A method for determining the content of tungsten and molybdenum in high-tungsten and low-molybdenum solutions using an energy dispersive X-ray fluorescence analyzer

Abstract

A method for determining the tungsten and molybdenum content in a high-tungsten and low-molybdenum solution by using an energy dispersive X-ray fluorescence analyzer, 1) preparing multiple standard samples for determining the WO3 curve; 2) using a colorimetric method to determine the WO3 and Mo values ​​of each sample in step 1); 3) preparing multiple standard samples for determining the Mo curve; 4) using a colorimetric method to determine the WO3 and Mo values ​​of each sample in step 3); 5) using an energy spectrometer to determine the working curve of WO3 in the high-tungsten and low-molybdenum solution; 6) using an energy spectrometer to determine the working curve of Mo in the high-tungsten and low-molybdenum solution; 7) a correction coefficient working curve; 8) determining the sample to be tested, obtaining the correction coefficient of the sample Mo and calculating the Mo content. The method solves the problem of inaccurate determination of the molybdenum content in the high-tungsten and low-molybdenum solution by an energy dispersive X-ray fluorescence analyzer, is simple to operate, has accurate measurement data, saves analysis time, and avoids environmental pollution.

Description

Technical field:

[0001] The invention relates to the field of X-ray fluorescence spectrum analysis, and mainly relates to a method for measuring the tungsten and molybdenum contents in a high-tungsten and low-molybdenum solution by using an energy dispersive X-ray fluorescence analyzer. Background technology:

[0002] In the process of tungsten hydrometallurgy, the content of tungsten and molybdenum in the control solution is a very important monitoring indicator. The analysis method generally adopts the thiocyanate colorimetric method, which takes a long time to analyze and uses reagents such as hydrochloric acid and sulfuric acid, which are easy to pollute the environment. In order to improve the analysis efficiency and reduce environmental pollution, X-ray fluorescence analyzer is now often used to analyze the tungsten and molybdenum in the control solution during tungsten hydrometallurgy.

[0003] According to the different spectral methods, X-ray fluorescence analysis can be divided into two categories: energy dispersive and wavelength dispersive, which are usually called energy spectrometers and wave spectrometers, abbreviated as EDXRF and WDXRF. Among them, the price of the wave spectrometer is expensive, generally more than 1 million, so in order to save money, the energy spectrometer will be chosen.

[0004] However, the tungsten hydrometallurgy process is long, and the tungsten and molybdenum content of the control solution is different. In the process of using the energy dispersive X-ray fluorescence analyzer, it is found that the determination of molybdenum in high-tungsten and low-molybdenum solutions (WO3: 180-300g / L, Mo: 1-5g / L) will be seriously interfered by tungsten, resulting in incorrect measurement results. So how can we accurately measure the tungsten and molybdenum content in high-tungsten and low-molybdenum solutions through an energy dispersive X-ray fluorescence analyzer? Summary of the invention:

[0005] In view of the fact that the determination of molybdenum in a high-tungsten and low-molybdenum solution by an energy dispersive X-ray fluorescence analyzer may be interfered by tungsten, the present invention provides a method for determining the tungsten and molybdenum contents in a high-tungsten and low-molybdenum solution by using an energy dispersive X-ray fluorescence analyzer, which solves the problem in the above background technology that the Mo content in the high-tungsten and low-molybdenum solution is incorrectly determined by the energy dispersive X-ray fluorescence analyzer because the WO3 content is much greater than the Mo content.

[0006] To achieve the above objectives, the present invention is implemented by the following technical scheme: A method for determining the tungsten and molybdenum content in a high-tungsten and low-molybdenum solution by energy dispersive X-ray fluorescence analysis, comprising the following steps:

[0007] A method for determining the tungsten and molybdenum content in a high-tungsten and low-molybdenum solution using an energy dispersive X-ray fluorescence analyzer, wherein the concentration of WO3 in the high-tungsten and low-molybdenum solution is in the range of 180 to 300 g / L and the concentration of Mo is in the range of 1 to 5 g / L; the method comprises the following steps:

[0008] 1) Prepare multiple standard samples for measuring WO3 curve;

[0009] 2) Determine the WO3 and Mo values ​​of each sample in step 1) by colorimetry;

[0010] 3) Prepare multiple standard samples for measuring Mo curve;

[0011] 4) Determine the WO3 and Mo values ​​of each sample in step 3) by colorimetry;

[0012] 5) Using an energy spectrometer to measure the working curve of WO3 in a high-tungsten and low-molybdenum solution;

[0013] 6) Using an energy spectrometer to measure the working curve of Mo in a high-tungsten and low-molybdenum solution;

[0014] 7) Correction coefficient working curve;

[0015] 8) Determine the sample to be tested, obtain the correction coefficient of Mo of the sample and calculate the Mo content.

