Method for quantitatively detecting molybdenum content in molybdenum concentrate through niobium internal standard X-ray fluorescence spectrum

Abstract

The invention belongs to the technical field of analytical chemistry-instrument analysis quantitative detection, and particularly discloses a method for quantitatively detecting the molybdenum content in molybdenum concentrate through niobium internal standard X-ray fluorescence spectrum, and the molybdenum content in a molybdenum concentrate product is quantitatively detected through a niobium internal standard X-ray fluorescence spectrum melting method. The method solves the problem of large fluctuation of a high-grade molybdenum content measurement result in an existing X-ray fluorescence spectrum technology, has excellent accuracy and precision, has a niobium internal standard method basically consistent with a YS / T 555.1 analysis result in mixed sample detection of molybdenum product and ferromolybdenum deep processing enterprises, meets the applicability requirements of measurement of different mine samples, and has a wide application prospect. According to the method, the niobium internal standard is adopted, so that the sample matrix effect, the mineral effect and the difference of different testing instruments are reduced, and the actual application process meets the molybdenum concentrate related sales analysis standard.

Description

Technical Field

[0001] The invention belongs to the technical field of analytical chemistry-instrumental analysis and quantitative detection, and specifically discloses a method for quantitatively detecting the amount of molybdenum in molybdenum concentrate using a niobium internal standard X-ray fluorescence spectrum. Background Art

[0002] In the standard requirements for molybdenum concentrate products, different grades are divided according to different molybdenum grades. The current industry standard YS / T555.1 method indicates that the allowable difference is less than 0.40%. The accurate determination of the molybdenum grade of molybdenum concentrate is particularly important for the grading of molybdenum concentrate products.

[0003] The quantitative analysis of molybdenum by X-ray fluorescence spectrometry melting method is a highly sensitive measurement technology that uses X-ray technology to convert the excitation fluorescence intensity of molybdenum elements into electrical signals. It is completely different from the mechanism of analyzing molybdenum content by lead molybdate precipitation method required by YS / T 555.1. At present, in the reports on the determination of molybdenum concentrate by X-ray fluorescence spectrometry melting method, the determination range of molybdenum is between 0.15~65%, and the RSD is between 0.066~0.58%, which can meet the general production requirements, but the detection precision is not ideal, the applicability of determination of samples from different mines is inconsistent, and it cannot meet the high detection standard requirements. The internal standard method has been widely used in the quantitative analysis of X-ray fluorescence spectrometry, and its accuracy and precision have great advantages. Some methods have been recognized by national standards and industry standards. For example, Gao Xinhua et al. used the internal standard method to determine the zirconium content in niobium alloy, which effectively reduced the difficulty of analysis; Zhang Lixin et al. discussed the application research of X-ray fluorescence spectrometry internal standard method in the determination of iron content in iron ore, and the analysis results were consistent with chemical analysis. Summary of the invention

[0004] In order to solve the problem in the background technology, the present invention discloses a method for quantitatively detecting the amount of molybdenum in molybdenum concentrate by using niobium internal standard X-ray fluorescence spectroscopy. The method adopts the niobium internal standard X-ray fluorescence spectroscopy melting method to quantitatively detect the amount of molybdenum in the molybdenum concentrate product, thereby solving the problem of large fluctuations in the high-grade molybdenum content determination results in the existing X-ray fluorescence spectroscopy technology.

[0005] In order to achieve the above-mentioned invention object, the present invention adopts the following technical scheme:

[0006] A method for quantitatively detecting the amount of molybdenum in molybdenum concentrate by using niobium internal standard X-ray fluorescence spectrometry comprises the following steps:

[0007] (1) Preparation of test standard samples: According to the YS / T 555.1 method, the internal control sample of molybdenum concentrate is determined. After drying, multiple internal control samples of different concentrations are selected according to a certain concentration gradient. A certain amount of the internal control sample, solid flux, oxidant, release agent and internal standard are weighed respectively. First, part of the solid flux is spread in a platinum crucible, and the weighed internal control sample, oxidant and internal standard are added to the solid flux spread in the platinum crucible, and the remaining solid flux is used to cover the internal control sample, oxidant and internal standard. The temperature is kept at 750°C for 5 minutes. Finally, the release agent is dripped into the platinum crucible. The melting procedure is pre-melting at 1050°C for 120 seconds, shaking for 600 seconds, and standing for 60 seconds to prepare test standard samples respectively;

