Method for determining cerium in cerium-iron alloy

Abstract

The invention discloses a method for determining cerium in cerium-iron alloy, which comprises the following steps: weighing a certain amount of sample, dissolving the sample with nitric acid-hydrochloric acid, transferring into a volumetric flask, fixing the volume, and shaking uniformly; atomizing the solution, introducing the atomized solution into an inductively coupled plasma atomic emission spectrometer, and measuring the signal intensity of the element to be measured; and finally, outputting the concentration of the corresponding element in the substance to be detected according to the working curve of the standard substance with known concentration. The invention aims to provide the method for determining cerium in the cerium-iron alloy, and the method is used for production practice and is an effective and practical method.

Description

Technical Field

[0001] The present invention belongs to the technical field of metallurgical analysis, and particularly relates to a method for determining cerium in ferrocerium alloy. Background Art

[0002] Ferrocerium alloy, as an intermediate alloy of rare earth cerium element and iron element, is mainly used as a rare earth additive for NdFeB permanent magnet materials or steel materials. It can purify molten steel, modify inclusions and refine the grain size of steel, thereby improving the strength, toughness, wear resistance, low-temperature impact flexibility and weldability of steel. With the increasingly wide application of NdFeB magnetic materials, the market demand for ferrocerium alloy is increasing. The rare earth content in rare earth alloy is used as a quality control index for downstream products and a pricing indicator for both trading parties. Therefore, it is of great significance to accurately and rapidly analyze the rare earth content. Conventional volumetric method and gravimetric method cannot accurately determine the content of each rare earth component or a single rare earth component in rare earth alloy. Based on the above situation, we have invented a method for determining cerium in ferrocerium alloy. Summary of the Invention

[0003] In order to accurately and rapidly determine the content of cerium element in ferrocerium alloy, the purpose of the present invention is to provide a method for determining cerium in ferrocerium alloy. This method has been used in production practice and is an effective and practical method.

[0004] To solve the above technical problems, the present invention adopts the following technical solutions:

[0005] A method for determining cerium in ferrocerium alloy of the present invention comprises weighing a certain amount of sample, dissolving the sample with nitric acid-hydrochloric acid, transferring it to a volumetric flask, fixing the volume and shaking well; atomizing the solution and introducing it into an inductively coupled plasma atomic emission spectrometer to measure the intensity of the signal of the element to be measured; finally, outputting the concentration of the corresponding element in the substance to be measured through the working curve of the standard substance with known concentration.

[0006] Furthermore, when the content exceeds 20%, it is diluted ten times by liquid separation.

[0007] Furthermore, the inductively coupled plasma atomic emission spectrometer is OPTIMA 5300DV bidirectional observation type full-spectrum direct-reading plasma spectrometer produced by PE Company of the United States.

[0008] Furthermore, the working parameter table of this instrument is as follows:

[0009]

[0010] Further, weigh 0.1000 g of the test sample, accurate to 0.0002 g; place the weighed sample in a 100 mL steel volumetric flask, add 20 mL of hydrochloric acid - nitric acid - water, heat and dissolve it on an electric hot plate until the sample is completely dissolved, dilute it to the mark with water and mix well, and measure this solution with an inductively coupled plasma spectrometer.

[0011] Further, add an equal amount of mixed acid to 5 100 mL volumetric flasks, then transfer the cerium standard solution to the volumetric flask as needed, dilute it to the mark with water and shake well, and draw a working curve according to the corresponding content value of cerium element.

[0012] Further, the determination range: Ce: 0.01% - 30%.

[0013] Compared with the prior art, the beneficial technical effects of the present invention are:

[0014] Accurately analyzing the content of cerium element in cerium-iron alloy is an important means to control product quality. For this reason, the present invention provides a method for determining cerium in cerium-iron alloy. This method has been used in production practice, and the determination results are accurate. It is an effective and practical method and can be popularized and applied in the metallurgical industry and related scientific research institutes. Specific Embodiments

[0015] A method for determining cerium in cerium-iron alloy, comprising:

[0016] 1 Scope

[0017] This method specifies the determination of cerium element content in cerium-iron alloy by inductively coupled plasma atomic emission spectrometry.

[0018] Determination range: Ce: 0.01% - 30%.

[0019] 2 Method Summary

[0020] Weigh a certain amount of the sample, dissolve the sample with nitric acid - hydrochloric acid, transfer it to a 100 mL volumetric flask, make it up to the mark and shake well. If the content exceeds 20%, it can be diluted ten times by liquid separation. Atomize the solution and introduce it into an inductively coupled plasma atomic emission spectrometer to measure the intensity of the signal of the element to be measured. Finally, through the working curve of the standard substance with known concentration, output the concentration of the corresponding element in the substance to be measured.

