A method for determining the ratio of boron to gallium in silicates

Abstract

The present invention relates to a method for determining the boron-gallium ratio of silicates, comprising the following steps: (1) digesting a sample using a hydrolyzed Na2O2 alkali fusion method to prepare a sample mother solution; (2) preparing a sample dilution solution and a sensitivity drift correction solution; (3) preparing a calibration curve standard solution using a hydrolyzed Na2O2 solution and a nitric acid mixed solution; and (4) performing a plasma mass spectrometry test to obtain the boron-gallium ratio of the sample. The determination method of the present invention uses the mixed sample dilution solution as a sensitivity drift correction solution to perform instrument signal float correction, and a standard solution matching the matrix of the sample dilution solution for calibration, thereby avoiding the different matrix effects of boron and gallium caused by different media and solving the problem of reagent background subtraction, thereby achieving the effect of efficiently and accurately testing the boron-gallium ratio.

Description

Technical Field

[0001] The present invention relates to a method for determining the boron-gallium ratio of silicates, in particular for silicates with high organic matter content (such as shale), and belongs to the technical field of boron and gallium element content analysis. Background Art

[0002] The boron-gallium ratio of sediments is an important alternative indicator for recording paleosalinity in geological research. It can more accurately indicate the salinity changes of water bodies in different sedimentary environments during geological history than existing indicators such as Sr / Ba and S / TOC.

[0003] Typically, the gallium content needs to be determined through acid dissolution. The specific steps are as follows: After mixing the sample powder with nitric acid and hydrofluoric acid in a digestion tank, heat it to about 120°C on a hot plate or in a high-temperature and high-pressure digestion tank and maintain the high-temperature dissolution for 24 to 72 hours. After evaporation to remove silicon and hydrofluoric acid from the sample, it is then evaporated at high temperature with concentrated nitric acid at least three times to dry the medium before it can be made up to volume with dilute nitric acid. Only after ensuring that the sample dilution is greater than 1000 can the gallium content be obtained through the plasma mass spectrometer ICP-MS test. Before mass spectrometry testing, it is usually necessary to calibrate the sensitivity of the instrument using nitric acid and a standard solution of the element to be measured. Usually, solutions of the target element with different contents such as 0μg / g, 1μg / g, 10μg / g, 20μg / g, and 50μg / g that match the sample solution are used.

[0004] When testing boron content in silicates, samples can also be digested using acid digestion, but the sample powder must be digested at low temperatures (55°C or lower) with mannitol and hydrogen peroxide. This is because boron uncomplexed with mannitol readily volatilizes in an acidic environment, resulting in an underestimation of the boron content. The sample must react with hydrofluoric acid for 15 days at a constant temperature. Afterward, the sample must be evaporated to dryness at 55°C and converted into nitric acid before dilution and ICP-MS analysis. Furthermore, a second organic reagent, ethylene glycol, must be added during the conversion process to suppress boron volatilization. This digestion method not only fails to remove organic matter from the sample but also requires the addition of a large amount of organic reagent during the sample digestion process. However, using ICP-MS to analyze solutions containing organic matter is prone to matrix effects (organic matter and other matrices can suppress or enhance the signal of the element being analyzed to varying degrees), leading to inaccurate test data. Therefore, determining the boron / gallium ratio of silicate samples using acid digestion is time-consuming and prone to data errors due to the presence of organic matter in the sample solution.

[0005] The boron content in a sample can also be determined by alkaline fusion digestion followed by testing. However, existing methods require the addition of a diluent followed by column chemical separation and purification before accurate determination of the boron content using a mass spectrometer. While this method can accurately determine the boron and gallium contents, because the two require weighing different sample powders and dissolving and measuring them using different dissolution methods, it is susceptible to interference from sample heterogeneity, leading to errors in the boron-gallium ratio.

