Construction and component detection method of mirabilite XRF (X-Ray Fluorescence) detection standard working curve

Abstract

The invention relates to a mirabilite XRF detection standard working curve construction and component detection method. The method comprises the following steps: preparation of a standard sample, preparation of a standard detection product, drawing of a standard working curve, and detection, analysis and calculation. A sample is pre-melted for 20 minutes at the temperature of 450-500 DEG C before XRF detection, then is melted for 15-25 minutes at the temperature of 900-1050 DEG C, and is naturally cooled. Different from the prior art, according to the technical scheme, the sample is subjected to melting treatment, the mineral effect is eliminated, the particle size effect is overcome, and the measurement error is reduced; the preparation method comprises the following steps: adding lithium nitrate, anhydrous lithium tetraborate and lithium metaborate fluxing agents before melting, pre-melting at 450-500 DEG C for 20 minutes, and enabling the lithium nitrate, the lithium tetraborate and the lithium metaborate to act synergistically to fix the sulfur element in the anhydrous sodium sulfate and prevent the sulfur element from volatilizing, so that the accuracy of a detection result is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the detection method in the field of glass manufacturing, and particularly relates to a construction method of a mirabilite XRF detection standard working curve and a component detection method. BACKGROUND

[0002] Mirabilite is one of important raw materials in glass manufacturing, which mainly acts as a fluxing agent to help reduce the melting temperature of glass, improve the transparency and gloss of glass, and affect other properties of glass. In the glass production process, reasonable use and control of mirabilite is the key to ensure the quality of glass. The main component of mirabilite is Na2SO4, and it also contains impurities NaCl and Fe2O3. Therefore, rapid and accurate determination of the main chemical components and their contents in mirabilite has certain guiding significance for the production of float glass.

[0003] The traditional determination method of mirabilite, chemical titration method and gravimetric method, has the disadvantages of complicated process, long time consumption, sample destruction, and high requirement for the operation level of the analyst.

[0004] At present, the mirabilite XRF detection mainly adopts the tablet method for detection. Since the intensity of the fluorescence spectrometer changes during use, it is necessary to regularly use standard samples to correct the standard curve. However, mirabilite is easy to absorb water, and the standard sample is prone to moisture and difficult to store, resulting in deviation in the standard curve correction process. The tablet method for determining the components of mirabilite uses high-purity reagents as standard samples for the establishment of the powder method standard curve of mirabilite, which can only determine the main components of mirabilite, and cannot directly analyze and determine the impurities NaCl and Fe2O3. Moreover, the establishment of the detection method by the tablet method has high requirements for the uniformity, flatness and force of the standard sample, otherwise it will affect the accuracy of the results. SUMMARY

[0005] In view of the above problems, the present application provides a construction method of a mirabilite XRF detection standard working curve and a component detection method. The sample treatment of the test method is simple, and the accurate contents of the main component Na2SO4 and the impurity components NaCl and Fe2O3 in mirabilite can be accurately determined, which is a high-efficiency and high-reliability X-ray fluorescence spectrometry method. At the same time, since the present application uses the fusion tablet method to treat the sample to be tested, the fusion tablet reduces the matrix effect and particle size effect through high-temperature melting, greatly improving the accuracy of the analysis results.

[0006] The first aspect of the present application discloses a construction method of a mirabilite XRF detection standard working curve, comprising the following steps:

[0007] Preparation of standard samples: gradient mixing of anhydrous sodium sulfate, sodium chloride and iron oxide according to predetermined contents to obtain three or more standard samples;

[0008] Preparation of standard test products: After uniformly mixing the standard sample with flux and lithium nitrate, pre-melt at 450-500℃ for 20 minutes, then melt at 900-1050℃ for 15-25 minutes, and cool naturally to obtain the standard test product;

[0009] Drawing of standard working curve: Place the standard test sample into the X-ray fluorescence spectrometer, detect the Kcps values ​​of S, Cl, and Fe elements respectively, and draw the standard working curve of Glauber's salt XRF detection corresponding to the content of sodium sulfate, sodium chloride, and iron oxide.

