Preparation and use method of standard sample for X-ray fluorescence analysis

Abstract

The invention discloses a preparation and use method of a standard sample for X-ray fluorescence analysis, and relates to the field of testing. The preparation method of the standard sample for X-ray fluorescence analysis comprises the following steps: mixing standard reagents of various to-be-detected elements with a release agent and a flux, and shaking and uniformly mixing to obtain a mixed sample; pouring the uniformly stirred sample into a mold, compacting and cutting into a plurality of sample blocks; according to the preparation method and the use method of the standard sample for X-ray fluorescence analysis, a standard sample group which meets the X-ray analysis requirement and is wide in content distribution range and good in step shape can be prepared, the workload of manually preparing the standard sample is greatly reduced, the accuracy and the efficiency of sample preparation are improved, and the method is suitable for large-scale popularization and application. The technical problems that the number of standard samples for X-ray fluorescence is small, and preparation is not easy are solved.

Description

Technical Field

[0001] The present application relates to the field of testing, and in particular to a method for preparing and using a standard sample for X-ray fluorescence analysis. Background Art

[0002] The establishment of the standard curve of X-ray fluorescence spectrometry requires a large number of standard samples, and there are certain requirements for the types and content ranges of the elements to be measured. If the number of standard samples is insufficient, there is no standard sample group with a wide content distribution range and a good step shape, or there are no standard samples that meet the requirements for sale, standard samples need to be prepared manually.

[0003] The usual method of preparing standard samples is to weigh the reference reagents of the elements to be measured in turn according to the required ratio, mix them evenly, and use them as a standard sample for establishing a standard curve. The number of standard samples of the corresponding ratio is the number of points required to establish the standard curve. The disadvantage of this method is that it is labor-intensive. Each reference reagent of the element to be measured needs to be accurately weighed. If there are many elements to be measured, a large number of standard samples need to be prepared, which is a very large workload. In addition, the content of some elements to be measured is very low, so the amount of reference reagent weighed will be very small, as low as a dozen milligrams or even a few milligrams, which puts very high demands on the weighing equipment, environment, and personnel. Summary of the invention

[0004] The purpose of the present application is to provide a method for preparing and using standard samples for X-ray fluorescence analysis, which can prepare a standard sample group with a wide content distribution range and good step shape that meets the requirements of X-ray analysis, greatly reducing the workload of manually preparing standard samples, improving the accuracy and efficiency of sample configuration, and solving the technical problems of few standard samples for X-ray fluorescence and difficult preparation.

[0005] This application is implemented as follows:

[0006] The present application provides a method for preparing a standard sample for X-ray fluorescence analysis, comprising the following steps:

[0007] Mixing the reference reagents of multiple elements to be tested with the release agent and the flux, and then shaking and mixing to obtain a mixed sample;

[0008] The evenly mixed sample is poured into a mold, compacted and cut into multiple specimens.

[0009] In some optional embodiments, the reference reagents for the various elements to be tested include SiO2, Fe2O3, Al2O3, CaCO3, MgO, TiO2, MnO2, Cr2O3, ZrO2, LiPO3, Li2SO4, K2CO3, Na2CO3, WO3, V2O5, and LiF.

[0010] In some optional embodiments, the mass ratio of the reference reagent, the release agent, and the flux of the element to be measured is 1-0.5:0.033-0.083:10.

[0011] In some optional embodiments, the release agent includes NH4Br, NH4I.

[0012] In some optional embodiments, the flux is fired at above 700° C. for more than 9 hours before being mixed.

[0013] In some optional embodiments, when pouring the uniformly stirred sample into a mold for compaction, the pressure is maintained at 20-40t for 20-30s.

[0014] In some optional embodiments, when the uniformly stirred sample is poured into a mold, compacted and cut into a plurality of sample blocks, the number of the sample blocks cut is the same as the gram weight of the flux.

[0015] In some optional embodiments, the following steps are also included: the cut samples are sealed using PTP blister packaging, the PTP blister includes a blister made of polyvinyl chloride or polyvinylidene chloride and a covering layer covering the outer wall of the blister, and the covering layer is aluminum foil or an aluminum foil composite material.