[0006] Alkali fusion can be used to digest the sample and simultaneously measure the boron and gallium contents, thus avoiding the problems caused by sample inhomogeneity. This method is time-efficient, effectively removes organic matter from the sample, and avoids matrix effects caused by organic matter in the sample solution. However, because the added solvent contains a large amount of cations (Na or K), these cations can also cause matrix effects on the elements being measured. Furthermore, alkaline solutions with excessively high solids concentrations can cause injection cone blockage, signal degradation, and reduced accuracy. Therefore, the sample needs to be diluted several times to avoid severe matrix effects. However, an overly diluted sample solution also reduces the concentration of the target element, bringing it closer to the instrument's minimum test signal or ambient background value, resulting in greater measurement error. Furthermore, because alkaline solutions of silicates contain a large amount of silicon, the addition of overly concentrated or excessive acid for acidification can easily lead to the formation of silica gel, complicating sample introduction for mass spectrometry. Furthermore, if too little acid is added, Ga cannot dissolve in the sample mother solution to form free ions, resulting in a low B / Ga ratio. Finally, the traditional alkali fusion method has the problem of high reagent background and difficulty in accurate deduction, which leads to inaccurate data.

[0007] Currently, the methods for testing the boron-gallium ratio in the existing technology have the following problems: (1) low efficiency, requiring 15 to 30 days to digest a batch of samples; (2) different sample digestion methods are required for sample pretreatment to determine the boron and gallium contents; (3) hazardous chemical hydrofluoric acid is required to digest silicate samples; (4) to prevent boron volatilization, multiple organic reagents need to be added, and the organic matter contained in the sample itself cannot be removed, which may lead to inaccurate ICP-MS testing; (5) a certain amount of Rh or In element is generally added to the sample dilution solution to correct the instrument sensitivity fluctuation, but Rh or In has different test sensitivities from boron and gallium during the mass spectrometer test. Therefore, it is very necessary to develop an efficient and accurate method for testing the boron-gallium ratio of silicates. Summary of the Invention

[0008] The object of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a method for determining the boron-gallium ratio of silicate in an efficient and accurate manner. This method avoids the different matrix effects of boron and gallium caused by different media, and at the same time solves the problem of reagent background subtraction, thereby achieving the effect of efficiently and accurately testing the boron-gallium ratio.

[0009] To achieve the above object, the technical solution adopted by the present invention is:

[0010] A method for determining the boron-gallium ratio of silicate comprises the following steps:

[0011] (1) Digest the sample with hydrolyzed Na2O2 alkali fusion method and prepare the sample mother solution:

[0012] (1.1) Thoroughly mix 10–100 mg of sample with 1–4 mL of a hydrolyzed Na₂O₂ solution in a silver crucible. The hydrolyzed Na₂O₂ solution has a density of 1.12–1.15 g / mL at room temperature.

[0013] (1.2) Evaporate the mixed solution obtained in step (1.1) on a hot plate at 60-80°C to dryness, then cover the silver crucible and place it in a muffle furnace, melting it at 710-730°C for 15-20 minutes.

[0014] (1.3) After cooling, add 1–4 mL of boron-free deionized water to a silver crucible and heat at 60°C for 20–30 min to dissolve most of the sample. Transfer the sample to a 50 mL centrifuge tube.

[0015] (1.4) At room temperature, add 1-4 mL of 2%-3% dilute nitric acid solution to a silver crucible to dissolve the residual sample on the inner wall of the silver crucible. Transfer this solution to the centrifuge tube in step (1.3);

[0016] (1.5) Add 2–8 mL of 2 M nitric acid to the centrifuge tube, followed by 6–36 mL of 3% dilute nitric acid. If any sample residue remains in the silver crucible, use some of the dilute nitric acid to dissolve the remaining sample. Thoroughly mix all the solutions in the test tube to obtain a 10–40 mL sample solution. The sample dilution is 400–2000 times, and the alkaline solution dilution is 10–20 times.

[0017] (2) Prepare sample dilution solution and sensitivity drift correction solution:

[0018] (2.1) Transfer 0.5-1 mL of the sample stock solution to a 15 mL centrifuge tube. Add 3.5-9 mL (or 7-9 times) of 2-3% dilute nitric acid solution and mix thoroughly to obtain a sample dilution solution with a sample dilution ratio of 2800-10000 times, of which the alkaline solution dilution ratio is 80-200 times.