[0010] Lithium nitrate is completely melted at 253℃ and begins to decompose slowly at 450℃, generating Li2O, NO2 and O2, releasing sulfur-fixing active species. It will decompose violently above 500℃, resulting in sample splashing and loss, and incomplete reaction. The decomposition rate is slow at 450-500℃, and the generated Li2O (alkaline oxide, sulfur-fixing core active species) can react with SO4 in the melt in time. 2- reaction to avoid the volatilization and loss of Li2O; the oxidizing gases NO2 and O2 generated at the same time can form a "micro-oxidizing atmosphere" on the melt surface, further inhibiting SO4 2- Reduction, avoid the presence of reducing substances in the sample to reduce SO4 2- Reduction. At the same time, the internal grid structure of the flux lithium tetraborate and lithium metaborate changes between 450-500°C, transforming into a long-chain boron-oxygen network (-BOB-). This network can help form a homogeneous environment, reduce the viscosity of the system, promote ion diffusion, and form a high-temperature melt in the subsequent high-temperature melt. It can also evenly disperse and fix the sulfur element (in the form of Li2SO4) through the "skeleton effect" of the boron-oxygen network, laying the foundation for the sulfur stability of the subsequent high-temperature melt. In the boron-oxygen-lithium nitrate mixed melt, Li2SO4 forms a "Li2SO4 microcrystalline dispersion" through "boron-oxygen network wrapping" - boron-oxygen oligomers (BO chains) are wrapped around the surface of the Li2SO4 microcrystals, preventing the microcrystals from agglomerating, so that the sulfur element is stably locked in the melt in the form of Li2SO4, avoiding sulfur volatilization (lithium ions have a small radius and strong polarization ability, and the bonds formed with sulfate groups are stronger).

[0011] Different from the existing technology, the standard test product adopts melting treatment to eliminate the mineral effect, overcome the particle size effect, and reduce the measurement error; lithium nitrate, anhydrous lithium tetraborate and lithium metaborate flux are added before melting, and a pre-melting step is performed at 450-500℃ for 20 minutes. The lithium nitrate, lithium tetraborate and lithium metaborate work synergistically to fix the sulfur element in anhydrous sodium sulfate and prevent the volatilization of the sulfur element, thereby improving the accuracy of the test results. At the same time, it can also reduce the melting temperature and save energy.

[0012] Furthermore, the mass ratio of the standard sample to the flux is 1:7-10; and the flux is a mixed flux of anhydrous lithium tetraborate and lithium metaborate.

[0013] Further, the lithium nitrate is added in an amount of 50-100% of the mass of the standard sample.

[0014] Further, the particle size of the anhydrous sodium sulfate, sodium chloride, and iron oxide is not more than 200 mesh; the anhydrous sodium sulfate and sodium chloride are dried at 105°C for more than 2 hours before use.

[0015] Further, the iron oxide is mixed using a 0.1 mg / ml iron oxide standard solution.

[0016] Further, the content of the anhydrous sodium sulfate is 90%-99.99%, the content of the sodium chloride is 0-10%, and the content of the Fe2O3 is 0-100 ppm.

[0017] The second aspect of the present application provides a mirabilite XRF component detection method, comprising the following steps: pretreatment: uniformly mixing a to-be-detected mirabilite sample with a fluxing agent and lithium nitrate to obtain a mixed sample; pre-melting the mixed sample at 450-500°C for 20 minutes, and then melting at 900°C-1050°C for 15-25 minutes to obtain a detection sample after natural cooling;

[0018] XRF detection: placing the detection sample into an X-ray fluorescence spectrometer to detect the Kcps value of S, Cl, and Fe elements in the detection sample;

[0019] Analysis and calculation: substituting the detection result into the standard working curve constructed in the first aspect of the present application to calculate the content of sodium sulfate, sodium chloride, and iron oxide in the mirabilite sample.

[0020] Compared with the prior art, the to-be-detected sample is treated by melting, which eliminates the mineral effect, overcomes the particle size effect, and reduces the measurement error; lithium nitrate, anhydrous tetraborate, and metaborate fluxing agents are added before melting, a pre-melting step at 450-500°C is added, and the lithium nitrate, tetraborate, and metaborate fluxing agents work together to fix the sulfur element in the anhydrous sodium sulfate, prevent the sulfur element from volatilizing, improve the accuracy of the detection result, and also reduce the melting temperature and save energy.