[0016] In some optional embodiments, the reference reagent of the element to be detected is dried or incinerated before mixing.

[0017] The present application also provides a method for using a standard sample for X-ray fluorescence analysis, which comprises the following steps:

[0018] Using the above-mentioned standard sample preparation method for X-ray fluorescence analysis, multiple groups of samples are prepared, each group of samples contains different contents of the elements to be tested;

[0019] Selectively mixing and melting a plurality of sample blocks to prepare a standard sample glass sample, wherein the sum of the contents of the elements to be measured in the plurality of sample blocks is equal to the content of the required elements to be measured;

[0020] The standard sample glass coupons were analyzed using an X-ray fluorescence analysis method.

[0021] The beneficial effects of the present application are as follows: the method for preparing standard samples for X-ray fluorescence analysis provided by the present application comprises the following steps: mixing the reference reagents of multiple elements to be tested with a release agent and a flux, and then shaking and mixing to obtain a mixed sample; pouring the stirred sample into a mold, compacting it, and cutting it into multiple sample blocks. The method for preparing standard samples for X-ray fluorescence analysis and the method for using the method provided by the present application can prepare a standard sample group with a wide content distribution range and good step shape that meets the requirements of X-ray analysis, greatly reducing the workload of manually preparing standard samples, improving the accuracy and efficiency of sample configuration, and solving the technical problems of few standard samples for X-ray fluorescence and difficulty in preparation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 A schematic diagram of the structure of a tablet press in the method for preparing a standard sample for X-ray fluorescence analysis provided in an embodiment of the present application;

[0024] Figure 2 This is a schematic diagram of the structure of the sample press cover in the standard sample preparation method for X-ray fluorescence analysis provided in an embodiment of the present application.

[0025] In the figure: 100, tablet press; 110, workbench; 120, swing arm; 130, hydraulic cylinder; 131, pressing head; 140, press cover; 150, blade slot; 160, cutting mechanism; 170, transverse blade; 180, longitudinal blade; 200, mold. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0028] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0029] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the application is usually placed when in use. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0030] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0031] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0032] In the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0033] The characteristics and performance of the standard sample preparation method and use method for X-ray fluorescence analysis of the present application are further described in detail below in conjunction with the examples.

[0034] like Figure 1 and Figure 2 As shown, the present application embodiment provides a method for preparing a standard sample for X-ray fluorescence analysis, comprising the following steps:

[0035] Step 1: Mix the reference reagents of various elements to be tested with the release agent and flux, put them into a white plastic barrel, add zirconium oxide balls, shake and mix them on a mixer for about 36 hours, and stir them evenly to obtain a mixed sample; optionally, the reference reagents of various elements to be tested include SiO2, Fe2O3, Al2O3, CaCO3, MgO, TiO2, MnO2, Cr2O3, ZrO2, LiPO3, Li2SO4, K2CO3, Na2CO3, WO3, V2O5, LiF; optionally, the mass ratio of the reference reagents, release agent, and flux of the elements to be tested is 1-0.5: 0.033-0.083: 10. Optionally, the release agent includes NH4Br and NH4I. Optionally, the flux is calcined at above 700° C. for more than 9 hours before mixing; optionally, the reference reagent of the element to be measured is dried or calcined before mixing; optionally, the flux can be a single type of flux or a mixture of multiple fluxes.

[0036] Step 2: Pour the evenly stirred sample into the mold of the tablet press 100, flatten it with a flattener, cover it with the tablet press cover 140, and use the tablet press 100 to compact and cut it into multiple blocks. Optionally, when pouring the evenly stirred sample into the mold for compaction, maintain the pressure at 20-40t for 20-30s. Optionally, when pouring the evenly stirred sample into the mold for compaction and cutting it into multiple blocks, the number of blocks cut is the same as the grams of the flux. Optionally, when cutting into multiple blocks, control the blade cutter on the top wall of the tablet press cover 140 to descend to cut the compacted sample into blocks of uniform size;

[0037] Step 3: The cut sample is sealed using a PTP blister package. The PTP blister includes a blister made of polyvinyl chloride or polyvinylidene chloride and a covering layer covering the outer wall of the blister. The covering layer is aluminum foil or an aluminum foil composite material.