[0016] The specific steps of step 1) preparing multiple standard samples for measuring WO3 curves are:

[0017] Select an ammonia solution with a higher WO3 content in the central control solution after colorimetry as the standard sample, set the sample number as 1#, and set it as the benchmark; prepare 2#, 3#, 4#, 5#, 6#, 7#, 8#, and 9# standard samples by adding ammonium molybdate solution and ammonia water to the sample, so as to obtain standard samples with a gradient distribution of WO3 content and basically consistent Mo content, and pour the above samples into measuring cups for later use.

[0018] The specific steps of step 3) preparing multiple standard samples for determining the Mo curve are as follows: select an ammonia solution with a higher WO3 content in the central control solution after the colorimetric method is used as the standard sample, set the sample number as 10#, and set it as the benchmark, and prepare 11#, 12#, 13#, 14#, and 15# standard samples by adding ammonium molybdate solution and ammonia water to the sample, so as to obtain standard samples with basically consistent WO3 content and gradient distribution of Mo content, and pour the above samples into measuring cups for standby use.

[0019] The method of using an energy spectrometer to determine the working curve of WO3 in a high-tungsten and low-molybdenum solution in step 5) is: select the standard sample for determining the WO3 curve in step 1), perform the determination according to the instrument operating instructions, input the fixed value of WO3 in step 2), and the instrument automatically generates the WO3 analysis working curve.

[0020] The method for determining the working curve of Mo in the high-tungsten and low-molybdenum solution using an energy spectrometer in step 6) is as follows: select the standard sample for determining the Mo curve in step 3), perform the determination according to the instrument operating instructions, input the fixed value of Mo in step 4), and the instrument automatically generates the Mo analysis working curve.

[0021] The method of the step 7) correcting the coefficient working curve is: select the standard sample for measuring the WO3 curve in step 1) and measure it under the working curve of Mo in step 6) to obtain the Mo data b, and then compare it with the Mo concentration a of each sample in step 2), and establish the working curve with the obtained ratio a / b as the vertical coordinate and the WO3 concentration of each sample in step 2) as the horizontal coordinate.

[0022] The step 8) of sample determination, obtaining the correction coefficient of sample Mo and calculating the content of Mo is as follows:

[0023] 8.1) Place the sample to be tested into a measuring cup and measure it under the selected WO3 working curve. The WO3 data in the solution measured under the curve is the WO3 concentration of the solution;

[0024] 8.2) Substitute the WO3 concentration of the solution into the correction coefficient working curve to calculate the sample Mo concentration correction coefficient = 0.0046 × solution WO3 concentration + 0.0908;

[0025] 8.3) Place the sample to be tested into the measuring cup and measure it under the selected Mo working curve. The Mo data in the solution measured under the curve, multiplied by the correction factor, is the Mo concentration of the solution.

[0026] In step 1), the concentration of the ammonium molybdate solution is 25 g / L, and the concentration of the ammonia water is 2 mol / L.

[0027] In step 2), the concentration of the ammonium molybdate solution is 100 g / L, and the concentration of the ammonia water is 2 mol / L. The present invention brings the following effects through the above scheme:

[0028] The method solves the problem of inaccurate determination of molybdenum content in high-tungsten and low-molybdenum solutions by energy dispersive X-ray fluorescence analyzer, is simple to operate, has accurate measurement data, saves analysis time, and avoids environmental pollution. Description of the drawings:

[0029] Figure 1 It is a schematic diagram of the correction coefficient working curve. Specific implementation method:

[0030] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0031] Instrument measurement conditions: The equipment used is the energy dispersive X-ray fluorescence spectrometer NEXQC produced by Rigaku Corporation of Japan, with a voltage of 30 kV and a current of 20 μA.

[0032] Sample preparation: The instruments used are XRF sample measuring cup and Mylar membrane produced by Chemplex Industries, Inc., USA;

[0033] Measuring cup specifications: one end of the cup is sealed, diameter 31mm×height 22.4mm, volume 9mL; Mylar film specifications: thickness 6μm*×width 7.6cm×length 91.4m.

[0034] Slowly pour the solution to about 8 mL in the XRF sample measuring cup, cover with Mylar film, tighten with the sample cup ring, then turn over so that the Mylar film faces downward, observe, and measure if there is no solution leakage; if the solution is turbid, filter it with filter paper first.