[0021] Further, the mass ratio of the to-be-detected mirabilite sample to the fluxing agent is 1:7-10; the fluxing agent is a mixed fluxing agent of anhydrous tetraborate and metaborate.

[0022] Further, the lithium nitrate is added in an amount of 50-100% of the mass of the mirabilite sample.

[0023] Further, the particle size of the to-be-detected mirabilite sample is not more than 200 mesh.

[0024] The above summary related to the description is only a summary of the technical scheme of the present application, in order to enable those skilled in the art to more clearly understand the technical scheme of the present application, and then can be implemented according to the content of the description and the drawings, and in order to let the above purpose and other purposes, characteristics and advantages of the present application can be more easily understood, the following is described in combination with the specific embodiments of the present application and the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0025] The drawings are only used to show the principles, implementation modes, applications, characteristics and effects of the specific embodiments of the present application and other related contents, and cannot be considered as a limitation of the present application.

[0026] In the drawings of the specification:

[0027] Figure 1 The standard working curve of the content of Na2SO4 and the Kcps value of S element in the specific embodiments of the present application;

[0028] Figure 2 The standard working curve of the content of NaCl and the Kcps value of Cl element in the specific embodiments of the present application;

[0029] Figure 3 The standard working curve of the content of Fe2O3 and the Kcps value of Fe element in the specific embodiments of the present application. DETAILED DESCRIPTION

[0030] In order to explain the possible application scenarios, technical principles, specific schemes that can be implemented, and the purposes and effects that can be achieved of the present application in detail, the following will be described in combination with the specific embodiments listed and the drawings. The embodiments described in this paper are only used to more clearly illustrate the technical scheme of the present application, therefore, only as an example, and cannot limit the protection scope of the present application.

[0031] In this paper, the term "embodiment" means that the specific features, structures or characteristics described in combination with the embodiment can be included in at least one embodiment of the present application. The term "embodiment" appearing in various places in the specification does not necessarily refer to the same embodiment, and does not particularly limit the independence or association between other embodiments. In principle, in the present application, as long as there is no technical contradiction or conflict, the technical features mentioned in each embodiment can be combined in any way to form a corresponding implementable technical scheme.

[0032] Unless otherwise defined, the meaning of the technical terms used in this paper is the same as that generally understood by those skilled in the art to which the present application belongs; the use of related terms in this paper is only for the purpose of describing specific embodiments, and is not intended to limit the present application.

[0033] In the description of the present application, the phrase "and / or" is a description of a logical relationship between objects, which means that there can be three relationships, for example, A and / or B, which means that there are three cases: A exists, B exists, and A and B exist at the same time. In addition, the character " / " herein generally represents that the associated objects before and after are an "or" logical relationship.

[0034] In the present application, phrases such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual quantity, primary and secondary, or order relationship between the entities or operations.

[0035] In the present application, without more limitation, the "includes", "contains", "has" or other similar expressions used in the sentence are intended to cover non-exclusive inclusion, and these expressions do not exclude the presence of other elements in the process, method or product including the described elements, so that the process, method or product including a series of elements can not only include those limited elements, but also include other elements not explicitly listed, or also include elements inherent to such process, method or product.

[0036] As the same understanding as in the "Guidelines for Review", in the present application, the expressions such as "greater than", "less than", "exceed" are understood as not including the number; the expressions such as "above", "below", "within" are understood as including the number. In addition, in the description of the embodiments of the present application, the meaning of "multiple" is more than two (including two), and similar expressions related to "multiple" are also understood in this way, for example, "multiple groups", "multiple times" and the like, unless otherwise explicitly limited.

