Method for determining ratio of boron to gallium in silicate

Abstract

The invention relates to a method for measuring the boron-gallium ratio of silicate. The method comprises the following steps: (1) digesting a sample by using a hydrolyzed Na2O2 alkali fusion method and preparing a sample mother solution; (2) preparing a sample dilution solution and a sensitivity drift correction solution; (3) preparing a calibration curve standard solution by using a mixed solution of a hydrolyzed Na2O2 solution and nitric acid; and (4) carrying out plasma mass spectrometry test to obtain the boron-gallium ratio of the sample. According to the determination method, a mixed sample diluted solution is used as a sensitivity drift correction solution for instrument signal floating correction, and a standard solution matched with a sample diluted solution matrix is used for calibration, so that different matrix effects of boron and gallium caused by different media are avoided, and meanwhile, the problem of reagent background deduction is solved; therefore, the effect of efficiently and accurately testing the boron-gallium ratio is achieved.

Description

Technical Field

[0001] The invention relates to a method for determining the boron-gallium ratio of silicate, in particular to silicate with a 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 changes in salinity of water bodies in different sedimentary environments during geological history than existing indicators such as Sr / Ba and S / TOC.

[0003] Usually, the gallium content needs to be dissolved by acid dissolution. The specific steps are: after mixing the sample powder with nitric acid + hydrofluoric acid in a digestion tank, heat it to about 120°C on a hot plate or a high-temperature and high-pressure digestion tank and keep it dissolved at high temperature for 24 to 72 hours. After evaporation to remove silicon and hydrofluoric acid in the sample, it is then evaporated at least three times with concentrated nitric acid and the medium is transferred to high temperature before it can be fixed to volume with dilute nitric acid. After ensuring that the sample dilution is greater than 1000, the gallium content can be obtained through the plasma mass spectrometer ICP-MS test. Before the mass spectrometry test, it is usually necessary to calibrate the sensitivity of the instrument with nitric acid and a standard solution of the element to be measured. Usually, solutions of target elements 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 the boron content of silicate, the sample can also be digested by acid dissolution, but the sample powder must be digested by adding mannitol and hydrogen peroxide at low temperature (55°C or lower). This is because boron that is not complexed with mannitol is easy to volatilize in an acidic environment, resulting in the problem of too low boron content. The sample needs to react with hydrofluoric acid for 15 days under constant temperature conditions. After that, the sample needs to be evaporated at a low temperature of 55°C and converted into a nitric acid medium before it can be diluted to a fixed volume and ICP-MS mass spectrometry test can be performed. In addition, a second organic reagent, ethylene glycol, needs to be added during the medium conversion process to inhibit the volatilization of boron. This sample dissolution method not only fails to remove the organic matter contained in the sample, but also requires the addition of a large amount of organic reagents during the sample digestion process. However, the use of ICP-MS to test solutions containing organic matter is likely to cause matrix effects (because organic matter and other matrices will cause different degrees of suppression or enhancement of the signal of the element to be measured), resulting in inaccurate test data. Therefore, the acid dissolution method is time-consuming to test the boron / gallium ratio of silicate samples, and it is easy to cause data errors due to the organic matter components in the sample solution.

[0005] The boron content in the sample can also be tested after digestion by alkali fusion. However, the existing method requires column chemical separation and purification after adding a diluent before the boron content can be accurately determined by a mass spectrometer. Although this method can obtain accurate boron and gallium contents, because the two need to weigh different sample powders and dissolve and measure them through different dissolution methods, they are easily interfered by the inhomogeneity of the sample itself, resulting in errors in the boron-gallium ratio.