[0038] The present application also provides a method for using a standard sample for X-ray fluorescence analysis, which comprises the following steps:

[0039] Step 1: prepare multiple groups of samples using the above-mentioned standard sample preparation method for X-ray fluorescence analysis, each group of samples containing different contents of the elements to be tested;

[0040] Step 2: selectively mix and melt multiple sample blocks to prepare standard sample glass samples, and the sum of the contents of the elements to be tested in the multiple sample blocks is equal to the content of the required elements to be tested.

[0041] Step 3: Analyze the standard sample glass sample using an X-ray fluorescence analysis method.

[0042] The method for preparing standard samples for X-ray fluorescence analysis provided by the present application innovatively mixes the reference reagents, co-solvents and fluxes of various elements to be tested in a certain proportion, pours them into a mold for compaction and then cuts them into sample blocks of uniform size. By separately preparing sample blocks with different contents of the elements to be tested, different sample blocks are added according to the required element content gradient to prepare an X-ray fluorescence analysis standard sample group that meets the requirements, has a wide content distribution range and a good step shape. This achieves a new breakthrough in the manual preparation of standard samples for X-ray fluorescence analysis, greatly reduces the workload of manual preparation of standard samples, improves the accuracy and efficiency of the sample preparation process, and solves the technical problems of few standard samples for X-ray fluorescence and difficulty in preparation.

[0043] The tablet press 100 used in the present application includes a workbench 110 for supporting a mold 200, a swing arm 120 connected to the top of the workbench 110, a hydraulic cylinder 130 connected to the swing arm 120, and a pressing head 131 connected to the hydraulic rod of the hydraulic cylinder 130. The hydraulic cylinder 130 is used to drive the pressing head 131 to move up and down to compress the pressing machine cover 140 on the top of the mold 200, so that the pressing machine cover 140 pressed down compacts the sample in the mold 200, wherein the bottom wall of the pressing machine cover 140 is provided with a blade groove 150, and a grid-shaped blade cutter is provided in the blade groove 150 of the pressing machine cover 140. A cutting mechanism 160 for driving the blade cutter to move up and down is provided on the top of the pressing machine cover 140. The cutting mechanism 160 drives the blade cutter to descend and cut the sample in the mold 200. The blade cutter is composed of nine transverse blades 170 arranged transversely and nine longitudinal blades 180 arranged longitudinally, and the cutting mechanism 160 is a cylinder.

[0044] The use of blister packaging technology to package the samples can isolate the samples from each other, reduce or even eliminate sample contamination, and ensure that there will be no collision between the samples even during transportation, so that the samples are well protected. When in use, the aluminum foil can be broken by applying pressure, making it very convenient to take. Due to the performance of the blister packaging material, the samples have good sealing and protection after packaging, extending the storage time of the samples; at the same time, the preparation date, the ratio of the reference reagent, the ratio of the reference reagent to the release agent, the flux and other information are printed on the surface of the aluminum foil, so that the sample information is clear at a glance. Blister packaging can also use a unified packaging to package the samples through the changes in the plate size and the aluminum foil, so as to realize the serialization of sample packaging.

[0045] Example 1

[0046] The embodiment of the present application provides a method for preparing a standard sample for X-ray fluorescence analysis, which is used to prepare an aluminum-silicon standard sample with a silicon dioxide mass percentage content of 30-90%, comprising the following steps:

[0047] Step 1: Pre-treat the reference reagent of the element to be measured, and dry or burn it as required; select a mixed flux of lithium tetraborate and lithium metaborate, the mass ratio of the two fluxes is 67:33, and burn the mixed flux at 700°C for 10 hours; select NH4I as the release agent.

