A method for rapidly determining the content of niobium in a bayin obo niobium-containing mineral

Abstract

The application discloses a kind of quick determination methods of niobium content in Baiyunebo niobium-containing mineral, because of the scarcity of Baiyunebo niobium-containing mineral standard sample, considering the pertinence of detection method to Baiyunebo niobium-containing mineral and the coverage of standard curve linearity, accurately weigh a certain mass of existing standard sample, mixed into mixed standard sample, to obtain the required content standard sample, the mixed standard sample is obtained by accurately weighing two standard samples with known content, and is fully mixed on a speed-adjusting oscillator;And the calculation formula of the content of mixed standard sample is summarized, which can be used for the calculation of other mixed standard sample content.This application compared with prior art, solves the particle size effect and mineral effect caused by tabletting analysis, can effectively improve the analysis speed of niobium content in Baiyunebo niobium-containing mineral, improve the accuracy of analysis data, with the characteristics of simple operation, practical, reasonable determination method provides reliable technical support for beneficiation and metallurgy.

Description

Technical Field

[0001] This invention relates to the field of analytical testing, and in particular to a rapid method for determining the niobium content in niobium-bearing minerals from Bayan Obo. Background Technology

[0002] Niobium is an important resource, playing a vital role in various key sectors of the national economy, including petrochemicals, steel, and shipbuilding. In recent years, the industry has primarily used nitric acid, hydrofluoric acid, and tartaric acid to decompose niobium-containing minerals. However, this process is time-consuming and cumbersome. Furthermore, the Bayan Obo mine is a polymetallic deposit containing 71 elements, including iron, rare earth elements, niobium, and scandium. Therefore, the composition and properties of niobium-containing minerals in this region are complex, requiring different decomposition methods than those for single niobium minerals. The variety of niobium minerals presents challenges for analysis and detection, and traditional chemical analysis cannot accurately guide beneficiation and smelting production.

[0003] Currently, there are no national or industry standards for the determination of niobium content in niobium-bearing minerals in Bayan Obo, Baotou. Chinese patent CN 101609048A provides a method for determining niobium content in ferronickel using ICP-AES, which significantly improves the accuracy and reliability of the detection results by dissolving niobium in ferronickel with a mixed acid. However, this patent only detects niobium in ferronickel, limiting its scope and preventing the detection of niobium in niobium-bearing minerals. Chinese patent CN 114577891A introduces a method for determining scandium and niobium in tailings from the Bayan Obo beneficiation ore mine in Baotou using ICP-MS. This method is cumbersome and time-consuming, failing to meet the need for rapid determination. With the accelerating pace of comprehensive utilization of mineral resources, the rapid determination of niobium content in niobium-bearing minerals in Bayan Obo, Baotou, is particularly important. Summary of the Invention

[0004] To address the aforementioned technical problems, the purpose of this invention is to provide a rapid method for determining the niobium content in niobium-bearing minerals from Bayan Obo.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] This invention provides a rapid method for determining the niobium content in niobium-bearing minerals from Bayan Obo, comprising the following steps:

[0007] (1) Selection of standard samples:

[0008] Niobium-bearing minerals in Bayan Obo mostly exist in the form of niobium pentoxide. Due to the scarcity of standard samples of Bayan Obo niobium-bearing minerals, there are currently three Baotou minerals of the same matrix type as the sample to be tested: BK-3, R715, and R717. Considering the specificity of the detection method for Bayan Obo niobium-bearing minerals and the coverage of the linearity of the standard curve, a certain mass of R715 and R717 were accurately weighed and mixed into one mixed standard sample. The details are shown in Table 1 below.

[0009] Table 1. List of Standard Samples and Mixed Standard Samples

[0010] Standard Sample Number <![CDATA[Content of ωNb2O5 (%)]]> Baotou Mine BK-3 0.098 Baotou Mine R715 0.042 Baotou Mine R717 0.360 Baotou Mine Mixed Ore R715+R717 0.199

[0011] The Baotou mixed ore in Table 1 was obtained as follows: MR715 g of Baotou ore R715 was accurately weighed into the mixing ball of the automatic speed-regulating shaker, and MR717 g of Baotou ore R717 was accurately weighed. The ball was covered and tightened, and placed on the automatic speed-regulating shaker for low-speed vibration for 15 minutes, and then adjusted to high-speed vibration for 10 minutes to obtain a uniform Baotou ore mixed ore.