[0037] The first aspect of the present application discloses a method for constructing a standard working curve for mirabilite XRF detection, comprising the following steps:

[0038] Preparation of standard sample: gradient mixing of anhydrous sodium sulfate, sodium chloride and iron oxide according to predetermined content to obtain more than three standard samples;

[0039] Preparation of standard detection product: uniformly mixing the standard sample with fluxing agent and lithium nitrate, then pre-melting at 450-500℃ for 20 minutes, and then melting at 900℃-1050℃ for 15-25 minutes, and then naturally cooling to obtain the standard detection product;

[0040] Drawing of standard working curve: placing the standard detection product into an X-ray fluorescence spectrometer, detecting the Kcps values of S, Cl and Fe elements respectively, and drawing a standard working curve for mirabilite XRF detection corresponding to the contents of sodium sulfate, sodium chloride and iron oxide.

[0041] Lithium nitrate completely melts at 253℃, starts to decompose slowly at 450℃, generating Li2O, NO2 and O2, releasing sulfur-fixing active species, and will decompose violently above 500℃, leading to sample splashing loss and incomplete reaction. The decomposition rate is slow between 450-500℃, and the generated Li2O (basic oxide, sulfur-fixing core active species) can react with SO4 2- in the melt in time to avoid the loss of Li2O volatilization; at the same time, the generated NO2 and O2 oxidizing gas can form a "micro-oxidizing atmosphere" on the surface of the melt, further inhibiting the SO4 2- reduction, avoiding the presence of reducing substances in the sample to reduce SO4 2- reduction. At the same time, the fluxes lithium tetraborate and lithium metaborate change their internal grid structure between 450-500℃, transforming into long-chain boron-oxygen networks (-B-O-B-), which can help form a homogeneous environment, reduce system viscosity, promote ion diffusion, and help form a high-temperature melt sheet in the subsequent process. The boron-oxygen network also has a "skeleton effect" that can uniformly disperse and fix sulfur elements (in the form of Li2SO4), laying the foundation for sulfur stability in the subsequent high-temperature melt sheet. Li2SO4 in the boron-oxygen-nitrate lithium mixed melt can form "Li2SO4 microcrystalline dispersion" through "boron-oxygen network wrapping" - the boron-oxygen oligomer (B-O chain) is wrapped around the surface of the Li2SO4 microcrystal, preventing microcrystal agglomeration and allowing sulfur elements to be stably locked in the form of Li2SO4 in the melt, avoiding sulfur volatilization (lithium ion radius is small, polarization ability is strong, and the bond formed with sulfate is more stable).

[0042] Unlike existing technologies, the standard test sample uses a melting process to eliminate mineral effects, overcome particle size effects, and reduce measurement errors. Lithium nitrate, lithium tetraborate, and lithium metaborate fluxes are added before melting, and a pre-melting step of 450-500℃ for 20 minutes is used. The synergistic effect of lithium nitrate, lithium tetraborate, and lithium metaborate fixes the sulfur elements in anhydrous sodium sulfate, preventing sulfur element volatilization, improving the accuracy of test results, and also reducing the melting temperature and saving energy.

[0043] Further, the mass ratio of the standard sample to the flux is 1:7-10; the flux is a mixed flux of anhydrous lithium tetraborate and lithium metaborate.

[0044] Further, the amount of lithium nitrate added is 50-100% of the mass of the standard sample.

[0045] Further, the particle size of the anhydrous sodium sulfate, sodium chloride, and iron oxide is not more than 200 mesh; the anhydrous sodium sulfate and sodium chloride are dried at 105℃ for more than 2 hours before use.

[0046] Further, the 0.1 mg / ml iron oxide standard solution is used when mixing the iron oxide gradient.

[0047] Further, the content of the anhydrous sodium sulfate is 90%-99.99%, the content of the sodium chloride is 0-10%, and the content of the Fe2O3 is 0-100ppm.

[0048] The second aspect of the present application provides a method for detecting the components of mirabilite by XRF, comprising the following steps: pretreatment: uniformly mixing the sample to be detected with flux and lithium nitrate to obtain a mixed sample; pre-melting the mixed sample at 450-500℃ for 20 minutes, and then melting it at 900℃-1050℃ for 15-25 minutes to obtain a detection sample;

[0049] XRF detection: placing the detection sample into an X-ray fluorescence spectrometer to detect the Kcps values of S, Cl and Fe elements in the detection sample;

[0050] Analysis and calculation: substituting the detection results into the standard working curve constructed in the first aspect of the present application to obtain the contents of sodium sulfate, sodium chloride and iron oxide in the mirabilite sample.