[0019] (2.2) Take an equal volume of solution from each sample dilution solution and mix it in a new 50mL centrifuge tube to obtain a sensitivity drift correction solution with the same dilution as the sample dilution solution. This solution is used to correct the fluctuation of instrument sensitivity. This method can ensure that the sensitivity drift correction solution can represent the average composition of the sample, thus most effectively correcting the error caused by instrument sensitivity fluctuation during the test of different target elements.

[0020] (3) Prepare the calibration curve standard solution using a mixture of hydrolyzed Na2O2 solution and nitric acid solution:

[0021] (3.1) Add 4-8 mL of 2M nitric acid and 14-28 mL of 2% to 3% dilute nitric acid to 2-4 mL of hydrolyzed Na2O2 solution;

[0022] (3.2) Using the mother solution from step (3.1), prepare matrix-matched calibration curve standard solutions containing 0 μg / g, 5 μg / g, 10 μg / g, 20 μg / g, and 50 μg / g of boron and gallium, respectively, and having the same base concentration as the diluted sample solution;

[0023] (4) Perform plasma mass spectrometry to obtain the boron-gallium ratio of the sample:

[0024] (4.1) Testing each calibration curve standard solution by plasma mass spectrometry to obtain boron and gallium signals for each calibration curve standard solution;

[0025] (4.2) Calculate the linear relationship between the signal obtained from each calibration curve standard solution and its boron and gallium concentration, and use this linear relationship to convert the signal obtained from the sample solution test into the boron and gallium concentration;

[0026] (4.3) After calibrating the correlation between the signal and the boron and gallium concentrations of the sample using the boron and gallium calibration curve standard solutions, test the sensitivity drift correction solution. The sensitivity drift correction solution is used to correct the instrument sensitivity fluctuation.

[0027] (4.4) Boron and gallium signals of the test sample dilution solution;

[0028] (4.5) After correcting for instrument sensitivity fluctuations and subtracting the background (the background is prepared by diluting the silver crucible and hydrolyzed Na2O2 solution prepared in the same manner as the sample through steps (1) to (2)), calculate the sample boron-gallium ratio.

[0029] As a preferred embodiment of the method for determining the silicate boron-gallium ratio of the present invention, in step (1.5), the volume ratio of 2M nitric acid to the hydrolyzed Na2O2 solution is 2:1.

[0030] As a preferred embodiment of the method for determining the boron-gallium ratio of silicate according to the present invention, in step (2.2), the volume of the equal volume solution is 0.5-1 mL.

[0031] As a preferred embodiment of the method for determining the silicate boron-gallium ratio of the present invention, in step (3.1), the volume ratio of 2M nitric acid to the hydrolyzed Na2O2 solution is 2:1.

[0032] As a preferred embodiment of the method for determining the silicate boron-gallium ratio of the present invention, a sensitivity drift correction solution is tested every time 5 to 10 sample dilution solutions are tested.

[0033] As a preferred embodiment of the method for determining the silicate boron-gallium ratio of the present invention, the sensitivity drift correction solution is tested after the sample dilution solution test is completed.

[0034] Compared with the prior art, the method for determining the boron-gallium ratio of silicate provided by the present invention can achieve at least one of the following beneficial effects:

[0035] (1) The present invention utilizes a hydrolyzed Na2O2 solution to completely dissolve the silicate sample powder, and then gradually adds relatively diluted (2M or more diluted) nitric acid to achieve the purpose of completely dissolving the sample. Finally, by using nitric acid and Na2O2 solution to prepare a calibration curve standard solution that matches the matrix of the diluted sample solution to be tested, and using the mixed sample dilution solution as a sensitivity drift correction solution to perform instrument signal floating correction, this method avoids the different matrix effects of boron and gallium caused by different media, and solves the problem of reagent background subtraction, thereby achieving the effect of efficiently and accurately testing the boron-gallium ratio.