[0048] Step 2: Weigh the sample according to the mass ratio of the reference reagent, release agent and flux of the element to be measured in 1:0.083:10, where the mass of the reference reagent of the element to be measured is 10.0000g, the mass of the release agent NH4I is 0.8300g, and the mass of the mixed flux is 100.0000g. The weighed amount of the reference substance of the element to be measured is shown in Table 1 below.

[0049] Table 1 Sample weight of reference materials for the elements to be measured

[0050] <![CDATA[SiO2]]> <![CDATA[Fe2O3]]> <![CDATA[Al2O3]]> <![CDATA[CaCO3]]> MgO <![CDATA[TiO2]]> <![CDATA[K2CO3]]> <![CDATA[Na2CO3]]> <![CDATA[LiPO3]]> <![CDATA[Cr2O3]]> <![CDATA[ZrO2]]> a 9.0000 0.0100 0.0100 0.1785 0.1000 0.1000 0.2787 0.3249 0.1211 0.1000 0.1000 b 3.0000 0.9200 6.0000 0.0178 0.0100 0.0100 0.0147 0.0171 0.0121 0.0100 0.0100

[0051] Among them, CaCO3 and other reference reagents will decompose into pure oxides when melting the sample. 10.0000g is calculated based on the proportion of pure oxides, but it will still be calculated based on CaCO3 when weighing the sample. Therefore, the total mass of the reference reagents for the elements to be measured in the table is greater than 10g.

[0052] Step 3. Weigh the reference materials to be tested in group a and group b in Table 1, add flux and release agent, pour into a white plastic bucket, add zirconium oxide balls, shake and mix on a mixer for about 36 hours, and stir thoroughly to obtain sample a and sample b.

[0053] Step 4: Pour the evenly stirred sample a and sample b into the mold of the tablet press 100 respectively, flatten them with a flattener and cover them with the tablet press cover 140, start the tablet press 100 and press the samples at a pressure of 40t for 30s to compact them.

[0054] Step 5: Control the blade cutter to descend and cut the pressed sample into blocks of uniform size. The blade cutter is composed of nine transverse blades 170 arranged transversely and nine longitudinal blades 180 arranged longitudinally to form a 10×10 matrix, thereby cutting the sample into 100 blocks of uniform size.

[0055] Step 6: Remove the sample pressing machine cover 140, take out the sample block, seal it in a PTP blister package, and print the preparation date, reference reagent ratio, reference reagent and release agent, flux ratio and other information on its surface.

[0056] Step 7. Test the uniformity and accuracy of the prepared samples. The uniformity and accuracy tests must be carried out under the condition of ensuring the stability of the instrument, consistent experimental conditions, and consistent operating level of the personnel. The uniformity test method specifically includes: randomly selecting 9 samples from the same batch, dividing them into three groups, each with three blocks, adding 3.0000g of mixed flux and 0.0200g of release agent to each group to melt them, and measuring the content of the elements to be measured by X-ray fluorescence, and analyzing each group of samples 5 times at the same time. The range method is used for the statistics of uniformity inspection data, that is, the difference between the maximum and minimum values ​​must be less than the allowable difference specified in the standard GB / T 21114-2019. If the difference between the maximum and minimum values ​​is greater than the allowable difference specified in the standard GB / T 21114-2019 without abnormal values, it is considered that the uniformity is not good and this batch is discarded. The accuracy test method specifically includes: the difference between the average value of the content of the elements to be measured by fluorescence of the above three groups of samples and the theoretical value must be less than the allowable difference specified in the standard GB / T21114-2019. If the difference between the average value and the theoretical value is greater than the allowable difference specified in standard GB / T 21114-2019 in the absence of abnormal values, it is considered to be inaccurate and the batch is discarded.

[0057] Step 8. Mix the samples a and b that have passed the uniformity and accuracy tests according to Table 2 below to obtain a set of aluminum-silicon standard samples with a silicon dioxide content of 30-90%. Use this set of series of standard samples to establish an X-ray fluorescence spectrum working curve. Select a sample, select the same sample preparation conditions as the standard sample, prepare it into a test sample, and use the working curve to automatically calculate the content of each element in the sample.

