Manufacturing method of cobalt powder for fluorescence analysis of iron ore

Abstract

The invention discloses a preparation method of cobalt powder for fluorescence analysis of iron ore, and belongs to the technical field of analytical chemistry. The method comprises the following steps: weighing cobalt sesquioxide and anhydrous lithium tetraborate, uniformly mixing, transferring into a platinum yellow crucible, adding a proper amount of lithium bromide release agent, melting in a melting furnace according to a set mode, cooling, taking out, and grinding into powder; according to the method, the purchase cost of the cobalt powder can be effectively reduced, the process is simple, the production requirement can be met, and the technical support of a self-making method is provided for the cobalt powder for the iron ore fluorescence inspection method. When the cobalt powder prepared through the method is used for iron ore analysis, the analysis precision and accuracy can meet the requirements of similar standards, and the requirements of production and scientific research can be met.

Description

Technical Field

[0001] The invention belongs to the technical field of analytical chemistry, and in particular relates to a method for preparing cobalt powder for fluorescence analysis of iron ore. Background Art

[0002] When analyzing iron ore by X-ray fluorescence spectroscopy, due to the complex composition of iron ore, the high iron content and uneven distribution, the traditional fluorescence spectroscopy may be affected by particle size effect, mineral effect and matrix effect, resulting in inaccurate analysis results. Using cobalt as an internal standard, the element concentration can be calculated using data such as the internal standard intensity and the analysis line ratio or the intensity ratio of the analysis line and the target line coherent scattered line, thereby compensating for the absorption enhancement effect and instrument drift and improving the accuracy of the analysis. When cobalt trioxide is directly added during analysis, the weighing error is large due to the small weighing mass; in addition, cobalt trioxide is easy to stick to the weighing spoon and weighing dish, and the transfer process is prone to cause mass loss, resulting in inaccurate addition and affecting the test results. Summary of the invention

[0003] The purpose of the present invention is to provide a method for making cobalt powder with high analytical accuracy, economic reliability and the ability to meet the requirements of the iron ore fluorescence test method. Cobalt and iron are two elements with similar atomic numbers and relatively similar physical and chemical properties. Since the content of cobalt in general iron ore is very small (almost negligible), when using cobalt powder as an internal standard to perform X-ray fluorescence spectrometry analysis on iron, the influence of iron and other elements on the analysis results can be effectively eliminated.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides a method for preparing cobalt powder for fluorescence analysis of iron ore, the preparation method comprising the following steps:

[0005] Step 1: Weighing and mixing the medicine

[0006] ① Weigh 5.000g±0.0002g of anhydrous lithium tetraborate into a ceramic crucible;

[0007] ② Weigh 0.5000g±0.0002g of cobalt trioxide and place it in the ceramic crucible;

[0008] ③ Stir the weighed sample evenly and pour it into a platinum crucible;

[0009] ④Add 5 to 7 drops of release agent.

[0010] Furthermore, the release agent is lithium bromide, and the concentration of the lithium bromide is 400g / L.

[0011] Step 2: Sample preparation

[0012] ① Set the melting mode: 1st heat time 60 seconds, temperature reaches 800℃; 2nd heat time 120 seconds, temperature reaches 1020℃, after the temperature reaches 1020℃, melting for 240 seconds; self-cooling time 120 seconds, air cooling time 120 seconds. You can also set the melting temperature and time according to the actual situation to ensure that the sample is melted evenly and completely, and the sample is intact without cracks.

[0013] ② Select the set mode and start melting the sample; after melting the sample, remove the sample and make a fused sheet after it is completely cooled.

[0014] Step 3: Preparation of cobalt powder

[0015] ① Grinding the molten sheet into cobalt powder using a grinder, wherein the particle size of the cobalt powder is not greater than 0.16 mm;

[0016] ② Place the ground cobalt powder in a drying oven at 120°C and dry for 2 hours. The homemade cobalt powder is now complete.

[0017] The method first weighs cobalt trioxide and anhydrous lithium tetraborate, mixes them and transfers them into a platinum crucible, adds an appropriate amount of lithium bromide release agent, melts them in a melting furnace according to a set mode, takes them out after cooling and grinds them with a grinder, providing technical support for a homemade method for using cobalt powder in the fluorescent test method for iron ore.

[0018] When weighing cobalt trioxide and anhydrous lithium tetraborate, the accuracy must be ±0.0002g. Stir and mix thoroughly in a porcelain crucible. Do not stir in a platinum crucible to avoid scratching the platinum crucible and affecting its service life. The sample mixing and transfer process must be delicate, and no sample should be lost. During the melting process, no contaminants should fall into the crucible. The sample must be kept clean and damaged samples should be discarded directly; the grinding process must not be contaminated by other substances. The prepared cobalt powder is stored in a desiccator. If the storage period exceeds one month, it needs to be dried again before use.

[0019] A cobalt powder prepared by the above method, and application of the cobalt powder in fluorescence analysis of iron ore.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The invention can effectively reduce the purchase cost of cobalt powder, has a simple process and meets production requirements. The cobalt powder prepared by the method is used for iron ore analysis, and the precision and accuracy of the analysis can meet the requirements of similar standards, and can meet production and scientific research needs. DETAILED DESCRIPTION

[0022] The present invention is further described below in conjunction with specific examples, but the present invention is not limited in any way. To avoid redundant description, the raw materials in the following examples are all commercially available products unless otherwise specified, and the methods used are all conventional methods unless otherwise specified.