[0036] (2) The present invention can complete the digestion and testing of a batch of samples within 24 to 48 hours, thereby improving the measurement efficiency; the present invention increases the accuracy of boron-gallium ratio analysis by digesting and testing the contents of two elements in the same sample powder; the present invention avoids the use of dangerous chemicals such as hydrofluoric acid; the present invention corrects the sensitivity drift of the instrument by repeatedly testing a sensitivity drift correction solution prepared with a mixed sample dilution solution that matches the dilution sample solution matrix, thereby improving the accuracy of the test.

[0037] (3) The present invention adopts a method of adding water to a silver crucible and heating at low temperature to dissolve most of the alkali melt and transfer it to a test tube, then dissolving and transferring the residual alkali melt with 2-3% dilute nitric acid at room temperature, and then adding 2M nitric acid twice the volume of the alkali solution to the test tube to neutralize the alkali solution. This method effectively avoids damage to the silver crucible, volatilization of boron, and formation of silica gel in the sample, thereby ensuring the stability of the sample mother solution. DETAILED DESCRIPTION

[0038] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below with reference to specific embodiments.

[0039] Example 1

[0040] A method for determining the boron-gallium ratio of silicate comprises the following steps:

[0041] (1) Digest the sample with hydrolyzed Na2O2 alkali fusion method and prepare the sample mother solution:

[0042] (1.1) Thoroughly mix 50 mg of GSJ-JB-2 sample with 2 mL of hydrolyzed Na2O2 solution (density 1.13 g / mL at room temperature) in a silver crucible;

[0043] (1.2) Evaporate the mixed solution obtained in step (1.1) on a hot plate at 60°C until dry, then place the covered silver crucible in a muffle furnace and melt at 710°C for 20 min.

[0044] (1.3) After cooling, add 3 mL of boron-free deionized water to a silver crucible and heat at 60°C for 30 min to dissolve most of the sample. Then transfer the sample to a 50 mL centrifuge tube.

[0045] (1.4) At room temperature, add 2 mL of 2% dilute nitric acid solution to a silver crucible to dissolve the residual sample on the inner wall of the silver crucible. Transfer this solution to the centrifuge tube in step (1.3);

[0046] (1.5) Add 4 mL of 2 M nitric acid to a centrifuge tube, followed by 11 mL of 2% dilute nitric acid. Mix thoroughly to obtain a 20 mL sample solution. The sample is diluted 400-fold, and the alkaline solution is diluted 10-fold.

[0047] (2) Prepare sample dilution solution and sensitivity drift correction solution:

[0048] (2.1) Transfer 0.5 mL of the sample stock solution to a 15 mL centrifuge tube. Add 4.5 mL of 2% dilute nitric acid solution and mix thoroughly to obtain a 4000-fold dilution of the sample solution, of which the alkaline solution dilution is 100-fold.

[0049] (2.2) Take 0.5 mL of each sample dilution solution and mix it in a new 50 mL centrifuge tube to prepare a sensitivity drift correction solution, which is used to correct for fluctuations in instrument sensitivity. This method ensures that the sensitivity drift correction solution represents the average composition of the sample, thereby most effectively correcting errors caused by instrument sensitivity fluctuations during the test of different target elements.

[0050] (3) Prepare the calibration curve standard solution using a mixture of hydrolyzed Na2O2 solution and nitric acid solution:

[0051] (3.1) Prepare a mother solution by adding 8 mL of 2M nitric acid and 28 mL of 3% dilute nitric acid to 4 mL of hydrolyzed Na2O2 solution.

[0052] (3.2) Using the mother solution prepared in step (3.1), prepare calibration curve standard solutions containing 0 μg / g, 5 μg / g, 10 μg / g, 20 μg / g, and 50 μg / g of boron and gallium, respectively;

[0053] (4) Perform plasma mass spectrometry to obtain the boron-gallium ratio of the sample:

[0054] (4.1) Testing each calibration curve standard solution by plasma mass spectrometry to obtain boron and gallium signals for each calibration curve standard solution;

[0055] (4.2) Calculate the linear relationship between the signal obtained from each calibration curve standard solution and its boron and gallium concentration, and use this linear relationship to convert the signal obtained from the sample solution test into the boron and gallium concentration;

[0056] (4.3) After calibrating the correlation between the signal and the boron and gallium concentrations of the sample using the boron and gallium calibration curve standard solutions, test the sensitivity drift correction solution. The sensitivity drift correction solution is used to correct the instrument sensitivity fluctuation.