[0051] Compared with the prior art, the sample to be detected is treated by melting, which eliminates the mineral effect, overcomes the particle size effect and reduces the measurement error; anhydrous lithium nitrate, lithium tetraborate and lithium metaborate flux are added before melting, a pre-melting step at 450-500℃ is added, and the three fluxes cooperate to fix the sulfur element in the anhydrous sodium sulfate and prevent the sulfur element from volatilizing, thereby improving the accuracy of the detection results and also reducing the melting temperature and saving energy.

[0052] Further, the mass ratio of the sample to be detected to the flux is 1:7-10; and the flux is a mixed flux of anhydrous lithium tetraborate and lithium metaborate.

[0053] Further, the amount of lithium nitrate added is 50-100% of the mass of the mirabilite sample.

[0054] Further, the particle size of the sample to be detected is not more than 200 mesh.

[0055] The mixed flux of anhydrous lithium tetraborate and lithium metaborate used in the present embodiment is purchased from Luoyang Tena Experimental Equipment Co., Ltd.; and the mirabilite reference reagent is purchased from Fuchen Chemical (Tianjin) Chemical Reagent Co., Ltd.

[0056] In the present embodiment, the purity of the anhydrous sodium sulfate is ≥99.9%, the purity of the sodium chloride is ≥99.99%, the purity of the iron oxide is ≥99.99%, and the particle size of all of them is not more than 200 mesh; and the purity of the lithium nitrate is ≥99.99%.

[0057] Preparation of standard detection products 1-5 in Example 1

[0058] 1. Design 5 standard samples of the standard curve series of Glauber's salt according to the gradient of each component (see Table 1); among them, the designed component of sodium sulfate is 90%-99.99%, the designed component of sodium chloride is 0-10%, and the designed component of iron oxide is 10-100ppm, and the total amount is 99%-101%.

[0059] 2. Weigh and mix anhydrous sodium sulfate, sodium chloride, and iron oxide, mix them evenly with lithium nitrate (the amount added is set according to Table 1), and stir evenly to obtain a mixed sample; the anhydrous sodium sulfate and sodium chloride are dried at 105°C for more than 2 hours before use; the iron oxide is added using a prepared 0.1 mg / ml iron oxide standard solution using a 0-1000 μl pipette to improve the accuracy and operability of the standard sample.

[0060] 3. Place the weighed flux anhydrous lithium tetraborate and lithium metaborate in a platinum crucible. To prevent lithium nitrate from damaging the platinum crucible, spread the aforementioned mixed sample on the surface of the flux. It must not directly contact the platinum crucible. Finally, evenly add 4 drops of 20% ammonium bromide release agent on the surface.

[0061] 4. Turn on the melting machine, set the heating curve, put the crucibles into the preheated melting machine one by one, cover the furnace cover, and melt the sample. The pre-melting temperature is 450℃, the pre-melting time is 20 minutes, and the melting temperature is 950℃, and the melting time is 20 minutes.

[0062] 5. After melting the sample, take out the crucible and place it on a high temperature resistant pad to cool naturally.

[0063] 6. After cooling, the samples are demoulded and taken out, and numbered to obtain standard test products 1-5.

[0064] The specific process parameters for the preparation of standard test products are shown in Table 1.

[0065] Table 1 Process parameters of standard test products of Glauber's salt

[0066] Standard 1 Standard 2 Standard 3 Standard 4 Standard 5 Na2SO4 / % 99.99 99.00 98.00 95.00 90.00 NaCI / % 0.00 1.00 2.00 5.00 10.00 Fe203 / ppm 10 20 40 60 100 High purity sodium sulfate g 0.7000 0.6931 0.6861 0.6651 0.6301 High purity sodium chloride g 0.0000 0.0070 0.0140 0.0350 0.0700 High purity iron oxide g 0.000007 0.000014 0.000028 0.000042 0.00007 Lithium nitrate g 0.7 0.7 0.7 0.7 0.7 Mixed flux g 7 7 7 7 7 Pre-melt temperature °C 450 450 450 450 450 Pre-melt time min 20 20 20 20 20 Melt temperature °C 950 950 950 950 950 Melt time min 20 20 20 20 20 Release agent / drops 4 4 4 4 4