[0058] Table 2 Content of artificially prepared aluminum silicon series standard samples

[0059]

[0060] Example 2

[0061] The embodiment of the present application provides a method for preparing a standard sample for X-ray fluorescence analysis, which is used to prepare an aluminum-magnesium standard sample with a magnesium oxide mass percentage content of 15-90%, comprising the following steps:

[0062] Step 1: Pre-treat the reference reagent of the element to be measured, and dry or burn it as required; select a mixed flux of lithium tetraborate and lithium metaborate, the mass ratio of the two fluxes is 67:33, and burn the mixed flux at 700°C for 10 hours; select NH4I as the release agent.

[0063] Step 2: Weigh the sample according to the mass ratio of the reference reagent, release agent and flux of the element to be measured in 1:0.083:10, where the mass of the reference reagent of the element to be measured is 10.0000g, the mass of the release agent NH4I is 0.8300g, and the mass of the mixed flux is 100.0000g. The weighed amount of the reference substance of the element to be measured is shown in Table 1 below.

[0064] Table 3 Sample weight of reference materials for the elements to be measured

[0065] <![CDATA[SiO2]]> <![CDATA[Fe2O3]]> <![CDATA[Al2O3]]> <![CDATA[CaCO3]]> MgO <![CDATA[TiO2]]> <![CDATA[K2CO3]]> <![CDATA[Na2CO3]]> <![CDATA[LiPO3]]> <![CDATA[Cr2O3]]> <![CDATA[ZrO2]]> c 3.0000 0.9200 6.0000 0.0178 0.0100 0.0100 0.0147 0.0171 0.0121 0.0100 0.0100 d 0.0000 0.0000 0.0000 0.7140 9.0000 0.1000 0.1467 0.1710 0.1211 0.1000 0.1000

[0066] Among them, CaCO3 and other reference reagents will decompose into pure oxides when melting the sample. 10.0000g is calculated based on the proportion of pure oxides, but it will still be calculated based on CaCO3 when weighing the sample. Therefore, the total mass of the reference reagents for the elements to be measured in the table is greater than 10g.

[0067] Step 3. Weigh the reference materials to be tested in group c and group d in Table 3, add flux and release agent respectively, pour into a white plastic bucket, add zirconium oxide balls, shake and mix on a mixer for about 36 hours, and stir thoroughly to obtain sample c and sample d.

[0068] Step 4: Pour the evenly stirred sample c and sample d into the mold of the tablet press 100 respectively, flatten them with a flattener and cover them with the tablet press cover 140, start the tablet press 100 and press the samples at a pressure of 40t for 30s to compact them.

[0069] Step 5: Control the blade cutter to descend and cut the pressed sample into blocks of uniform size. The blade cutter is composed of nine transverse blades 170 arranged transversely and nine longitudinal blades 180 arranged longitudinally to form a 10×10 matrix, thereby cutting the sample into 100 blocks of uniform size.

[0070] Step 6: Remove the sample pressing machine cover 140, take out the sample block, seal it in a PTP blister package, and print the preparation date, reference reagent ratio, reference reagent and release agent, flux ratio and other information on its surface.

[0071] Step 7. Test the uniformity and accuracy of the prepared samples. The uniformity and accuracy tests must be carried out under the condition of ensuring the stability of the instrument, consistent experimental conditions, and consistent operating level of the personnel. The uniformity test method specifically includes: randomly selecting 9 samples from the same batch, dividing them into three groups, each with three blocks, adding 3.0000g of mixed flux and 0.0200g of release agent to each group to melt them, and measuring the content of the elements to be measured by X-ray fluorescence. Each group of samples is analyzed 5 times at the same time, and the uniformity inspection data statistics adopt the range method, that is, the difference between the maximum and minimum values ​​must be less than the allowable difference specified in the standard GB / T 21114-2019. If the difference between the maximum and minimum values ​​is greater than the allowable difference specified in the standard GB / T 21114-2019 in the absence of abnormal values, it is considered that the uniformity is not good and this batch is discarded. The accuracy test method specifically includes: the difference between the average value of the content of the elements to be measured by fluorescence measurement of the above three groups of samples and the theoretical value must be less than the allowable difference specified in the standard GB / T21114-2019. If the difference between the average value and the theoretical value is greater than the allowable difference specified in standard GB / T 21114-2019 in the absence of abnormal values, it is considered to be inaccurate and the batch is discarded.