[0006] The alkali fusion method can be used to digest the sample and test the boron and gallium contents at the same time to avoid the problems caused by sample heterogeneity. This method has the advantages of short time consumption, can effectively remove organic matter in the sample and avoid the matrix effect caused by organic matter in the sample solution. However, because the added solvent contains a large amount of cations (Na or K), these cations will also cause matrix effects on the elements to be measured, and alkaline solutions with too high solid concentrations will cause problems such as blocking of the injection cone, decreased test signals, and reduced accuracy. Therefore, the sample needs to be diluted more times to avoid serious matrix effects. However, the concentration of the target element in the overly diluted sample solution will also become lower, thus being closer to the minimum limit of the instrument test signal or the environmental background value, causing greater test errors. Secondly, because there is a large amount of silicon in the alkaline solution of silicate, when adding too concentrated or excessive acid for acidification, it is easy to cause the formation of silica gel, which brings difficulties to the sample introduction of mass spectrometry test. At the same time, if too little acid is added, Ga will not be able to dissolve in the sample mother solution to form free ions, resulting in the problem of small B / Ga measurement values. Finally, the traditional alkali fusion method has the problem of too high reagent background and difficulty in accurate deduction, which leads to inaccurate data.

[0007] At present, the methods for testing the boron-gallium ratio in the prior art 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 to pre-treat the boron and gallium contents; (3) dangerous chemical hydrofluoric acid is required to digest silicate samples; (4) to avoid 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 quantitative amount of Rh or In element is generally added to the sample dilution solution for instrument sensitivity floating correction, 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 deficiencies of the above-mentioned prior art and to provide an efficient and accurate method for determining the boron-gallium ratio of silicate, which 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.

[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) 10 to 100 mg of sample and 1 to 4 mL of hydrolyzed Na2O2 solution are thoroughly mixed in a silver crucible; wherein the density of the hydrolyzed Na2O2 solution at room temperature is 1.12 to 1.15 g / mL;

[0013] (1.2) The mixed solution in step (1.1) is evaporated to dryness on a hot plate at 60-80° C., and then the silver crucible is covered and placed in a muffle furnace, and melted at 710-730° C. for 15-20 min;

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

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

[0016] (1.5) Add 2-8 mL of 2M nitric acid to a centrifuge tube, and then add 6-36 mL of 3% dilute nitric acid. If there is still residual sample in the silver crucible, use some of the dilute nitric acid to continue dissolving. Then, mix all the solutions in a test tube to obtain 10-40 mL of a fixed volume sample mother solution, where 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) Take 0.5-1 mL of the sample mother solution, transfer it 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 of 2800-10000 times, of which the alkaline solution dilution is 80-200 times;

[0019] (2.2) Take out 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, which 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, thereby most effectively correcting the error caused by the fluctuation of instrument sensitivity 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 of step (3.1) to prepare matrix-matched calibration curve standard solutions containing 0 ug / g, 5 ug / g, 10 ug / g, 20 ug / g, and 50 ug / g of boron and gallium, respectively, and having the same alkaline 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 of each calibration curve standard solution;

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

[0026] (4.3) After using the boron and gallium calibration curve standard solutions to calibrate the correlation between the signal and the boron and gallium concentrations of the sample, test the sensitivity drift correction solution and correct the instrument sensitivity fluctuation through the signal change of the sensitivity drift correction solution;

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

[0028] (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 prepared in the same way as the sample through steps (1) to (2)), calculate the boron-gallium ratio of the sample.

[0029] As a preferred embodiment of the method for determining the silicate boron-gallium ratio of the present invention, in the 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 silicate boron-gallium ratio of the present invention, in the 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 the 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, the 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 silicate boron-gallium ratio provided by the present invention can achieve at least one of the following beneficial effects:

[0035] (1) The present invention uses a hydrolyzed Na2O2 solution to completely digest 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 by 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 dissolves and transfers the residual alkali melt with 2-3% dilute nitric acid at room temperature, and then adds 2M nitric acid twice the volume of the alkali solution into the test tube to neutralize the alkali solution, which 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) Mix 50 mg of GSJ-JB-2 sample and 2 mL of hydrolyzed Na2O2 solution (density 1.13 g / mL at room temperature) in a silver crucible;

[0043] (1.2) The mixed solution in step (1.1) was evaporated to dryness on a hot plate at 60°C, and then the silver crucible was covered and placed in a muffle furnace and melted at 710°C for 20 min;

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

[0046] (1.5) Add 4 mL of 2 M nitric acid to a centrifuge tube, then add 11 mL of 2% dilute nitric acid, mix thoroughly to obtain 20 mL of sample stock solution, the sample dilution is 400 times, and the alkaline solution dilution is 10 times;