[0008] (2) Establishing a test standard curve: Place the test standard samples prepared in step (1) on a wavelength dispersive spectrometer to measure the fluorescence intensity, and use the fluorescence ratio intensity of molybdenum and niobium elements as the horizontal axis and the mass fraction of molybdenum in the corresponding standard sample determined according to the YS / T 555.1 method as the vertical axis to prepare a standard sample working curve;

[0009] (3) Determination of the amount of molybdenum in molybdenum concentrate: Weigh a certain amount of molybdenum concentrate sample, solid flux, oxidant, release agent and internal standard, prepare the sample according to the preparation conditions of step (1), and then measure the fluorescence intensity ratio of molybdenum and niobium elements in the sample according to the test conditions of step (2). Calculate the amount of molybdenum in the molybdenum concentrate sample based on the working curve of the standard sample prepared in step (2).

[0010] Furthermore, in the method for quantitatively detecting the amount of molybdenum in molybdenum concentrate by using niobium internal standard X-ray fluorescence spectroscopy, the internal standard is niobium pentoxide.

[0011] Furthermore, in the method for quantitatively detecting the amount of molybdenum in molybdenum concentrate using niobium internal standard X-ray fluorescence spectrometry, the solid flux is a mixture of anhydrous lithium tetraborate and lithium metaborate in a mass ratio of 12:22, and the mass ratio of the solid flux to the sample is 12:1.

[0012] Furthermore, in the method for quantitatively detecting the amount of molybdenum in molybdenum concentrate by using niobium internal standard X-ray fluorescence spectrometry, the oxidant is solid lithium nitrate or a lithium nitrate solution with a mass fraction of 50%.

[0013] Furthermore, in the method for quantitatively detecting the amount of molybdenum in molybdenum concentrate using niobium internal standard X-ray fluorescence spectroscopy, the release agent is an ammonium bromide or lithium bromide solution with a mass fraction of 30%-40%.

[0014] Furthermore, in the method for quantitatively detecting the amount of molybdenum in molybdenum concentrate by niobium internal standard X-ray fluorescence spectrometry, the test conditions in step (2) are that the analysis line of molybdenum is Mo Lβ, and the internal standard line of internal standard niobium is Nb Lβ, wherein the wavelength range of Mo Lβ line is 0.4920-0.5177 nm, and the absorption limit is 0.4914 nm; the wavelength of Nb Lβ line is 0.5234-0.5491 nm, and the absorption limit is 0.5223 nm.

[0015] Furthermore, in the method for quantitatively detecting the amount of molybdenum in molybdenum concentrate using niobium internal standard X-ray fluorescence spectroscopy, the mass fraction of molybdenum in the internal control sample ranges from 20.00% to 60.00%.

[0016] Furthermore, the method for quantitatively detecting the amount of molybdenum in molybdenum concentrate by using niobium internal standard X-ray fluorescence spectroscopy includes automatically correcting the matrix effect of the fluorescence ratio intensity of molybdenum and niobium using formula (1):

[0017] ω Mo =[I Mo / I Nb ×A0+A1] / M Mo ×100% (1)

[0018] in:

[0019] ω Mo - Corrected Mo content;

[0020] I Mo - Fluorescence intensity of Mo in the sample, Kcps;

[0021] I Nb - Fluorescence intensity of Nb in the sample, Kcps;

[0022] A0 - slope of the calibration curve;

[0023] A1 - intercept of the calibration curve;

[0024] M Mo - Test sample weight, g.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The method of quantitatively detecting the amount of molybdenum in molybdenum concentrate by using niobium internal standard X-ray fluorescence spectroscopy in the present invention has excellent accuracy and precision. In the detection of mixed samples of molybdenum products and ferromolybdenum deep processing enterprises, the niobium internal standard method is basically consistent with the analysis results of YS / T 555.1, meets the applicability requirements of the determination of samples from different mines, and meets the requirements of high detection standards. The present invention uses niobium internal standard to reduce the sample matrix effect, mineral effect and differentiation of different testing instruments, and the actual application process meets the relevant sales analysis standards for molybdenum concentrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a comparison diagram of the X-ray fluorescence response intensity ratio level of molybdenum and niobium and the fitting curve of the mass fraction of molybdenum element in the sample when the amount of the internal standard (Nb2O5) added is different in the present invention;