[0067] Example 2 Establishment of XRF Detection Standard Working Curve

[0068] The five standard test products prepared in Example 1 were used to detect the Kcps values ​​of S, Cl and Fe elements respectively on a fluorescence spectrometer, and a standard working curve was established corresponding to the contents of sodium sulfate, sodium chloride and iron oxide. Figure 1-3 The scanning speed of sodium chloride is not higher than 1° / min, and the scanning speed of iron oxide is not higher than 0.5° / min;

[0069] 1. If Figure 1As shown, the fitting equation y1 = 1.3675x1-0.5971, wherein y1 is the content of Na2SO4 in mirabilite, x1 is the Kcps value of S element, the correlation coefficient R 2 = 0.9999;

[0070] 2, as shown in Figure 2 the fitting equation y2 = 1.0849x2 + 0.0611, wherein y2 is the content of NaCl in mirabilite, x2 is the Kcps value of Cl element, the correlation coefficient R 2 = 0.9999;

[0071] 3, as shown in Figure 3 the fitting equation y3 = 1.0849x3 + 0.0611, wherein y3 = 0.0026x3 + 0.3924, wherein y3 is the content of Fe2O3 in mirabilite, x3 is the Kcps value of Fe element, the correlation coefficient R 2 = 0.9991.

[0072] Example 3 standard curve and detection method verification:

[0073] 1, design and construct the calibration 1 and calibration 2 as shown in Table 2. The construction design method is the same as Example 1.

[0074] 2, calibration pretreatment: after adding lithium nitrate to the calibration, mix evenly to obtain a mixed sample, spread on the flux placed in the platinum crucible, do not directly contact the platinum crucible, add 4 drops of 20% ammonium bromide release agent on the surface; the mixed sample is melted, the pre-melting temperature is 450℃, the pre-melting time is 20 minutes, the melting temperature is 950℃, the melting time is 20 minutes, and the natural cooling obtains the calibration detection sample (the process parameters are the same as Example 1);

[0075] 3, fluorescence detection: the calibration detection sample is placed in the X-ray fluorescence spectrometer, and the Kcps value of S, Cl and Fe in the detection sample is detected; the standard working curve of Example 2 is used for analysis and calculation, and the detection value of each component is shown in Table 2.

[0076] Table 2 calibration detection result comparison table

[0077]

[0078] By comparing the design value and the detection value, the measurement result is within the allowable error range, the measurement result is high in accuracy, and it is proved that the above-mentioned standard working curve and method are reliable.

[0079] Example 4 mirabilite reference reagent detection:

[0080] The mirabilite reference reagent (sodium sulfate 99.9%, sodium chloride 0.1%, iron oxide 5ppm) is pre-melted at 450-500℃ for 20 minutes, then melted at 900℃-1050℃ for 15-25 minutes, and the detection sample is obtained by natural cooling; XRF detection: the detection sample is placed into an X-ray fluorescence spectrometer, and the Kcps values of S, Cl, and Fe elements in the detection sample are detected; the detection results are substituted into the standard working curve of Example 2, and the actual measurement of sodium sulfate is 99.890%, sodium chloride is 0.103%, and iron oxide is 6ppm.

[0081] Example 5: Mirabilite detection:

[0082] Mirabilite sample (chemical analysis results: sodium sulfate 99.448%, sodium chloride 0.311%, iron oxide 16ppm) pretreatment: the mirabilite sample to be detected is added with lithium nitrate, mixed uniformly to obtain a mixed sample, and then is laid on a fluxing agent placed in a platinum crucible without directly contacting the platinum crucible, and finally 4 drops of 20% ammonium bromide release agent are added uniformly on the surface; the mixed sample is pre-melted at 450-500℃ for 20 minutes, then melted at 900℃-1050℃ for 15-25 minutes, and the detection sample is obtained by natural cooling;

[0083] The detection sample is placed into an X-ray fluorescence spectrometer, and the Kcps values of S, Cl, and Fe elements in the detection sample are detected; the detection results are substituted into the standard working curve of Example 2 for calculation, and the contents of sodium sulfate, sodium chloride, and iron oxide in the mirabilite sample are 99.529%, 0.325%, and 18ppm respectively.