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

[0048] (2.1) Take 0.5 mL of the sample mother solution, transfer it to a 15 mL centrifuge tube, add 4.5 mL of 2% dilute nitric acid solution and mix thoroughly to obtain a sample dilution solution with a dilution ratio of 4000 times, of which the dilution ratio of the alkaline solution is 100 times;

[0049] (2.2) Take out 0.5 mL of each sample dilution solution and mix it in a new 50 mL centrifuge tube to obtain a sensitivity drift correction solution, which 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, thereby most effectively correcting the errors caused by the fluctuation of instrument sensitivity 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) Add 8 mL of 2M nitric acid and 28 mL of 3% dilute nitric acid to 4 mL of hydrolyzed Na2O2 solution to prepare a mother solution;

[0052] (3.2) using the mother solution prepared in step (3.1) to prepare calibration curve standard solutions containing 0ug / g, 5ug / g, 10ug / g, 20ug / g, and 50ug / g of boron and gallium, respectively, which match the matrix of the diluted sample solution;

[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 of each calibration curve standard solution;

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

[0056] (4.3) After using the boron and gallium calibration curve standard solutions to calibrate the correlation between the signal and the boron and gallium concentrations of the sample, test the sensitivity drift correction solution and correct the instrument sensitivity fluctuation through the signal change of the sensitivity drift correction solution;

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

[0058] (4.5) After correcting the instrument sensitivity fluctuation and deducting the background (the background is prepared by diluting the silver crucible and hydrolyzed Na2O2 solution in the same way 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 value published 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) Mix 40 mg of sample and 2 mL of hydrolyzed Na2O2 solution (density 1.14 g / mL at room temperature) in a silver crucible;

[0063] (1.2) The mixed solution in step (1.1) was evaporated to dryness on a hot plate at 80°C, and then the silver crucible was covered and placed in a muffle furnace and melted at 730°C for 15 min;

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

[0066] (1.5) Add 4 mL of 2 M nitric acid to a centrifuge tube, then add 32 mL of 3% dilute nitric acid, mix thoroughly to obtain 40 mL of sample stock solution, the sample dilution is 1000 times, and the alkaline solution dilution is 20 times;

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

[0068] (2.1) Take 1 mL of the sample mother solution, transfer it 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 a sample dilution ratio of 8000 times, of which the alkaline solution dilution ratio is 160 times;

[0069] (2.2) Take out 0.5 mL of each sample dilution solution and mix it in a new 50 mL centrifuge tube to obtain a sensitivity drift correction solution, which 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, thereby most effectively correcting the errors caused by the fluctuation of instrument sensitivity 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) Add 4 mL of 2M nitric acid and 14 mL of 3% dilute nitric acid to 2 mL of hydrolyzed Na2O2 solution to prepare an alkaline solution with a dilution of 10 times;

[0072] (3.2) using the mother solution prepared in step (3.1) to prepare calibration curve standard solutions containing 0ug / g, 5ug / g, 10ug / g, 20ug / g, and 50ug / g of boron and gallium, respectively, which match the matrix of the diluted sample solution;

[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 of each calibration curve standard solution;

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

[0076] (4.3) After using the boron and gallium calibration curve standard solutions to calibrate the correlation between the signal and the boron and gallium concentrations of the sample, test the sensitivity drift correction solution and correct the instrument sensitivity fluctuation through the signal change of the sensitivity drift correction solution;

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

[0078] (4.5) After correcting the instrument sensitivity fluctuation and deducting the background (the background is prepared by diluting the silver crucible and the hydrolyzed Na2O2 solution in the same way 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 existing 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 is too small (2M acid: hydrolyzed Na2O2 solution volume ratio = 1:1).

[0082] In the comparative example step (1.5), the volume ratio of 2M nitric acid to 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 larger than the literature value of 9.07±1.81 (2SD, N=132).