[0028] Figure 2 The positional relationship between the molybdenum, niobium and matrix spectral lines and their corresponding absorption limits of the present invention;

[0029] Figure 3 It is the standard working curve of the X-ray fluorescence response intensity ratio of molybdenum and niobium and the mass fraction of the molybdenum element in the present invention. DETAILED DESCRIPTION

[0030] The following is a further detailed description of the method for quantitatively detecting the amount of molybdenum in molybdenum concentrate by niobium internal standard X-ray fluorescence spectroscopy of the present invention. It should be understood that the following examples are only exemplary descriptions and explanations of the present invention, and should not be construed as limiting the scope of protection of the present invention. All technologies realized based on the above content of the present invention are included in the scope of protection of the present invention. In addition, unless otherwise specified, the reagents involved in the examples are commercially available products.

[0031] <Materials and Reagents>

[0032] The internal control sample of molybdenum concentrate is assigned according to the current industry standard YS / T 555.1. The molybdenum content range of the internal control sample is: 20.00~60.00%;

[0033] Methane-argon: 90%-10%;

[0034] Platinum crucible: used to prepare standard samples, made of platinum: gold = 98:2, inner diameter 40mm;

[0035] Nickel crucible: used to mix solid reagents and samples;

[0036] Niobium pentoxide (Nb2O5): purity better than 99.99%, Sinopharm Chemical Reagent Co., Ltd.;

[0037] Lithium nitrate, lithium bromide, ammonium bromide: analytical grade, Sinopharm Chemical Reagent Co., Ltd.;

[0038] Anhydrous lithium tetraborate: lithium metaborate (12:22): high purity, Luoyang Haina Reagent.

[0039] <Main instruments and equipment>

[0040] ZSX Primus IV wavelength dispersive X-ray fluorescence spectrometer: maximum power 4kW, ultra-thin window, end-window rhodium target X-ray tube, ZSX Guidance software, analysis range Be~U, Rigaku Corporation, Japan;

[0041] Analytical balance: precision 0.0001 g, METTLER TOLEDO, Switzerland;

[0042] Automatic weighing prototype: accuracy 0.0001 g, 20 card slots, Luoyang Chaonai Instrument Factory.

[0043] Muffle furnace: with program temperature control function, Luoyang Chaonai Instrument Factory.

[0044] High temperature melting furnace: automatic melting program, Luoyang Chaonai Instrument Factory.

[0045] <Choice of internal standard>

[0046] As an external additive in the test process, the internal standard should have the following characteristics: high-purity material, stable existence (laboratory conditions and high-temperature melting process), particle size similar to the analyte, relatively low price, easy to obtain, etc. There are many niobium compounds available on the market, and the main ones commonly used in laboratories are NbO(NO3)3, niobium pentahalide (NbX5), niobium nitride (NbN), and niobium oxides (Nb2O5, NbO2, Nb2O3, NbO). The first three categories have disadvantages such as low melting point, easy decomposition, and easy moisture absorption, and are not suitable as internal standards. The most stable niobium oxide is niobium pentoxide, which has high commercial purity, low price, and is not reducible under high temperature conditions. Therefore, the internal standard of this method selects niobium pentoxide with a purity of 4N (99.99%) level;

[0047] The application of X-ray fluorescence spectrometry internal standard method requires that the content of the internal standard element in the test material is not in the same order of magnitude as the test addition amount. Molybdenum concentrate sample is a product obtained after flotation enrichment of ores such as molybdenite. The requirements for impurities are clearly stated in the relevant product grades, and niobium is not considered as an impurity element. In order to investigate the approximate content range of niobium in molybdenum concentrate, 40 representative samples were randomly inspected from different mines and different batches of products. The niobium content in the representative samples was between 60.00-105.00 ppm, which is not in the same order of magnitude compared with the amount of high-purity niobium added during the sample preparation process (0.5000 g, 7.692% by mass). The experimental results show that the niobium content of the molybdenum concentrate sample itself has a negligible effect on the detection of the molybdenum concentrate product, eliminating the possibility that the sample itself contains niobium and causes inaccurate results;

[0048] When the analytical lines of different elements have similar wavelengths, the premise of the internal standard is that the fluorescence measurement intensity is similar when the mass fraction is similar. In order to obtain the best test conditions, the relationship between the fluorescence intensity ratio of the Lβ line of Mo and the Lβ line of Nb and the amount of niobium added is explored. For details, see Figure 1 .