[0035] A method for determining the tungsten and molybdenum content in a high-tungsten and low-molybdenum solution using an energy dispersive X-ray fluorescence analyzer, wherein the concentration of WO3 in the high-tungsten and low-molybdenum solution is in the range of 180 to 300 g / L and the concentration of Mo is in the range of 1 to 5 g / L; the method comprises the following steps:

[0036] 1) Prepare multiple standard samples for determining WO3 curve: select a certain ammonia solution with a higher WO3 content in the central control solution after colorimetry as the standard sample, sample number 1#, and set it as the benchmark. By adding ammonium molybdate solution and ammonia water to the sample, prepare 2#, 3#, 4#, 5#, 6#, 7#, 8#, and 9# standard samples, so as to obtain standard samples with a gradient distribution of WO3 content and basically the same Mo content. The specific addition amounts are shown in Table 1, wherein the concentration of ammonium molybdate solution is 25 g / L, and the concentration of ammonia water is 2 mol / L.

[0037] Table 1 WO3 determination curve standard sample ratio table

[0038]

[0039]

[0040] 2) To ensure the accuracy of the standard sample results, the WO3 and Mo of each sample in step 1) were determined by colorimetry; the analysis results are shown in Table 2.

[0041] Table 2 WO3 determination curve standard sample fixed value table

[0042]

[0043] 3) Prepare multiple standard samples for determining the Mo curve: select an ammonia solution with a higher WO3 content in the central control solution after colorimetry as the standard sample, sample number 10#, and set it as the benchmark. By adding ammonium molybdate solution and ammonia water to the sample, prepare 11#, 12#, 13#, 14#, and 15# standard samples, so as to obtain standard samples with basically consistent WO3 content and gradient distribution of Mo content. The specific addition amounts are shown in Table 3, where the concentration of ammonium molybdate solution is 100 g / L and the concentration of ammonia water is 2 mol / L.

[0044] Table 3 Mo determination curve standard sample ratio table

[0045]

[0046]

[0047] 4) To ensure the accuracy of the standard sample results, the WO3 and Mo of each sample in step 3) were determined by colorimetry. The analysis results are shown in Table 4.

[0048] Table 4 WO3 determination curve standard sample fixed value table

[0049]

[0050] 5) Establish the working curve of energy dispersive X-ray fluorescence analyzer for determining WO3 in high-tungsten and low-molybdenum solution: Select the WO3 determination curve standard sample, perform the determination according to the instrument operating instructions, input the fixed value of WO3 in Table 2, and the instrument automatically generates the WO3 analysis working curve.

[0051] 6) Establishing the working curve for determining Mo in high-tungsten and low-molybdenum solutions by energy dispersive X-ray fluorescence analyzer: Select the Mo determination curve standard sample, perform the determination according to the instrument operating instructions, input the fixed value of Mo in Table 4, and the instrument automatically generates the Mo analysis working curve.

[0052] 7) Correction coefficient working curve: Select the WO3 determination curve standard sample and measure it under the Mo working curve to obtain the Mo data b, and then compare it with the Mo concentration a in Table 2, with the obtained ratio a / b as the ordinate and the WO3 concentration in Table 2 as the abscissa. The specific data is shown in Table 5, and the established working curve is shown in Figure 1 .

[0053] Table 5 Correction coefficient working curve

[0054]

[0055]

[0056] 8) Sample determination, obtain the correction coefficient of sample Mo and calculate the Mo content:

[0057] 8.1) Place the sample to be tested into a measuring cup and measure it under the selected WO3 working curve. The WO3 data in the solution measured under the curve is the WO3 concentration of the solution;

[0058] 8.2) Substitute the WO3 concentration of the solution into the correction coefficient working curve to calculate the sample Mo concentration correction coefficient = 0.0046 × solution WO3 concentration + 0.0908;

[0059] 8.3) Place the sample to be tested into the measuring cup and measure it under the selected Mo working curve. The Mo data in the solution measured under the curve, multiplied by the correction factor, is the Mo concentration of the solution.

[0060] Sample Mo concentration = measured Mo data in solution × sample Mo concentration correction factor. The precision and accuracy of the present invention are tested through multiple groups of experiments.

[0061] 1. Precision experiment

[0062] The actual production samples 0817-1 and 8# samples were selected to measure WO3 and Mo respectively under the established working curve. The measurements were performed 11 times and the results are shown in Table 6 below.

[0063] Table 6 Precision data

[0064]

[0065]

[0066] The general analysis method requires precision RSD < 5%. From the experimental data in Table 6, it can be seen that the relative standard deviations of WO3 and Mo in the solution measured by the energy dispersive X-ray fluorescence analyzer are both less than 5%, and the analysis results are stable and reliable.

[0067] 2. Accuracy experiment

[0068] Standard samples 1# to 9# and 10 production samples were selected for energy dispersive X-ray fluorescence analysis and colorimetric analysis to determine the concentrations of WO3 and Mo in the solution. The comparison of experimental data is shown in Table 7.