[0083] Comparative Example 2: The acid-base ratio is 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 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 no 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. The following data were obtained after machine testing: 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 the steps (1.3)-(1.5) of the comparative example, water was not first added to heat and dissolve the alkali melt, and then dilute acid was added to dissolve the residue at room temperature. Instead, 4 mL of 2M hydrochloric acid was directly added to dissolve the alkali melt at room temperature (the volume ratio of 2M acid: hydrolyzed Na2O2 solution was 2:1). Apart from this, the remaining steps and parameters were the same as those of Example 2. Direct addition of 2M acid resulted in the volatilization of boron, and the following data were obtained after testing on the machine: the test value of the GSJ-JR-2 standard sample was B / Ga=6.12, which was too small compared to the literature range value 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) digesting the sample by hydrolyzing Na2O2 alkali fusion method and gradually dissolving the alkali fusion by water and dilute nitric acid to prepare a sample mother solution; (2) preparing sample dilution solution and sensitivity drift correction solution; (3) Prepare the calibration curve standard solution by using a mixture of hydrolyzed Na2O2 solution and nitric acid solution; (4) Conduct plasma mass spectrometry testing to obtain the boron-gallium ratio of the sample.

2. The method for determining the silicate boron-gallium ratio according to claim 1, characterized in that: The step (1) specifically comprises the following steps: (1.1) Mix 10-100 mg of sample and 1-4 mL of hydrolyzed Na2O2 solution in a silver crucible; (1.2) After the uniformly mixed solution in step (1.1) is evaporated to dryness at 60-80° C., the silver crucible is covered and placed in a muffle furnace, and melted at 710-730° C. for 15-20 min; (1.3) After cooling, add 1-4 mL of boron-free deionized water into a silver crucible and heat at 60°C for 20-30 min to dissolve most of the sample, and then transfer to a centrifuge tube; (1.4) At room temperature, add 1 to 4 mL of 2% to 3% dilute nitric acid solution to a silver crucible to dissolve the residual sample on the inner wall of the silver crucible, and transfer the solution to the centrifuge tube in step (1.3); (1.5) Add 2-8 mL of 2M nitric acid to a centrifuge tube, and then add 6-36 mL of 3% dilute nitric acid. If there is still residual sample in the silver crucible, use some of the dilute nitric acid to continue dissolving it. Then mix all the solutions in a test tube to obtain 10-40 mL of a fixed volume of sample mother solution, where the sample dilution is 400-2000 times and the alkaline solution dilution is 10-20 times.

3. The method for determining the silicate boron-gallium ratio according to claim 2, characterized in that: In the step (1.5), the volume ratio of 2M nitric acid to the hydrolyzed Na2O2 solution is 2:

1.

4. The method for determining the silicate boron-gallium ratio according to claim 1, characterized in that: The step (2) specifically comprises the following steps: (2.1) Take 0.5-1 mL of the sample mother solution, transfer it 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, wherein the dilution ratio of the alkaline solution 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.

5. The method for determining the silicate boron-gallium ratio according to claim 4, characterized in that: In the step (2.2), the volume of the equal volume solution is 0.5-1 mL.

6. The method for determining the silicate boron-gallium ratio according to claim 1, characterized in that: The step (3) specifically comprises 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 a calibration curve standard solution containing 0ug / g, 5ug / g, 10ug / g, 20ug / g, and 50ug / g of boron and gallium, respectively, and matching the matrix with the alkaline concentration of the diluted sample solution.

7. The method for determining the silicate boron-gallium ratio according to claim 6, characterized in that: In the step (3.1), the volume ratio of 2M nitric acid to the hydrolyzed Na2O2 solution is 2:

1.

8. The method for determining the silicate boron-gallium ratio according to claim 1, characterized in that: The step (4) specifically comprises the following steps: (4.1) testing each calibration curve standard solution by plasma mass spectrometry to obtain boron and gallium signals of each calibration curve standard solution; (4.2) Calculate the linear relationship between the signal obtained from each calibration curve standard solution test 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 the instrument sensitivity fluctuation and subtracting the background, which is prepared by diluting the silver crucible and the hydrolyzed Na2O2 solution in the same way as the sample through steps (1) to (2), the boron-gallium ratio of the sample is calculated.

9. The method for determining the silicate boron-gallium ratio according to claim 8, characterized in that: Test the sensitivity drift correction solution every time 5 to 10 sample dilution solutions are tested.

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

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