[0049] Figure 1The results show that the amount of niobium added directly affects the fluorescence intensity ratio of Mo and Nb, and when the amount of niobium added is constant, the fluorescence intensity ratio of Mo and Nb is linearly related to the content of molybdenum within a certain range. This is related to the principle of fluorescence testing, that is, when the intensity reaches a certain range, the probability of the counter missing increases. Therefore, the standard curve method has a certain basis for determination. Using Nb as the internal standard for Mo determination can effectively reduce the interference of matrix effect. Therefore, when the Mo mass fraction is in the range of 20-60%, the analysis line intensity ratio of Mo and Nb is relatively stable, and Nb can be used as an internal standard to determine the Mo content.

[0050] <Selection of internal standard analysis line>

[0051] For the selection of internal standard elements in the determination process of the internal standard method, it is required that the absorption and enhancement effects of the internal standard elements and the analyzed elements should be basically the same, and meet the following conditions: ① The analytical lines of the analyzed element and the internal standard and their respective absorption limits (close to each other) do not interfere with each other; ② The wavelengths and absorption limits of the analyzed element, the internal standard and the matrix element are all on the same side. In this method, the wavelength range of the Mo Lβ line is 0.4920~0.5177 nm, and the absorption limit is 0.4914 nm; the wavelength of the Nb Lβ line is 0.5234~0.5491 nm, and the absorption limit is 0.5223 nm. The main components of the standard sample and the test sample are Si, and the impurity elements P, Ca, S, etc. The positions of the spectral lines of the analyzed element, internal standard element and matrix element and their corresponding absorption limits are shown in Figure 2 The wavelength and absorption limit of the Lβ line of Mo are close to those of the Lβ line of Nb, and are both located on the left side of the detection wavelength as well as the absorption limit of the matrix elements. In addition, the absorption and enhancement effects of Mo and Nb are highly similar, which meets the theoretical requirements. Therefore, considering the mutual influence of X-ray analysis spectra, the Lβ line of Nb has good theoretical support as the internal standard line of the Lβ line of Mo.

[0052] <Test condition selection>

[0053] The instrumental analysis conditions of molybdenum and niobium elements should be optimized. The test conditions of the present invention include the following key points: X-ray tube power, analysis line, spectroscopic crystal, collimator, detector, PHD, background, counting time, etc. The final test conditions are listed in Table 1.

[0054] Table 1 Mo and Nb element analysis conditions

[0055]

[0056] <Preparation of test samples>

[0057] Weigh 0.5000±0.0002 g of sample (baked at 105℃ for 2 h), internal standard: 0.5000±0.0002 g of niobium pentoxide (baked at 750℃ for 2 h), oxidant is 0.50 mL of 50% lithium nitrate solution or an equal amount of lithium nitrate solid particles, first take 3.0000±0.0002 g (anhydrous lithium tetraborate: lithium metaborate mixed flux = 12:22, baked at 750℃ for 2 h) of solid flux and spread it in a platinum crucible, then put the weighed sample, oxidant and internal standard on the solid flux spread in the platinum crucible, then take another 3.0000±0.0002 g (anhydrous lithium tetraborate: lithium metaborate mixed flux = 12:22, baked at 750℃ for 2 h) of solid flux and spread it in a platinum crucible, then put the weighed sample, oxidant and internal standard on the solid flux spread in the platinum crucible, then take another 3.0000±0.0002 g (anhydrous lithium tetraborate: lithium metaborate mixed flux = 12:22, baked at 750℃ for 2 h) of solid flux and spread it in a platinum crucible, then put the weighed sample, oxidant and internal standard on the solid flux spread in the platinum crucible, then take another 3.0000±0.0002 g (anhydrous lithium tetraborate: lithium metaborate mixed flux = 12:22, baked at 750℃ for 2 h h) The solid flux is covered on the test sample, oxidant and internal standard, and maintained at 750°C for 5 minutes. It should be noted here that the embedding method is adopted when feeding, and the sample does not need to be transferred, which reduces the random error of the experiment, improves the experimental accuracy, reduces the sample preparation time, avoids the loss of intermediate sample transfer, and can effectively avoid the damage of sulfide ore to the platinum crucible, extend the service life of the platinum crucible, and reduce the experimental cost; finally, a release agent is added to the platinum crucible. The release agent is a lithium bromide or ammonium bromide solution with a mass percentage of 30%-40%. The amount of release agent added should ensure that the sample has good fluidity and is easy to demold, about 0.50mL, and the melting procedure is carried out at 1050°C according to pre-melting for 120s-shaking for 600s-standing for 60s.