[0069] Table 7 Accuracy data

[0070]

[0071]

[0072] In the control and analysis of tungsten smelting, the analysis error of high-concentration WO3 is generally controlled within 5%, and the analysis error of low-concentration Mo is controlled within 10%. From the data in Table 7, it can be seen that the analysis deviation of the results obtained by this method and the colorimetric method is very small, both within this error range, indicating that this method is accurate and reliable.

[0073] The method solves the problem of inaccurate determination of molybdenum content in high-tungsten and low-molybdenum solutions by energy dispersive X-ray fluorescence analyzer, is simple to operate, has accurate measurement data, saves analysis time, and avoids environmental pollution.

[0074] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for determining the tungsten and molybdenum content in a high-tungsten and low-molybdenum solution using an energy dispersive X-ray fluorescence analyzer, characterized in that: In the high-tungsten and low-molybdenum solution, the concentration range of WO3 is 180-300 g / L, and the concentration range of Mo is 1-5 g / L; The steps include: 1) Prepare multiple standard samples for measuring WO3 curve; Select an ammonia solution with a higher WO3 content in the central control solution after colorimetric value determination as a standard sample, set the sample number as 1#, and set it as a benchmark; prepare 2#, 3#, 4#, 5#, 6#, 7#, 8#, and 9# standard samples by adding ammonium molybdate solution and ammonia water to the sample, so as to obtain standard samples with a gradient distribution of WO3 content and basically the same Mo content, and pour the above samples into a measuring cup for standby use; 2) Determine the WO3 and Mo values ​​of each sample in step 1) by colorimetry; 3) Prepare multiple standard samples for measuring Mo curve; Select an ammonia solution with a higher WO3 content in the central control solution after colorimetry as the standard sample, set the sample number as 10#, and set it as the benchmark. By adding ammonium molybdate solution and ammonia water to the sample, prepare 11#, 12#, 13#, 14#, and 15# standard samples, so as to obtain standard samples with basically consistent WO3 content and gradient distribution of Mo content. Pour the above samples into the measuring cup for use; 4) Determine the WO3 and Mo values ​​of each sample in step 3) by colorimetry; 5) Using an energy spectrometer to measure the working curve of WO3 in a high-tungsten and low-molybdenum solution; 6) Using an energy spectrometer to measure the working curve of Mo in a high-tungsten and low-molybdenum solution; 7) Correction coefficient working curve; Select the standard sample for measuring the WO3 curve in step 1) and measure it under the working curve of Mo in step 6) to obtain the Mo data b, and then compare it with the Mo concentration a of each sample in step 2), and establish the working curve with the obtained ratio a / b as the ordinate and the WO3 concentration of each sample in step 2) as the abscissa; 8) Determine the sample to be tested, obtain the correction coefficient of Mo of the sample and calculate the Mo content; the specific steps are: 8.1) Place the sample to be tested into the measuring cup and measure it under the selected WO3 working curve. The WO3 data in the solution measured under the curve is the WO3 concentration of the solution; 8.2) Substitute the WO3 concentration of the solution into the correction coefficient working curve to calculate the sample Mo concentration correction coefficient = 0.0046 × solution WO3 concentration + 0.0908; 8.3) Place the sample to be tested into the measuring cup and measure it under the selected Mo working curve. The Mo data in the solution measured under the curve, multiplied by the correction factor, is the Mo concentration of the solution.

2. The method for determining the tungsten and molybdenum content in a high-tungsten and low-molybdenum solution using an energy dispersive X-ray fluorescence analyzer according to claim 1, characterized in that: The method of using an energy spectrometer to determine the working curve of WO3 in the high-tungsten and low-molybdenum solution in step 5) is as follows: select the standard sample for determining the WO3 curve in step 1), perform the determination according to the instrument operating instructions, input the fixed value of WO3 in step 2), and the instrument automatically generates the WO3 analysis working curve.

3. The method for determining the tungsten and molybdenum content in a high-tungsten and low-molybdenum solution using an energy dispersive X-ray fluorescence analyzer according to claim 1, characterized in that: The method for determining the working curve of Mo in the high-tungsten and low-molybdenum solution using an energy spectrometer in step 6) is as follows: select the standard sample for determining the Mo curve in step 3), perform the determination according to the instrument operating instructions, input the fixed value of Mo in step 4), and the instrument automatically generates the Mo analysis working curve.

4. The method for determining the tungsten and molybdenum content in a high-tungsten and low-molybdenum solution using an energy dispersive X-ray fluorescence analyzer according to claim 1, characterized in that: In step 1), the concentration of the ammonium molybdate solution is 25 g / L, and the concentration of the ammonia water is 2 mol / L.

5. The method for determining the tungsten and molybdenum content in a high-tungsten and low-molybdenum solution using an energy dispersive X-ray fluorescence analyzer according to claim 1, characterized in that: In step 2), the concentration of the ammonium molybdate solution is 100 g / L, and the concentration of the ammonia water is 2 mol / L.

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