[0012] The Nb₂O₅ content of the mixed ore from Baotou mine in Table 1 was calculated using the following formula:

[0013]

[0014] Where, ω 混 Nb2O5 content of mixed ore from Baotou mine, in %;

[0015] M R715 The sample weight of Baotou Mine R715 is in grams.

[0016] ω R715 Nb2O5 content of Baotou mine R715, in %;

[0017] M R717 The sample weight of Baotou Mine R717 is in grams.

[0018] ω R717 Nb2O5 content of Baotou mine R717, in %;

[0019] M: Weight of each standard sample, in grams;

[0020] (2) Pre-oxidation:

[0021] Accurately weigh several standard samples of niobium-bearing minerals with a certain concentration gradient from the Bayan Obo mining area into a square magnetic boat. After calcination and oxidation in a box-type resistance furnace, place the magnetic boat containing the calcined material on an asbestos board and cool it to room temperature.

[0022] (3) Sample melting:

[0023] After cooling, the standard sample is transferred from the magnetic boat to a platinum crucible. Lithium nitrate and mixed flux are added to the platinum crucible, and the mixture is stirred with a glass rod to ensure uniform mixing. Then, lithium bromide release agent is added dropwise. The platinum crucible containing the standard sample, lithium nitrate, and mixed solvent is placed in a high-frequency melting furnace for melting. After melting, the sample is removed and cooled to room temperature to obtain a standard sample glass slide. The standard sample number and content information are labeled on the surface of the glass slide for later use.

[0024] (4) Plot the calibration curve:

[0025] In X-ray fluorescence analysis, Compton scattering internal standard correction can significantly reduce the influence of organismal effects; a working curve is plotted with the (NbKa / RhKaC) intensity ratio as the ordinate and the concentration C (Nb2O5%) as the abscissa.

[0026] (5) Weigh the same weight of the niobium-containing mineral sample to be tested as in step (2), and prepare the glass sample to be tested according to steps (2) and (3). Under the same measurement conditions as in step (4), determine the niobium content in the niobium-containing mineral sample to be tested according to the calibration curve in step (4).

[0027] Furthermore, in step (2), each standard sample is 0.6000g, the calcination oxidation temperature is 850℃, and before calcination oxidation, the box-type resistance furnace is preheated to 850℃ and the calcination time is 30min.

[0028] Furthermore, in step (3), 1.0 g of lithium nitrate, 6.0 g of mixed flux, and 6 drops of 12 mg / ml lithium bromide release agent are added to the standard sample transferred from the magnetic boat to the platinum crucible.

[0029] Furthermore, the mixed flux is lithium tetraborate or a mixed solvent prepared by lithium tetraborate and lithium metaborate in a mass ratio of 67:33.

[0030] Furthermore, the melting process in step (3) is as follows:

[0031] The platinum crucible containing the sample was placed in a high-frequency melting machine and further oxidized at 750°C for 6 minutes.

[0032] Increase the temperature to 1100℃ and melt for 8 minutes;

[0033] Self-cool for 2 minutes, then air-cool for 1 minute, and then cool to room temperature.

[0034] Furthermore, in the melting process (1), the furnace body is stationary; in the process (2), the furnace body is slowly oscillating, while the support rotates to drive the crucible to rotate, so as to achieve the effect of shaking evenly; in the process (3), the furnace body is stationary.

[0035] Furthermore, in step (3), the sample melting process can melt four samples at a time.

[0036] Furthermore, the detection range of this method is: Nb2O5: 0.010% to 0.36%.

[0037] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0038] The X-ray fluorescence spectrometry fusion method was used to solve the problem of niobium content in niobium-bearing minerals in Bayan Obo, filling a gap in the determination of niobium content in these minerals.

[0039] The Nb2O5 content in niobium-bearing minerals in Bayan Obo ranges from 0.020% to 0.25%. Based on this characteristic, the detection range of this method is 0.010% to 0.36% for Nb2O5, covering the range of niobium content in niobium-bearing minerals in this mining area.