[0058] Matrix effect correction: The preparation of test samples by the melting method is to dilute the sample to make a glass sample, which can reduce the mineral effect and particle size effect of the sample. However, after the components of the test material are excited by X-ray fluorescence, there are still absorption effects and enhancement effects between each other, and the matrix effect cannot be ignored. The matrix effect including the fluorescence intensity ratio of molybdenum and niobium is automatically corrected using formula (1):

[0059] ω Mo =[I Mo / I Nb ×A0+A1] / M Mo ×100% (1)

[0060] Where: ω Mo - Corrected Mo content;

[0061] I Mo - Fluorescence intensity of Mo in the sample, Kcps;

[0062] I Nb - Fluorescence intensity of Nb in the sample, Kcps;

[0063] A0 - slope of the calibration curve;

[0064] A1 - intercept of the calibration curve;

[0065] M Mo - Test sample weight, g.

[0066] <Standard working curve drawing>

[0067] Take 15 standard samples, the molybdenum content of the standard samples ranges from 20.00 to 60.00%, covering the range of molybdenum concentrate products. After preparing the standard samples according to the preparation steps of the test samples, the fluorescence intensity is measured on a wavelength dispersive spectrometer according to the conditions in Table 1, and the fluorescence intensity of molybdenum and niobium elements (I Mo and I Nb The results are listed in Table 2, and the ordinate y is the molybdenum content in the sample, and the fluorescence intensity ratio of molybdenum and niobium elements (I Mo / I Nb ) is the horizontal coordinate x, and the working curve is obtained, such as Figure 3 shown.

[0068] The relationship between the fluorescence intensity value and the mass fraction of molybdenum in the sample was calculated using a mathematical model (least square fitting), and the final result was formula (2):

[0069] y=47.84498x-5.56943 (2)

[0070] Where: x is the fluorescence intensity measured by the instrument, and y is the calculated molybdenum amount.

[0071] Working curve correlation coefficient R 2 =0.99997, E 斜率 =47.84498, B 截距 =-5.56943. The above parameters show that when the molybdenum content in the sample is in the range of 20.00-60.00%, the linear relationship between the fluorescence intensity ratio of molybdenum and niobium and the mass fraction of molybdenum is good. According to this linear curve, the fitted molybdenum content M 1Mo (The fluorescence intensity of molybdenum and niobium is measured and substituted into the fitting formula to calculate. The instrument comes with a fitting tool that directly gives the calculation result), thus obtaining the absolute error |M Mo -M 1Mo ∣, and then determine whether a good working curve can be obtained by using niobium as the internal standard. The specific results are shown in Table 2.

[0072] Table 2 Measurement information of standard samples

[0073]

[0074] <Precision Experiment of the Present Invention>

[0075] According to the preparation conditions of the test samples, 11 verification samples were prepared for the national standard sample GBW07144, and the I was measured according to the selected final test conditions. Mo and INb Get the fluorescence intensity I Mo / I Nb , the mass fraction of molybdenum in the standard sample M is calculated according to formula (2): 1Mo , thus obtaining the average value, standard deviation, relative standard deviation and absolute error of the actual measured value of the standard sample. The marked value of the national standard sample is 50.08%. The specific verification is shown in Table 3.

[0076] Table 3 Precision experiment of the method for determining molybdenum with niobium internal standard (n=11)

[0077]

[0078] The precision experimental results in Table 3 show that the RSD of molybdenum in 11 parallel samples is 0.204%, and the absolute error is between 0.02% and 0.22%. In summary, the niobium internal standard method for determining the amount of molybdenum in molybdenum concentrate performs well in controlling experimental influencing factors and has good method precision.

[0079] <Measurement of sample to be tested>

[0080] Within the detection range, 15 products with large differences in molybdenum content in molybdenum concentrate samples from different mines were selected. The molybdenum content was determined by this method and compared with the results of the current industry standard YS / T 555.1 method. The results are listed in Table 4.

[0081] Table 4 Determination of samples to be tested

[0082]

[0083] The determination information of the samples in Table 4 shows that the error between the molybdenum content determined by this method and the YS / T 555.1 method is between 0.01 and 0.30%. Therefore, this method can be used to accurately determine the molybdenum content of molybdenum concentrate products.