[0021] 3 Reagents and Materials

[0022] 3.1 Hydrochloric acid, ρ is about 1.19 g / mL;

[0023] 3.2 Nitric acid, ρ is about 1.42 g / mL;

[0024] 3.3 Cerium standard solution, 1000 μg / mL;

[0025] 4. Main Instruments and Test Conditions

[0026] 4.1 OPTIMA 5300DV bidirectional observation type full-spectrum direct-reading inductively coupled plasma spectrometer produced by PerkinElmer, USA.

[0027] 4.2 Instrument parameters: See the following table

[0028] Table of Operating Parameters

[0029]

[0030] 4.3 The analytical line wavelength of the element to be measured is: Cerium 418.66nm

[0031] 5 Analytical Procedures

[0032] 5.1 Sample Quantity

[0033] Weigh 0.1000g of the sample, accurate to 0.0002g.

[0034] 5.2 Determination Procedures

[0035] Place the weighed sample in a 100 mL steel volumetric flask, add 20 mL of hydrochloric acid-nitric acid-water (1+1+3), heat and dissolve it on an electric hot plate until the sample is completely dissolved, dilute it to the mark with water and mix well. This solution is determined by an inductively coupled plasma spectrometer.

[0036] Carry reagent blanks with each batch.

[0037] 5.3 Curve Plotting

[0038] Add an equal amount of mixed acid to 5 100 mL volumetric flasks, then transfer the cerium standard solution to the volumetric flasks as needed, dilute it to the mark with water and shake well. Draw a working curve according to the corresponding content values of cerium element.

[0039] 6 Results and Discussion

[0040] 6.1 Accuracy Experiment

[0041] Weigh the cerium-iron alloy sample and conduct a standard addition recovery experiment according to this method. The results are shown in Table 1:

[0042] Table 1 Accuracy of Determination Results (%)

[0043] Element to be measured Initial value Spiked amount Measured value Recovery rate Ce 20.05 5.00 25.17 102

[0044] It can be seen from the data in the table that the recovery rate of the standard addition experiment is between 95% and 110%. This analytical method has high accuracy.

[0045] 6.2 Precision Experiment

[0046] Weigh 11 samples of cerium-iron alloy and conduct precision tests according to the above experimental method. The test results are shown in Table 2:

[0047] Table 2 Precision Table of Determination Results (%)

[0048] Element to be measured Average value Standard deviation RSD Ce 20.05 0.16％ 0.80％

[0049] The above data indicate that the precision of this detection method is good.

[0050] 7 Conclusions

[0051] Through this method, the content of cerium in cerium-iron alloy can be accurately determined. This method is simple to operate and easy to master, and can meet the production requirements.

[0052] The embodiments described above are only for describing the preferred mode of the present invention and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solution of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for determining cerium in ferrocerium alloy, characterized in that: include: Weigh a certain amount of sample, dissolve it with nitric acid-hydrochloric acid, transfer it to a volumetric flask, and shake it up after making it equal to the volume; The solution is atomized and introduced into the inductively coupled plasma atomic emission spectrometer to measure the intensity of the signal of the element to be tested; finally, the concentration of the corresponding element in the substance to be tested is output through the working curve of the standard substance with known concentration.

2. The method for determining cerium in ferrocerium alloy according to claim 1, characterized in that: If the content exceeds 20%, it should be diluted ten times by liquid separation.

3. The method for determining cerium in ferrocerium alloy according to claim 1, characterized in that: The inductively coupled plasma atomic emission spectrometer is an OPTIMA 5300DV two-way observation full-spectrum direct-reading plasma spectrometer produced by PE Company of the United States.

4. The method for determining cerium in ferrocerium alloy according to claim 3, characterized in that: The instrument's operating parameters are shown below:

5. The method for determining cerium in ferrocerium alloy according to claim 1, characterized in that: Weigh 0.1000 g of the sample, accurate to 0.0002 g; place the weighed sample in a 100 mL steel volumetric flask, add 20 mL of hydrochloric acid-nitric acid-water, place on a hot plate to heat and dissolve until the sample is completely dissolved, dilute with water to the scale and mix well, and measure the solution using a plasma spectrometer.

6. The method for determining cerium in ferrocerium alloy according to claim 1, characterized in that: Add equal amounts of mixed acid to 5 100mL volumetric flasks, then transfer the cerium standard solution to the volumetric flask as needed, dilute with water to the scale and shake well, and draw a working curve based on the corresponding cerium content value.

7. The method for determining cerium in ferrocerium alloy according to claim 1, characterized in that: Measurement range: Ce: 0.01%~30%.

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