Method for determining content of boron element in ferroboron

Abstract

The invention discloses a method for determining the content of boron element in ferroboron, which specifically comprises the following steps: respectively placing pure iron and ferroboron test samples in a quartz conical flask, adding aqua regia, after a violent reaction is stopped, adding a small amount of sulfuric acid, heating until sulfuric acid smoke is generated, covering a watch glass, keeping the temperature for 20-40 minutes, cooling, adding diluted hydrochloric acid, boiling and dissolving salts, transferring into a 250mL volumetric flask, and measuring the content of boron element in ferroboron. Fixing the volume with water, and shaking uniformly; further diluting and fixing the volume to obtain pure iron and ferroboron to-be-tested liquid; sequentially adding an acetic acid-sulfuric acid solution, a curcumin solution and an acetic acid-sodium acetate buffer solution into the pure iron and ferroboron to-be-tested solution; and measuring the absorbance of the pure iron and ferroboron test solution by adopting a spectrophotometer and taking water as a reference, obtaining the mass concentration of the pure iron and ferroboron test solution through a working curve, and further calculating the content of the boron element in ferroboron. The method provided by the invention solves the problem of determination of boron element in ferroboron, and has the advantages of high sensitivity, simple operation and good selectivity.

Description

Technical Field

[0001] The invention belongs to the technical field of metallurgical analysis and detection, and specifically relates to a method for determining the content of boron element in ferroboron. Background Art

[0002] Ferroboron is often used as a strong deoxidizer and boron additive in the steelmaking process. The boron content in steel is usually 0.0005%-0.01%. Boron can significantly improve the hardenability, mechanical strength and weldability of steel materials, and can also increase the high temperature strength, hardness and creep strength of the material; at the same time, ferroboron is also an important raw material for amorphous alloys and NdFeB permanent magnet materials. The boron content in ferroboron has a direct impact on the performance and quality of the product, so it is very important to accurately and quickly determine the boron content in ferroboron.

[0003] The standard detection method for determining the boron element in ferroboron in the prior art, GB / T 3653.1-1988, is an alkali titration method, which uses acid-base neutralization titration after high-temperature alkali melting, and the operation is complicated; the literature reports more about the use of inductively coupled plasma atomic emission spectrometry (ICP-AES) to determine the ferroboron content, but ICP-AES is not stable enough in determining high-content elements. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method for rapid determination of boron element in ferroboron, which has not only high sensitivity and high accuracy, but also simple instrument operation and wide application range, thereby improving the applicability of the analytical method and the convenience of operation.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A method for determining the content of boron in ferroboron comprises the following steps:

[0007] (1) Weigh 0.1g of pure iron and ferroboron samples respectively, place them in different quartz conical bottles, then add 10-15mL of aqua regia to each of them, and after the violent reaction stops, add 5-10mL of sulfuric acid, heat until sulfuric acid smoke appears, cover with a watch glass, keep warm for 20min-40min, cool, add dilute hydrochloric acid to boil and dissolve the salts, then transfer to a 250mL volumetric flask, dilute to volume with water, and shake well; transfer 5mL of the above test solution to a 50mL volumetric flask, dilute to volume with water, and shake well to obtain pure iron and ferroboron test solutions;

[0008] (2) Pipette 1 mL of pure iron and boron iron test solution into different containers, then add 5-10 mL of acetic acid-sulfuric acid solution and 4-6 mL of curcumin solution, respectively, let stand for 1 h to 2 h, then add 30 mL of acetic acid-sodium acetate buffer solution, mix well, and let stand for 15 min to 20 min;

[0009] (3) Using a spectrophotometer and water as a reference, the absorbance of pure iron and ferroboron test solutions was measured at a wavelength of 500-580 nm. The mass concentration of boron in the pure iron and ferroboron samples was obtained through the boron element working curve, and then the boron content in the ferroboron was obtained.