[0084] The above is an explanation of the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for quantitatively detecting the amount of molybdenum in molybdenum concentrate using niobium internal standard X-ray fluorescence spectrometry, characterized in that: The steps include: (1) Preparation of test standard samples: According to the YS / T 555.1 method, the internal control sample of molybdenum concentrate is determined. After drying, multiple internal control samples of different concentrations are selected according to a certain concentration gradient. A certain amount of the internal control sample, solid flux, oxidant, release agent and internal standard are weighed respectively. First, part of the solid flux is spread in a platinum crucible, and the weighed internal control sample, oxidant and internal standard are added to the solid flux spread in the platinum crucible. Then, the remaining solid flux is used to cover the internal control sample, oxidant and internal standard. The temperature is kept at 750°C for 5 minutes. Finally, the release agent is dripped into the platinum crucible. The melting procedure is pre-melting at 1050°C for 120 seconds, shaking for 600 seconds, and standing for 60 seconds to prepare test standard samples respectively. (2) Establishing a test standard curve: The test standard samples prepared in step (1) are placed on a wavelength dispersive spectrometer to measure the fluorescence intensity, and the fluorescence ratio intensity of molybdenum and niobium elements is used as the horizontal axis, and the mass fraction of molybdenum in the corresponding standard sample determined according to the YS / T 555.1 method is used as the vertical axis to prepare a standard sample working curve; (3) Determination of the amount of molybdenum in molybdenum concentrate: Weigh a certain amount of molybdenum concentrate sample, solid flux, oxidant, release agent and internal standard, prepare the sample according to the preparation conditions of step (1), and then measure the fluorescence intensity ratio of molybdenum and niobium elements in the sample according to the test conditions of step (2). Calculate the amount of molybdenum in the molybdenum concentrate sample based on the working curve of the standard sample prepared in step (2).

2. The method for quantitatively detecting the amount of molybdenum in molybdenum concentrate by using niobium internal standard X-ray fluorescence spectrometry according to claim 1, characterized in that: The internal standard was niobium pentoxide.

3. The method for quantitatively detecting the amount of molybdenum in molybdenum concentrate by using niobium internal standard X-ray fluorescence spectrometry according to claim 2, characterized in that: The solid flux is a mixture of anhydrous lithium tetraborate and lithium metaborate in a mass ratio of 12:22, and the mass ratio of the solid flux to the sample is 12:

1.

4. The method for quantitatively detecting the amount of molybdenum in molybdenum concentrate by using niobium internal standard X-ray fluorescence spectrometry according to claim 2, characterized in that: The oxidant is solid lithium nitrate or a lithium nitrate solution with a mass fraction of 50%.

5. The method for quantitatively detecting the amount of molybdenum in molybdenum concentrate by using niobium internal standard X-ray fluorescence spectrometry according to claim 2, characterized in that: The release agent is a 30%-40% by mass ammonium bromide or lithium bromide solution.

6. The method for quantitatively detecting the amount of molybdenum in molybdenum concentrate by using niobium internal standard X-ray fluorescence spectrometry according to claim 2, characterized in that: The test conditions of step (2) are that the analytical line of molybdenum is Mo Lβ, and the internal standard line of niobium is Nb Lβ, wherein the wavelength range of Mo Lβ line is 0.4920-0.5177 nm, and the absorption limit is 0.4914 nm; the wavelength of Nb Lβ line is 0.5234-0.5491 nm, and the absorption limit is 0.5223 nm.

7. The method for quantitatively detecting the amount of molybdenum in molybdenum concentrate by using niobium internal standard X-ray fluorescence spectrometry according to claim 2, characterized in that: The mass fraction of molybdenum in the internal control samples ranges from 20.00% to 60.00%.

8. The method for quantitatively detecting the amount of molybdenum in molybdenum concentrate according to any one of claims 1 to 7, characterized in that: The matrix effect including the fluorescence intensity ratio of molybdenum and niobium is automatically corrected using formula (1): ω Mo =[I Mo / I Nb ×A0+A1] / M Mo ×100% (1) in: ω Mo - Corrected Mo content; I Mo - Fluorescence intensity of Mo in the sample, Kcps; I Nb - Fluorescence intensity of Nb in the sample, Kcps; A0 - slope of the calibration curve; A1 - intercept of the calibration curve; M Mo - Test sample weight, g.

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