[0084] The technical scheme of the present application performs full-component analysis on the components of mirabilite, and directly analyzes and determines the impurities NaCl and Fe2O3, the analysis method is simple to operate, fully automatic, and high in detection efficiency; the detection sample is prepared by the fusion disc method, the sample is completely and uniformly melted, the mineral effect is eliminated, the particle size effect is overcome, and the measurement error is reduced; the synergistic effect of lithium nitrate, lithium tetraborate, and lithium metaborate fixes the sulfur element in anhydrous sodium sulfate, prevents the volatilization of the sulfur element, and improves the accuracy of the detection results; meanwhile, the melting temperature can be reduced, and energy consumption can be saved.

[0085] Finally, it should be noted that although the above embodiments have been described in the specification and drawings of the present application, the patent protection scope of the present application should not be limited. Any technical scheme obtained by replacing or modifying the equivalent structure or equivalent flow based on the essential concept of the present application, using the content described in the specification and drawings of the present application, and directly or indirectly implementing the technical scheme of the above embodiments in other related technical fields, is included in the patent protection scope of the present application.

Claims

1. A method for constructing a standard working curve for Sodium Sulfate XRF detection, characterized in that: The construction method comprises the following steps: Preparation of standard samples: Anhydrous sodium sulfate, sodium chloride, and iron oxide are mixed in a gradient according to predetermined contents to obtain three or more standard samples; Preparation of standard test products: After uniformly mixing the standard sample with flux and lithium nitrate, pre-melt at 450-500°C for 20 minutes, then melt at 900-1050°C for 15-25 minutes, and naturally cool to obtain the standard test product; Standard working curve drawing: the standard test sample is placed in an X-ray fluorescence spectrometer to detect the Kcps values ​​of S, Cl, and Fe elements respectively, and a standard working curve of mirabilite XRF detection is drawn corresponding to the contents of sodium sulfate, sodium chloride, and iron oxide.

2. The construction method according to claim 1, characterized in that The mass ratio of the standard sample to the flux is 1:7-10; the flux is a mixed flux of anhydrous lithium tetraborate and lithium metaborate.

3. The construction method according to claim 1, characterized in that The amount of lithium nitrate added is 50-100% of the mass of the standard sample.

4. The construction method according to claim 1, wherein The particle size of the anhydrous sodium sulfate, sodium chloride and iron oxide does not exceed 200 mesh; the anhydrous sodium sulfate and sodium chloride are dried at 105° C. for more than 2 hours before use.

5. The construction method according to claim 1, characterized in that The iron oxide gradient mixing adopts 0.1 mg / ml iron oxide standard solution.

6. The construction method according to claim 1, characterized in that The content of the anhydrous sodium sulfate is 90%-99.99%, the content of the sodium chloride is 0-10%, and the content of the Fe2O3 is 0-100ppm.

7. A method for detecting the composition of mirabilite by XRF, characterized in that: The following steps are involved: Pretreatment: Mix the thenardite sample to be tested with flux and lithium nitrate to obtain a mixed sample; pre-melt the mixed sample at 450-500°C for 20 minutes, then melt at 900-1050°C for 15-25 minutes, and cool naturally to obtain a test sample; XRF detection: Place the test sample into an X-ray fluorescence spectrometer to detect the Kcps values ​​of S, Cl, and Fe elements in the test sample; Analysis and calculation: Substitute the test results into the standard working curve constructed by the method of any one of claims 1 to 6 to calculate and obtain the content of sodium sulfate, sodium chloride and iron oxide in the mirabilite sample.

8. The detection method according to claim 7, characterized in that The mass ratio of the tested sodium sulfate sample to the flux is 1:7-10; the flux is a mixed flux of anhydrous lithium tetraborate and lithium metaborate.

9. The detection method according to claim 7, characterized in that The amount of lithium nitrate added is 50-100% of the mass of the Glauber's salt sample.

10. The detection method according to claim 7, characterized in that: The particle size of the thenardite sample to be tested does not exceed 200 meshes.

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