[0040] Due to the scarcity of niobium-bearing mineral standard samples in Bayan Obo, and considering the specificity of the detection method for Bayan Obo niobium-bearing minerals and the coverage of the linearity of the standard curve, a certain mass of existing standard samples was accurately weighed and mixed to form a mixed standard sample to obtain the standard sample with the required content. The mixed standard sample was obtained by accurately weighing two standard samples with known contents and thoroughly mixing them on a speed-controlled oscillator. Furthermore, a formula for calculating the content of the mixed standard sample was summarized, which can be extended to calculate the content of other mixed standard samples.

[0041] In view of the high sulfur content in niobium-bearing minerals in the Bayan Obo area, this method adopts the following approach: first, pre-oxidize by calcining in an 850℃ box-type resistance furnace for 30 minutes, and then further oxidize by using lithium nitrate as an oxidant during the melting process. This achieves a good oxidation effect and successfully prepares niobium-bearing mineral glass slides without causing reducing corrosion to the platinum crucible.

[0042] Internal standard correction was performed using Compton scattering lines, and working curves were plotted with the (NbKa / RhKaC) intensity ratio as the ordinate and the concentration C (Nb2O5%) as the abscissa, which significantly reduced the impact of organismal effects.

[0043] The entire analysis of a single sample takes about 1.5 to 2.0 hours. Since the melting process can be performed in groups of four and the calcination pre-oxidation process can be performed on multiple samples simultaneously, the method has a very high detection efficiency.

[0044] Compared with existing technologies, this invention solves the problems of particle size effect and mineral effect caused by tableting analysis, effectively improves the analysis speed of niobium content in niobium-bearing minerals in Bayan Obo, and improves the accuracy of analysis data. It is simple to operate and practical, and the reasonable determination method provides reliable technical support for mineral processing and metallurgy. Attached Figure Description

[0045] The present invention will be further described below with reference to the accompanying drawings.

[0046] Figure 1 Standard working curve established for niobium-containing standard samples Detailed Implementation

[0047] A rapid method for determining the niobium content in niobium-bearing minerals from Bayan Obo, comprising:

[0048] 1. Selection of standard samples: Due to the scarcity of standard samples of niobium-bearing ore in Bayan Obo, there are three existing samples of the same matrix type as the sample to be tested: Baotou ore BK-3, R715, and R717. Considering the specificity of the detection method for Bayan Obo niobium-bearing ore and the coverage of the linearity of the standard curve, a certain mass of R715 and R717 were accurately weighed and mixed into one mixed standard sample. The details are shown in Table 1 below.

[0049] Table 1. List of Standard Samples and Mixed Standard Samples

[0050] Standard Sample Number <![CDATA[Content of ωNb2O5 (%)]]> Baotou Mine BK-3 0.098 Baotou Mine R715 0.042 Baotou Mine R717 0.360 Baotou Mine Mixed Ore R715+R717 0.199

[0051] The mixed ore from Baotou in Table 1 was obtained as follows: M was accurately weighed into the mixing ball of an automatic speed-regulating shaker. R715 g Baotou ore R715, then accurately weigh M R717 For g Baotou ore R717, cover and tighten the small ball, place it on an automatic speed-adjusting oscillator and vibrate at low speed for 15 minutes, then adjust to high speed and vibrate for 10 minutes to obtain a uniform Baotou ore mixture.

[0052] The Nb₂O₅ content of the mixed ore from Baotou mine in Table 1 was calculated using the following formula:

[0053]

[0054] Where, ω 混 Nb2O5 content of mixed ore from Baotou mine, in %;

[0055] M R715 The sample weight of Baotou Mine R715 is in grams.

[0056] ω R715 Nb2O5 content of Baotou mine R715, in %;

[0057] M R717 The sample weight of Baotou Mine R717 is in grams.

[0058] ω R717 Nb2O5 content of Baotou mine R717, in %;

[0059] M: Weight of each standard sample, in grams;

[0060] 2. Pre-oxidation: Accurately weigh several standard samples of niobium-bearing minerals from the Bayan Obo mining area with a certain concentration gradient into a square magnetic boat. After calcination and oxidation in a box-type resistance furnace, place the magnetic boat containing the calcined material on an asbestos board and cool it to room temperature.