[0057] (4.4) Test the boron and gallium signals of the sample dilution solution; test the sensitivity drift correction solution every 5 to 10 sample dilution solutions tested; test the sensitivity drift correction solution after the sample dilution solution test is completed;

[0058] (4.5) After correcting for instrument sensitivity fluctuations and subtracting the background (the background was prepared by diluting the silver crucible and hydrolyzed Na2O2 solution prepared in the same manner as the sample through steps (1) to (2)), the boron-gallium ratio of the sample was calculated and the following data were obtained: GSJ-JB-2B / Ga = 1.96 ± 0.28 (2SD, RSD 7%, N = 3); compared with the literature value of 1.78 ± 0.36 (2SD, RSD 10%, N = 713), it is consistent with the published value in the literature within the error range and has better accuracy than the literature.

[0059] Example 2

[0060] A method for determining the boron-gallium ratio of silicate comprises the following steps:

[0061] (1) Digest the sample with hydrolyzed Na2O2 alkali fusion method and prepare the sample mother solution:

[0062] (1.1) Thoroughly mix 40 mg of sample with 2 mL of hydrolyzed Na2O2 solution (density 1.14 g / mL at room temperature) in a silver crucible.

[0063] (1.2) Evaporate the mixed solution obtained in step (1.1) on a hot plate at 80°C until dry, then cover the silver crucible and place it in a muffle furnace, melting at 730°C for 15 min.

[0064] (1.3) After cooling, add 2 mL of boron-free deionized water to a silver crucible and heat at 60°C for 30 min to dissolve most of the sample. Then transfer the sample to a 50 mL centrifuge tube.

[0065] (1.4) At room temperature, add 2 mL of 3% dilute nitric acid solution to a silver crucible to dissolve the residual sample on the inner wall of the silver crucible. Transfer this solution to the centrifuge tube in step (1.3);

[0066] (1.5) Add 4 mL of 2 M nitric acid to a centrifuge tube, followed by 32 mL of 3% dilute nitric acid. Mix thoroughly to obtain 40 mL of sample solution. The sample dilution is 1000-fold, and the alkaline solution dilution is 20-fold.

[0067] (2) Prepare sample dilution solution and sensitivity drift correction solution:

[0068] (2.1) Transfer 1 mL of the sample stock solution to a 15 mL centrifuge tube. Add 7 mL of 3% dilute nitric acid solution and mix thoroughly to obtain a sample dilution solution with an 8000-fold dilution ratio, including a 160-fold dilution ratio of the alkaline solution.

[0069] (2.2) Take 0.5 mL of each sample dilution solution and mix it in a new 50 mL centrifuge tube to prepare a sensitivity drift correction solution, which is used to correct for fluctuations in instrument sensitivity. This method ensures that the sensitivity drift correction solution represents the average composition of the sample, thereby most effectively correcting errors caused by instrument sensitivity fluctuations during the test of different target elements.

[0070] (3) Prepare the calibration curve standard solution using a mixture of hydrolyzed Na2O2 solution and nitric acid solution:

[0071] (3.1) Prepare a 10-fold dilution of the alkaline solution by adding 4 mL of 2M nitric acid and 14 mL of 3% dilute nitric acid to 2 mL of the hydrolyzed Na2O2 solution.

[0072] (3.2) Using the mother solution prepared in step (3.1), prepare calibration curve standard solutions containing 0 μg / g, 5 μg / g, 10 μg / g, 20 μg / g, and 50 μg / g of boron and gallium, respectively;

[0073] (4) Perform plasma mass spectrometry to obtain the boron-gallium ratio of the sample:

[0074] (4.1) Testing each calibration curve standard solution by plasma mass spectrometry to obtain boron and gallium signals for each calibration curve standard solution;

[0075] (4.2) Calculate the linear relationship between the signal obtained from each calibration curve standard solution and its boron and gallium concentration, and use this linear relationship to convert the signal obtained from the sample solution test into the boron and gallium concentration;

[0076] (4.3) After calibrating the correlation between the signal and the boron and gallium concentrations of the sample using the boron and gallium calibration curve standard solutions, test the sensitivity drift correction solution. The sensitivity drift correction solution is used to correct the instrument sensitivity fluctuation.