[0023] A method for preparing cobalt powder for fluorescence analysis of iron ore comprises the following steps:

[0024] Step 1: Weighing and mixing the medicine

[0025] ① Weigh 5.0000g±0.0002g of anhydrous lithium tetraborate into a ceramic crucible;

[0026] ② Weigh 0.5000g±0.0002g of cobalt trioxide and place it in the ceramic crucible;

[0027] ③ Stir the weighed sample evenly and pour it into a platinum crucible;

[0028] ④ Add 5 to 7 drops of release agent lithium bromide (400g / L);

[0029] Step 2: Sample preparation

[0030] After setting the melting mode, start melting the sample; after melting the sample, remove the sample and make a fused sheet after cooling completely;

[0031] Step 3: Preparation of cobalt powder

[0032] The molten sheet is ground into cobalt powder, and the particle size of the cobalt powder is not greater than 0.16 mm; the ground cobalt powder is placed in a drying oven at 120° C. and dried for 2 hours, and the homemade cobalt powder is completed.

[0033] The matters not described in the following embodiments are the same as the description of the above specific implementation methods.

[0034] Example 1

[0035] A method for preparing cobalt powder for fluorescence analysis of iron ore, the specific steps are:

[0036] Step 1: Weighing and mixing the medicine

[0037] ① Weigh 5.0000g of anhydrous lithium tetraborate into a ceramic crucible;

[0038] ② Weigh 0.5000 g of cobalt trioxide and place it in the ceramic crucible;

[0039] ③ Stir the weighed sample evenly and pour it into a platinum crucible;

[0040] ④ Add 5 drops of release agent lithium bromide (lithium bromide concentration is 400g / L).

[0041] Step 2: Sample preparation

[0042] Set the melting mode: the first heat time is 60 seconds, the temperature reaches 800℃; the second heat time is 120 seconds, the temperature reaches 1020℃, and after the temperature reaches 1020℃, melt for 240 seconds; self-cooling time is 120 seconds, and air cooling time is 120 seconds. Then start melting; after melting, remove the sample and make a fused sheet after cooling completely.

[0043] Step 3: Preparation of cobalt powder

[0044] The molten sheet is ground into cobalt powder, and the particle size of the cobalt powder is not greater than 0.16 mm; the ground cobalt powder is placed in a drying oven at 120° C. for drying, and the homemade cobalt powder is completed.

[0045] Example 2

[0046] A method for preparing cobalt powder for fluorescence analysis of iron ore, the specific steps are:

[0047] Step 1: Weighing and mixing the medicine

[0048] ① Weigh 5.0000g of anhydrous lithium tetraborate into a ceramic crucible;

[0049] ② Weigh 0.5000 g of cobalt trioxide and place it in the ceramic crucible;

[0050] ③ Stir the weighed sample evenly and pour it into a platinum crucible;

[0051] ④ Add 7 drops of release agent lithium bromide (400g / L).

[0052] Step 2: Sample preparation

[0053] Set the melting mode: 1st heat time 60 seconds, temperature reaches 800℃; 2nd heat time 120 seconds, temperature reaches 1020℃, after the temperature reaches 1020℃, melt for 240 seconds; self-cooling time 120 seconds, air cooling time 120 seconds, swing speed 4. Then start melting; after melting, remove the sample, and make a fused sheet after cooling completely.

[0054] Step 3: Preparation of cobalt powder

[0055] The molten sheet is ground into cobalt powder, and the particle size of the cobalt powder is not greater than 0.16 mm; the ground cobalt powder is placed in a drying oven at 120° C. for drying, and the homemade cobalt powder is completed.

[0056] Application Examples

[0057] The cobalt powder prepared in Example 1 was used to perform iron ore analysis (the iron ore samples were numbered Wkd88303a, YSBC28783-01, YSB46702-09, and GSB03-1693a-2015, respectively). The analysis results are shown in Table 1, indicating that the precision and accuracy of the analysis can meet the requirements of similar standards.

[0058] Table 1 Iron ore analysis results using the cobalt powder obtained in Example 1

[0059]

[0060]

[0061] For any technician familiar with the art, without departing from the scope of the technical solution of the present invention, the technical content disclosed above can be used to make many possible changes and modifications to the technical solution of the present invention, or modified into equivalent embodiments with equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention should still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A method for preparing cobalt powder for fluorescent analysis of iron ore, characterized in that: The production method comprises the following steps: Step 1: Weighing and mixing the medicine ① Weigh 5.000g±0.0002g of anhydrous lithium tetraborate into a ceramic crucible; ② Weigh 0.5000g±0.0002g of cobalt trioxide and place it in the ceramic crucible; ③ Stir the weighed sample evenly and pour it into a platinum crucible; ④Add release agent; Step 2: Sample preparation After setting the melting mode, start melting the sample; after melting the sample, remove the sample and make a fused sheet after cooling completely; Step 3: Preparation of cobalt powder The molten sheet is ground into cobalt powder, and the particle size of the cobalt powder is not greater than 0.16 mm; the ground cobalt powder is placed in a drying oven at 120° C. for drying, and the homemade cobalt powder is completed.

2. The method according to claim 1, characterized in that: The release agent in step 1 is lithium bromide.

3. The method according to claim 1, characterized in that: The melting sample setting mode described in step 2 includes: a first heat time of 60 seconds, the temperature reaches 800°C; a second heat time of 120 seconds, the temperature reaches 1020°C; after the temperature reaches 1020°C, melting for 240 seconds; a self-cooling time of 120 seconds, a wind cooling time of 120 seconds, and 4 swing speeds.

4. The method according to claim 1, characterized in that: The prepared cobalt powder is stored in a desiccator. If the storage period exceeds one month, it needs to be dried again before use.

5. Cobalt powder obtained by the method according to any one of claims 1 to 4.

6. Use of the cobalt powder as claimed in claim 5 in fluorescence analysis of iron ore.

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