[0061] 3. Sample melting: Transfer the cooled standard sample from the magnetic boat to a platinum crucible. Add lithium nitrate and mixed flux to the platinum crucible and stir with a glass rod to mix them evenly. Then, drop in lithium bromide release agent. Place the platinum crucible containing the standard sample, lithium nitrate, and mixed solvent into a high-frequency melting furnace for melting. After melting, remove the crucible and cool it to room temperature to obtain a standard sample glass slide. Label the surface of the glass slide with the standard sample number and content information, and set it aside for later use.

[0062] 4. Plot the calibration curve: Plot the working curve with the intensity ratio (NbKa / RhKaC) as the ordinate and the concentration C (Nb2O5%) as the abscissa.

[0063] 5. Weigh the same weight of the niobium-containing mineral sample to be tested as in step 2, prepare the glass sample to be tested according to steps 2 and 3, and determine the content of niobium pentoxide in the niobium-containing mineral sample to be tested under the same measurement conditions as in step 4.

[0064] In step 2 of this invention, each standard sample weighs 0.6000g, the calcination oxidation temperature is 850℃, and before calcination oxidation, the box-type resistance furnace is preheated to 850℃ and the calcination time is 30min.

[0065] In step 3, 1.0 g of lithium nitrate, 6.0 g of mixed flux, and 6 drops of 12 mg / ml lithium bromide release agent were added to the standard sample transferred from the magnetic boat to the platinum crucible.

[0066] The mixed flux can be lithium tetraborate or a mixed solvent prepared by lithium tetraborate and lithium metaborate in a mass ratio of 67:33.

[0067] The melting process in step 3 of this invention is as follows:

[0068] (1) The platinum crucible containing the sample was placed in a high-frequency melting machine and further oxidized at 750°C for 6 min.

[0069] (2) Increase the temperature to 1100℃ and melt for 8 minutes;

[0070] (3) Self-cool for 2 minutes, then air-cool for 1 minute, and then cool to room temperature.

[0071] In the melting process (1), the furnace body is stationary; in the process (2), the furnace body swings slowly, while the support rotates to drive the crucible to rotate, so as to achieve the effect of shaking evenly; in the process (3), the furnace body is stationary.

[0072] Example 1

[0073] 1. Selection of standard samples: Due to the scarcity of standard samples of niobium-bearing ore in Bayan Obo, there are three existing samples of the same matrix type as the sample to be tested: Baotou ore BK-3, R715, and R717. Considering the specificity of the detection method for Bayan Obo niobium-bearing ore and the coverage of the linearity of the standard curve, a certain mass of R715 and R717 were accurately weighed and mixed into one mixed standard sample. The details are shown in Table 1 below.

[0074] Table 1. List of Standard Samples and Mixed Standard Samples

[0075] Standard Sample Number <![CDATA[Content of ωNb2O5 (%)]]> Baotou Mine BK-3 0.098 Baotou Mine R715 0.042 Baotou Mine R717 0.360 Baotou Mine Mixed Ore R715+R717 0.199

[0076] In Table 1, the Baotou ore mixed ore with an Nb2O5 content of 0.199% was obtained by the following method: M was accurately weighed into the mixing ball of an automatic speed-regulating shaker. R715 g Baotou ore R715, then accurately weigh M R717 For g Baotou ore R717, cover and tighten the small ball, place it on an automatic speed-adjusting oscillator and vibrate at low speed for 15 minutes, then adjust to high speed and vibrate for 10 minutes to obtain a uniform Baotou ore mixture.

[0077] The Nb₂O₅ content of the mixed ore from Baotou mine in Table 1 was calculated using the following formula:

[0078]

[0079] Where, ω 混 Nb2O5 content of mixed ore from Baotou mine, in %;

[0080] M R715 The sample weight of Baotou Mine R715 is in grams.

[0081] ω R715 Nb2O5 content of Baotou mine R715, in %;

[0082] M R717 The sample weight of Baotou Mine R717 is in grams.

