection needs in the existing industrial large-scale production process.

[0119] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An XRF detection method for analyzing phosphorus content in iron phosphate analysis, characterized in that: The following steps are involved: Step S1: preparing a standard ferric phosphate sample, titrating the iron and phosphorus contents in the obtained standard ferric phosphate sample, and using the obtained contents as the abscissa value of the phosphorus and iron content standard curve of the standard ferric phosphate sample; the Fe content in the standard ferric phosphate sample used is in the range of 36.10-36.50%, and the P content is in the range of 20.5-21.00%; Step S2: After a sample-preparing film is sleeved on the bottom of the cup body of the steel cup, a plastic sleeve ring is sleeved to press the periphery of the sample-preparing film, and the sample-preparing film is laid flat on the bottom surface of the cup body, and the sample to be tested is filled with 1 / 10 of the total volume of the cup body and then pressed; the sample to be tested is the product to be tested or a standard iron phosphate sample; Step S3: Select an XRF analyzer with a power of 2.5 MPA and a detector resolution of ≤125 eV for setting, perform quality control sample analysis and data compensation after curve calibration, perform sample analysis on the pressure sample to be tested, and obtain the XRF test result. The XRF test result of the standard iron phosphate sample is used as the ordinate value of the standard curve of the phosphorus and iron contents of the standard iron phosphate sample, and the standard curves of the phosphorus and iron contents of the standard iron phosphate sample are drawn respectively; Step S4: The average of the two tests of the parallel sample is added and subtracted from the compensation value of the standard sample on the day (quality control sample), and the result of the test sample on the day is calculated. The result of the test sample on the day = the manual test result of the standard sample ± the XRF test result of the standard sample on the day. The manual test result is the phosphorus and iron content in the sample determined by titration.

2. The XRF detection method for phosphorus content analysis in iron phosphate analysis according to claim 1, characterized in that: The preparation of the pressure sample to be tested in step S2 includes the following steps: Step S21: selecting an iron phosphate sample having the same matrix as the standard sample for analysis, and testing a parallel sample; Step S22: Cover the side of the stainless steel sample cup with a smaller diameter with a sample preparation film, fix it with a plastic ring, and ensure that the sample preparation film is flat and wrinkle-free; Step S23: Return the electronic balance to zero, add 2.5±0.01 g of material into the stainless steel sample cup with a stainless steel spoon, gently shake the material in the sample cup to make it flat and loose, and gently rotate the stainless steel inner core with vaseline lubricant downward; Step S24: Adjust the pressure of the sample pressing machine to 2.5 mPA to perform the sample pressing operation. After the sample pressing is completed, wait for 30 seconds to remove the sample to obtain the sample to be tested.

3. The XRF detection method for phosphorus content analysis in iron phosphate analysis according to claim 1, characterized in that: The "setting" in step S3 includes the following steps: Step S311: Before measuring, select "Add curve" and add a curve name under Curve name, select "FePO4-CP" in Material selection, enter the calibration curve name with the same name as the curve in "Add calibration center", and select Fe and P elements when entering the required elements; Step S312: Click the keyboard "whiteboard", select "Accessoriees", select "File Manager", select "gitee", select "Allcurves", copy the existing solid parameters and paste them to the new curve, then check Apply...., select "Overwrite" to complete the curve parameter update; Step S313: Select "Settings" in the XRF instrument measurement, select the established new curve "FePO4-CP" parameters in the curve, and select the calibration to test two sets of data in the "Defaulf" state; Step S314: In the "Defaulf" state of the new curve in the "Curve" mode of the instrument, select "Set", check the analysis quality control sample number in the Fe P box, click "Add", enter the sample test results analyzed by multiple people in the same laboratory and converted into ppm in the Fe and P boxes, and enter "0" for "Correction Si", "Original Si", and "CR-K". After confirmation, complete the curve calibration setting and calibrate; Step S315: Select "Settings" in the instrument measurement, select Analyze 2 times under the newly created curve such as "FePO4-CP" and calibration "Defaulf", and measure the Y-axis result of the required curve standard sample. Step S316: Select the scatter plot in the table to make a standard curve, and calculate the a and b values ​​of the linear regression of the curve according to the instrument analysis results. Select "Manually set calibration parameters" in the current curve "Open" to enter the a value and b×10000 (ppm) value, and complete the setting of the standard curve after confirmation.

4. The XRF detection method for phosphorus content analysis in iron phosphate analysis according to claim 1, characterized in that: The "curve correction" in step S3 includes the following steps: Curve correction for the day: select the required curve in "Test" and complete the interface switching in the "Defaulf" state, select "Set" in "Curve" and confirm the completion of the curve correction for the day.

5. The XRF detection method for phosphorus content analysis in iron phosphate analysis according to claim 1, characterized in that: The "quality control sample analysis and data compensation" in step S3 includes the following steps: Step S321: Select 2 quality control samples (standard samples) in the required curve such as (FePO4-CP) and select the same name as the curve in the "Calibration" box of the test interface, such as (FePO4-CP), set the number of tests in the analysis sample box and select the automatic analysis mode to perform standard sample detection and analysis; Step S321: Compare the test value of the day in step S321 with the standard sample (three consecutive test results by different people in the same laboratory), and calculate the value that needs to be compensated on the day.

6. The XRF detection method for phosphorus content analysis in iron phosphate analysis according to claim 2, characterized in that: The pressing machine includes: a bracket, a mounting platform, a screw, a pressing head, a mounting platform, a handle, and a base; the bracket is installed on the base, and the mounting platform is arranged in the central area of ​​the base; the screw is connected to the center thread of the bracket; a handle is arranged at the top of the screw; a pressing head is arranged at the bottom of the screw; the central axis of the screw, the mounting platform, and the base coincides.

7. The XRF detection method for phosphorus content analysis in iron phosphate analysis according to claim 2, characterized in that: The stainless steel cup comprises: an inner core, a cup body, and a plastic sleeve ring; the interior of the cup body is connected; a sample-making film is laid on the bottom of the cup body, and the periphery of the sample-making film is covered by the plastic sleeve ring and pressed on the outer wall of the bottom of the cup body; After the sample to be tested is filled in the cup body, one end of the inner core is inserted into the cup body, and the top of the inner core is extended out of the cup body and abuts against the lower pressing head of the sample pressing machine.

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