[0077] (4.4) Test the boron and gallium signals of the sample dilution solution; test the sensitivity drift correction solution every 5 to 10 sample dilution solutions tested; test the sensitivity drift correction solution after the sample dilution solution test is completed;

[0078] (4.5) After correcting for instrument sensitivity fluctuations and deducting the background (the background is prepared by diluting the silver crucible and hydrolyzed Na2O2 solution in the same manner as the sample through steps (1) to (2)), the boron-gallium ratio of the sample is calculated, and the data obtained are shown in Table 1. Compared with the boron-gallium ratio calculated from the boron and gallium contents reported in the literature, the boron-gallium ratio of the standard substance measured by the present invention is not only consistent with the value published in the literature within the error range (indicating accuracy), but also has improved precision (RSD is not higher than 5%).

[0079] Table 1

[0080]

[0081] Comparative Example 1: The acid-base ratio was too small (2M acid: hydrolyzed Na2O2 solution volume ratio = 1:1).

[0082] In step (1.5) of this comparative example, the volume ratio of 2M nitric acid to the hydrolyzed Na2O2 solution is 1:1. Except for the above volume ratio, the remaining steps and parameters are the same as those in Example 2, and the following data are obtained: GSJ-JR-2 standard sample B / Ga=301.49, which is much larger than the literature value of 9.07±1.81 (2SD, N=132).

[0083] Comparative Example 2: The acid-base ratio was too small (2M acid: hydrolyzed Na2O2 solution volume ratio = 7:4).

[0084] In the comparative example step (1.5), the volume ratio of 2M nitric acid to the hydrolyzed Na2O2 solution is 7:4. Except for the above volume ratio, the remaining steps and parameters are the same as those in Example 1, and the following data are obtained: the Ga content of the GSJ-JB-2 standard sample is lower than the test range, and the B / Ga ratio cannot be obtained. The literature value is 1.78±0.36 (2SD, N=713); GSJ-JR-2B / Ga=85.46, which is too large compared to the literature range value of 9.07±1.81 (2SD, N=132) because Ga is not completely dissolved.

[0085] Comparative Example 3: No matrix-matched calibration curve standard solution and sensitivity drift correction solution were used.

[0086] In steps (3)-(4) of this comparative example, no matrix-matched calibration curve standard solution and sensitivity drift correction solution were used. Apart from this, the remaining steps and parameters were the same as those in Example 2. After testing on the machine, the following data were obtained: GSJ-JR-2 standard sample B / Ga=6.48-6.61, which is lower than the published value of 9.07±1.81 (2SD, N=132).

[0087] Comparative Example 4: Directly dissolving the alkali melt with 2M acid resulted in boron loss.

[0088] In steps (1.3)-(1.5) of this comparative example, instead of first adding water to dissolve the alkali melt by heating and then adding dilute acid to dissolve the residue at room temperature, 4 mL of 2M hydrochloric acid was directly added to dissolve the alkali melt at room temperature (the volume ratio of 2M acid to hydrolyzed Na₂O₂ solution was 2:1). Otherwise, the remaining steps and parameters were the same as in Example 2. Direct addition of 2M acid resulted in volatilization of boron. Testing on an instrument yielded the following data: the GSJ-JR-2 standard sample had a B / Ga ratio of 6.12, which is significantly lower than the literature range of 9.07±1.81 (2SD, N=132).