[0083] ω R717 Nb2O5 content of Baotou mine R717, in %;

[0084] M: Weight of each standard sample, in grams;

[0085] In this implementation case, M R715=0.3038g, M R717 =0.2962g, M=0.6000±0.0002g. Considering process losses and reserves, weigh the mixed sample in three times the amount. Weigh R715 as 0.9114±0.0002g and R717 as 0.8886±0.0002g.

[0086] 2. Accurately weigh the niobium-bearing mineral standard samples listed in Table 1 from the Bayan Obo mining area. Weigh 0.6000±0.0002g of each standard sample directly into a square magnetic boat. Place the boat in a box-type resistance furnace preheated to 850℃ for 30min for oxidation treatment. Then place the magnetic boat containing the calcined material on an asbestos board and cool it to room temperature.

[0087] 3. Transfer the cooled standard sample from the magnetic boat to a platinum crucible. Add 1.0 g of lithium nitrate and 6.0 g of mixed flux to the platinum crucible, and stir with a glass rod until homogeneous. Then add 6 drops of 12 mg / ml lithium bromide release agent. Place the platinum crucible containing the standard sample, lithium nitrate, and mixed solvent into a high-frequency melting machine preheated to 750°C. Further oxidize for 6 minutes, raise the temperature to 1100°C, melt for 8 minutes, self-cool for 2 minutes, and air-cool for 1 minute. Remove and cool to room temperature to obtain a standard sample glass slide. Label the surface of the glass slide with the standard sample number and content information, and set aside for later use.

[0088] 4. Plot the working curve with the intensity ratio (NbKa / RhKaC) as the ordinate and the concentration C (Nb2O5%) as the abscissa. The measurement conditions for the measured elements and internal standard elements are selected as shown in Table 2 below.

[0089] Table 2. Operating conditions for the spectrometer for measuring elements and internal standard elements.

[0090]

[0091]

[0092] 5. Weigh 0.6000g of the niobium-containing mineral sample to be tested, and prepare the glass sample to be tested according to steps 2 and 3. Under the same measurement conditions as in step 4, determine the niobium content in the niobium-containing mineral sample according to the calibration curve in step 4.

[0093] Example 2: Detection limit of a rapid method for determining niobium content in niobium-bearing minerals in Bayan Obo

[0094] After establishing the calibration curve as described above, glass slides containing only flux, oxidant, and release agent were used as blank slides for the detection method. The measured values ​​on the blank slides were the method blank values. Eleven blank glass slides were prepared according to the experimental method. Eleven blank solutions were prepared and measured three times. The method detection limit Nb₂O₅ was calculated to be 0.00093% according to the detection limit formula CL = 3Sb / k (where Sb is the standard deviation of the blank and k is the slope of the corresponding calibration curve) defined by the International Union of Pure and Applied Chemistry (IUPAC). The results are shown in Table 3 below.

[0095] Table 3 Method Detection Limits

[0096]

[0097] As can be seen from Table 3, the detection limit is low, indicating that the method has high sensitivity and can meet the requirements for niobium determination.

[0098] Example 3: Precision Test

[0099] Six measurements were performed on the niobium-bearing mineral sample XK-60 from Bayan Obo, and the relative standard deviation (RSD) is used to represent the precision. The results are shown in Table 4 below:

[0100] Table 4 Precision Test Results

[0101]

[0102] As can be seen from Table 4 above, the relative standard deviation (RSD) of repeated measurements of samples is no greater than 5%, indicating high precision.

[0103] Example 4: Accuracy Test

[0104] Weigh the standard samples of Baotou ore (R715, R716, BK-1) and test them according to the above method. The results are shown in Table 5.

[0105] Table 5. Accuracy Measurement Results (%)

[0106]

[0107] As can be seen from Table 5, the method has high accuracy and can meet the requirements for niobium element determination.

[0108] Using this method to analyze blanks, dolomite standard samples, and niobium-bearing minerals in Bayan Obo, the experimental data show that this method has a low detection limit, good precision and accuracy, and fully meets the daily analysis requirements for niobium-bearing minerals in Bayan Obo.

[0109] This invention demonstrates good application results through multiple tests on the niobium content in niobium-bearing minerals from Bayan Obo.