[0072] Step 8. Mix the samples that have passed the uniformity and accuracy tests with sample c and sample d according to Table 4 below to obtain a set of aluminum-magnesium standard samples with a magnesium oxide content of 15-90%. Use this set of series of standard samples to establish an X-ray fluorescence spectrum working curve. Select a sample, select the same sample preparation conditions as the standard sample, prepare it into a test sample, and use the working curve to automatically calculate the content of each element in the sample.

[0073] Table 4 Content of artificially prepared aluminum-magnesium series standard samples

[0074]

[0075]

[0076] Example 3

[0077] The embodiment of the present application provides a method for preparing a standard sample for X-ray fluorescence analysis, which is used to prepare a magnesium-chromium standard sample with a chromium trioxide mass percentage content of 6-55%, comprising the following steps:

[0078] Step 1: Pre-treat the reference reagent of the element to be measured, and dry or burn it as required; select a mixed flux of lithium tetraborate and lithium metaborate, the mass ratio of the two fluxes is 67:33, and burn the mixed flux at 700°C for 10 hours; select NH4I as the release agent.

[0079] Step 2: Weigh the sample according to the mass ratio of the reference reagent, release agent and flux of the element to be measured in 1:0.083:10, where the mass of the reference reagent of the element to be measured is 10.0000g, the mass of the release agent NH4I is 0.8300g, and the mass of the mixed flux is 100.0000g. The weighed mass of the reference substance of the element to be measured is shown in Table 5 below.

[0080] Table 5 Sample weight of reference substances for the elements to be measured

[0081]

[0082] Among them, CaCO3 and other reference reagents will decompose into pure oxides when melting the sample. 10.0000g is calculated based on the proportion of pure oxides, but it will still be calculated based on CaCO3 when weighing the sample. Therefore, the total mass of the reference reagents for the elements to be measured in the table is greater than 10g.

[0083] Step 3. Weigh the reference materials to be tested in group e and group f in Table 5, add flux and release agent respectively, pour into a white plastic bucket, add zirconium oxide balls, shake and mix on a mixer for about 36 hours, and stir thoroughly to obtain samples e and f.

[0084] Step 4: Pour the evenly stirred samples e and f into the molds of the tablet press 100 respectively, flatten them with a flattener and cover them with the tablet press cover 140, start the tablet press 100 and press the samples at a pressure of 40t for 30s to compact them.

[0085] Step 5: Control the blade cutter to descend and cut the pressed sample into blocks of uniform size. The blade cutter is composed of nine transverse blades 170 arranged transversely and nine longitudinal blades 180 arranged longitudinally to form a 10×10 matrix, thereby cutting the sample into 100 blocks of uniform size.

[0086] Step 6: Remove the sample pressing machine cover 140, take out the sample block, seal it in a PTP blister package, and print the preparation date, reference reagent ratio, reference reagent and release agent, flux ratio and other information on its surface.

[0087] Step 7. Test the uniformity and accuracy of the prepared samples. The uniformity and accuracy tests must be carried out under the condition of ensuring the stability of the instrument, consistent experimental conditions, and consistent operating level of the personnel. The uniformity test method specifically includes: randomly selecting 9 samples from the same batch, dividing them into three groups, each with three blocks, adding 3.0000g of mixed flux and 0.0200g of release agent to each group to melt them, and measuring the content of the elements to be measured by X-ray fluorescence, and analyzing each group of samples 5 times at the same time. The range method is used for the statistics of uniformity inspection data, that is, the difference between the maximum and minimum values ​​must be less than the allowable difference specified in the standard GB / T 21114-2019. If the difference between the maximum and minimum values ​​is greater than the allowable difference specified in the standard GB / T 21114-2019 without abnormal values, it is considered that the uniformity is not good and this batch is discarded. The accuracy test method specifically includes: the difference between the average value of the content of the elements to be measured by fluorescence of the above three groups of samples and the theoretical value must be less than the allowable difference specified in the standard GB / T21114-2019. If the difference between the average value and the theoretical value is greater than the allowable difference specified in standard GB / T 21114-2019 in the absence of abnormal values, it is considered to be inaccurate and the batch is discarded.