Claims

1. A method for determining the boron-gallium ratio of silicate, characterized in that: The steps include: (1) The sample was digested by hydrolyzing Na2O2 alkali fusion method and the alkali fusion was gradually dissolved with water and dilute nitric acid to prepare the sample mother solution; (2) Prepare sample dilution solution and sensitivity drift correction solution; (3) Prepare the calibration curve standard solution by hydrolyzing Na2O2 solution and nitric acid mixed solution; (4) performing plasma mass spectrometry to obtain the boron-gallium ratio of the sample; The step (1) specifically includes the following steps: (1.1) Thoroughly mix 10-100 mg of sample with 1-4 mL of hydrolyzed Na2O2 solution in a silver crucible; (1.2) Evaporate the mixed solution obtained in step (1.1) at 60-80°C to dryness, then cover the silver crucible and place it in a muffle furnace, melting it at 710-730°C for 15-20 minutes; (1.3) After cooling, add 1–4 mL of boron-free deionized water to a silver crucible and heat at 60°C for 20–30 min to dissolve most of the sample. Transfer the sample to a centrifuge tube. (1.4) At room temperature, add 1-4 mL of 2%-3% dilute nitric acid solution to a silver crucible to dissolve the residual sample on the inner wall of the silver crucible. Transfer this solution to the centrifuge tube in step (1.3); (1.5) Add 2–8 mL of 2 M nitric acid to the centrifuge tube, followed by 6–36 mL of 3% dilute nitric acid. If any sample remains in the silver crucible, use some of the dilute nitric acid to dissolve the remaining sample. Thoroughly mix all the solutions in the test tube to obtain a 10–40 mL sample solution. The sample is diluted 400–2000 times, and the alkaline solution is diluted 10–20 times. In the step (1.5), the volume ratio of 2M nitric acid to the hydrolyzed Na2O2 solution is 2:

1.

2. The method for determining the silicate boron-gallium ratio according to claim 1, wherein: The step (2) specifically includes the following steps: (2.1) Transfer 0.5-1 mL of the sample stock solution to a 15 mL centrifuge tube. Add 3.5-9 mL of 2-3% dilute nitric acid solution and mix thoroughly to obtain a sample dilution solution with a sample dilution ratio of 2800-10000 times, of which the alkaline solution dilution ratio is 80-200 times. (2.2) Take out an equal volume of solution from each sample dilution solution and mix it in a new centrifuge tube to obtain a sensitivity drift correction solution with the same dilution as the sample dilution solution.

3. The method for determining the silicate boron-gallium ratio according to claim 2, wherein: In the step (2.2), the volume of the equal volume solution is 0.5-1 mL.

4. The method for determining the silicate boron-gallium ratio according to claim 1, wherein: The step (3) specifically includes the following steps: (3.1) Add 4-8 mL of 2M nitric acid and 14-28 mL of 2% to 3% dilute nitric acid to 2-4 mL of hydrolyzed Na2O2 solution; (3.2) Use the mother solution of step (3.1) to prepare matrix-matched calibration curve standard solutions containing 0ug / g, 5ug / g, 10ug / g, 20ug / g, and 50ug / g of boron and gallium, respectively, and with the same alkaline concentration as the diluted sample solution.

5. The method for determining the silicate boron-gallium ratio according to claim 4, wherein: In the step (3.1), the volume ratio of 2M nitric acid to the hydrolyzed Na2O2 solution is 2:

1.

6. The method for determining the silicate boron-gallium ratio according to claim 1, wherein: The step (4) specifically includes the following steps: (4.1) Testing each calibration curve standard solution by plasma mass spectrometry to obtain boron and gallium signals for each calibration curve standard solution; (4.2) Calculate the linear relationship between the signal obtained from each calibration curve standard solution and its boron and gallium concentration; (4.3) Test sensitivity drift correction solution; (4.4) Boron and gallium signals of the test sample dilution solution; (4.5) After correcting for instrument sensitivity fluctuations and subtracting the background, which is prepared by diluting the silver crucible and hydrolyzed Na2O2 solution prepared in the same manner as the sample through steps (1) to (2), calculate the sample boron-gallium ratio.

7. The method for determining the silicate boron-gallium ratio according to claim 6, wherein: Test the sensitivity drift correction solution after every 5 to 10 sample dilution solutions.

8. The method for determining the silicate boron-gallium ratio according to claim 6, wherein: After the sample dilution solution test is completed, test the sensitivity drift correction solution.

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