[0110] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A rapid method for determining the niobium content in niobium-bearing minerals from Bayan Obo, characterized in that: Includes the following steps: (1) Selection of standard samples: Niobium-bearing minerals in Bayan Obo mostly exist in the form of niobium pentoxide. Due to the scarcity of standard samples of Bayan Obo niobium-bearing minerals, there are currently three Baotou minerals of the same matrix type as the sample to be tested: BK-3, R715, and R717. Considering the specificity of the detection method for Bayan Obo niobium-bearing minerals and the coverage of the linearity of the standard curve, a certain mass of R715 and R717 are accurately weighed and mixed into one mixed standard sample. (2) Pre-oxidation: Accurately weigh several standard samples of niobium-bearing minerals with a certain concentration gradient from the Bayan Obo mining area into a square magnetic boat. After calcination and oxidation in a box-type resistance furnace, place the magnetic boat containing the calcined material on an asbestos board and cool it to room temperature. (3) Sample melting: After cooling, the standard sample is transferred from the magnetic boat to a platinum crucible. Lithium nitrate and mixed flux are added to the platinum crucible, and the mixture is stirred with a glass rod to ensure uniform mixing. Then, lithium bromide release agent is added dropwise. The platinum crucible containing the standard sample, lithium nitrate, and mixed solvent is placed in a high-frequency melting furnace for melting. After melting, the sample is removed and cooled to room temperature to obtain a standard sample glass slide. The standard sample number and content information are labeled on the surface of the glass slide for later use. (4) Plot the calibration curve: In X-ray fluorescence analysis, Compton scattering internal standard correction can significantly reduce the influence of organismal effects; the working curve is plotted with the NbKa / RhKaC intensity ratio as the ordinate and the Nb2O5% concentration C as the abscissa, in %; (5) Weigh the same weight of the niobium-containing mineral sample to be tested as in step (2), and prepare the glass sample to be tested according to steps (2) and (3). Under the same measurement conditions as in step (4), determine the niobium content in the niobium-containing mineral sample to be tested according to the calibration curve in step (4).

2. The method for rapidly determining the content of niobium in a Bayan Obo niobium-bearing mineral according to claim 1, characterized in that: In step (2), each standard sample is 0.6000g, the calcination oxidation temperature is 850℃, and before calcination oxidation, the box-type resistance furnace is preheated to 850℃ and the calcination time is 30min.

3. The method for rapidly determining the content of niobium in a Bayan Obo niobium-bearing mineral according to claim 2, characterized in that: In step (3), 1.0g of lithium nitrate, 6.0g of mixed flux, and 6 drops of 12mg / ml lithium bromide release agent are added to the standard sample transferred from the magnetic boat to the platinum crucible.

4. The method for rapidly determining the content of niobium in a Bayan Obo niobium-bearing mineral according to claim 1, characterized in that: The mixed flux is lithium tetraborate or a mixed solvent prepared by lithium tetraborate and lithium metaborate in a mass ratio of 67:

33.

5. The method for rapidly determining the content of niobium in a Bayan Obo niobium-bearing mineral according to claim 1, characterized in that: The melting process in step (3) is as follows: The platinum crucible containing the sample was placed in a high-frequency melting machine and further oxidized at 750°C for 6 minutes. Increase the temperature to 1100℃ and melt for 8 minutes; Self-cool for 2 minutes, then air-cool for 1 minute, and then cool to room temperature.

6. The method for rapidly determining the content of niobium in a Bayan Obo niobium-bearing mineral according to claim 1, characterized in that: In the melting process (1), the furnace body is stationary; in the process (2), the furnace body swings slowly, and at the same time the support rotates to drive the crucible to rotate, so as to achieve the effect of shaking evenly; in the process (3), the furnace body is stationary.

7. The method for rapidly determining the content of niobium in a Bayan Obo niobium-bearing mineral according to claim 1, characterized in that: The sample melting process in step (3) can melt four samples at a time.

8. The method for rapidly determining the content of niobium in a Bayan Obo niobium-bearing mineral according to claim 1, characterized in that: The detection range of this method is: Nb2O5: 0.010% to 0.36%.

Images