[0088] Step 8. Mix the samples that have passed the uniformity and accuracy tests with the sample e and sample f according to Table 6 below to obtain a set of magnesium-chromium standard samples with a chromium trioxide content of 6-55%. Use this set of series of standard samples to establish an X-ray fluorescence spectrum working curve. Select a sample, select the same sample preparation conditions as the standard sample, prepare it into a test sample, and use the working curve to automatically calculate the content of each element in the sample.

[0089] Table 6 Content of standard samples of artificially prepared magnesium-chromium series

[0090]

[0091] The embodiments described above are part of the embodiments of the present application, rather than all of the embodiments. The detailed description of the embodiments of the present application is not intended to limit the scope of the present application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

Claims

1. A method for preparing a standard sample for X-ray fluorescence analysis, characterized in that: The following steps are involved: Mixing the reference reagents of multiple elements to be tested with a release agent and a flux, and then shaking and mixing to obtain a mixed sample; The evenly mixed sample is poured into a mold, compacted and cut into multiple specimens.

2. The method for preparing a standard sample for X-ray fluorescence analysis according to claim 1, characterized in that: The reference reagents for the various elements to be tested include SiO2, Fe2O3, Al2O3, CaCO3, MgO, TiO2, MnO2, Cr2O3, ZrO2, LiPO3, Li2SO4, K2CO3, Na2CO3, WO3, V2O5, and LiF.

3. The method for preparing a standard sample for X-ray fluorescence analysis according to claim 1, characterized in that: The mass ratio of the reference reagent of the element to be measured, the release agent and the flux is 1-0.5:0.033-0.083:

10.

4. The method for preparing a standard sample for X-ray fluorescence analysis according to claim 1, characterized in that: The release agent includes NH4Br and NH4I.

5. The method for preparing a standard sample for X-ray fluorescence analysis according to claim 1, characterized in that: The flux is burned at above 700° C. for more than 9 hours before mixing.

6. The method for preparing a standard sample for X-ray fluorescence analysis according to claim 1, characterized in that: When pouring the evenly stirred sample into the mold and compacting it, maintain the pressure at 20-40t for 20-30s.

7. The method for preparing a standard sample for X-ray fluorescence analysis according to claim 1, characterized in that: When the evenly stirred sample is poured into a mold, compacted and cut into a plurality of sample blocks, the number of the sample blocks cut is the same as the gram weight of the flux.

8. The method for preparing a standard sample for X-ray fluorescence analysis according to claim 1, characterized in that: The following steps are also included: The cut sample blocks are sealed in a PTP blister package, wherein the PTP blister comprises a blister made of polyvinyl chloride or polyvinylidene chloride and a covering layer covering the outer wall of the blister, wherein the covering layer is aluminum foil or an aluminum foil composite material.

9. The method for preparing a standard sample for X-ray fluorescence analysis according to claim 1, characterized in that: The reference material of the element to be measured is dried or burned before mixing.

10. A method for using a standard sample for X-ray fluorescence analysis, characterized in that: It includes the following steps: Using the standard sample preparation method for X-ray fluorescence analysis according to any one of claims 1 to 9 to prepare multiple groups of sample blocks, each group of sample blocks contains different contents of the element to be tested; Selectively mixing and melting a plurality of the sample blocks to prepare a standard sample glass sample, wherein the sum of the contents of the elements to be measured in the plurality of the sample blocks is equal to the content of the required elements to be measured; The standard sample glass coupons were analyzed using an X-ray fluorescence analysis method.

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