[0010] Furthermore, the method for drawing the boron element working curve of the present invention comprises the following steps:

[0011] 1) Pipette 0mL, 5.00mL, 10.00mL, 15.00mL, 20.00mL and 25.00mL of 1000μg / mL boron standard solution into 6 quartz conical flasks respectively, then add 10mL-15mL aqua regia into each flask, after the violent reaction stops, add 5-10mL sulfuric acid, heat until sulfuric acid smoke appears, cover with a watch glass, keep warm for 20min-40min, cool, add dilute hydrochloric acid to boil and dissolve salts, then transfer to a 250mL volumetric flask, dilute to volume with water, and shake well; Pipette 5mL of the above test solution into a 50mL volumetric flask, dilute to volume with water, and shake well to obtain boron standard solutions of different concentrations;

[0012] 2) Pipette 1 mL of different concentrations of boron standard solution into different containers, then add 5 mL to 10 mL of acetic acid-sulfuric acid solution and 4 mL to 6 mL of curcumin solution respectively, let stand for 1 h to 2 h, then add 30 mL of acetic acid-sodium acetate buffer solution, mix well, and let stand for 15 min to 20 min;

[0013] 3) Use a spectrophotometer and water as a reference to measure the absorbance of standard solutions of boron element with different concentrations at wavelengths of 500nm to 580nm. Draw a working curve with the mass concentration of boron as the horizontal axis and the absorbance as the vertical axis.

[0014] Furthermore, the mass concentration of the dilute hydrochloric acid in the present invention is 10% to 15%.

[0015] Furthermore, the amount of dilute hydrochloric acid added in the present invention is 10 mL to 20 mL.

[0016] The concentration of the boron standard solution used in the boron element working curve of the present invention is 2 μg / mL to 10 μg / mL, and the detection range of the boron element in ferroboron is 5% to 25%.

[0017] Furthermore, the calculation formula for the boron content in the ferroboron of the present invention is as follows:

[0018]

[0019] Where:

[0020] ω B——The content of boron in the ferroboron sample, in %;

[0021] C 1 ——The mass concentration of boron in the ferroboron sample, in micrograms per milliliter (μg / mL);

[0022] C 0 ——The mass concentration of boron in the pure iron sample, in micrograms per milliliter (μg / mL);

[0023] m – the mass of the sample, in grams (g).

[0024] The beneficial technical effects of the technical solution of the present invention are:

[0025] The present invention adopts spectrophotometry for testing, which has the advantages of high sensitivity, good selectivity, high accuracy, wide applicable concentration range, low analysis cost, simple and fast operation, and can be used as a conventional method for analyzing and testing the boron content in ferroboron. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The working curve of Example 1

[0027] Figure 2 The working curve of Example 2

[0028] Figure 3 The working curve of Example 3 DETAILED DESCRIPTION

[0029] The present invention will be further described in detail below in conjunction with specific embodiments.

[0030] The standard curve drawing method used in each embodiment is as follows:

[0031] Example 1

[0032] The method for determining the content of boron in ferroboron in the present embodiment comprises the following steps:

[0033] (1) Draw the working curve

[0034] Pipette 0mL, 5.00mL, 10.00mL, 15.00mL, 20.00mL and 25.00mL of 1000μg / mL boron standard solution into 6 quartz conical bottles respectively, then add 10mL of aqua regia into each of them, after the violent reaction stops, add 5mL of sulfuric acid, heat until sulfuric acid smoke appears, cover with a watch glass, keep warm for 30min and then cool, add 10mL of 15% hydrochloric acid to boil and dissolve the salts, then transfer to a 250mL volumetric flask, dilute to volume with water and shake well; Pipette 5mL of the above test solution into a 50mL volumetric flask, dilute to volume with water and shake well to obtain boron standard solutions of different concentrations;

[0035] Pipette 1 mL of different concentrations of boron standard solution into different containers, then add 5 mL of acetic acid-sulfuric acid solution and 4 mL of curcumin solution respectively, let stand for 1 hour, then add 30 mL of acetic acid-sodium acetate buffer solution, mix well, and let stand for 15 minutes;

[0036] A spectrophotometer was used, with water as the reference, to measure the absorbance at 520 nm, and a working curve was drawn with the mass concentration of boron as the horizontal axis and the absorbance as the vertical axis, as shown in the figure. Figure 1 shown.

[0037] (2) Sample concentration determination

[0038] Weigh 0.1g of pure iron and ferroboron samples respectively, accurate to 0.0001g, place the samples in a 200mL quartz conical flask, add 10mL of aqua regia respectively, add 5mL of sulfuric acid after the violent reaction stops, heat until sulfuric acid smoke appears, cover with a watch glass, keep warm for 30min and then cool, add 10mL of 15% hydrochloric acid to boil and dissolve the salts, transfer to a 250mL volumetric flask, dilute with water and shake well; transfer 5mL of the above test solution to a 50mL volumetric flask, dilute with water and shake well to obtain pure iron and ferroboron test solutions;

[0039] Pipette 1 mL of pure iron and boron iron test solution into different containers, then add 5 mL of acetic acid-sulfuric acid solution and 4 mL of curcumin solution respectively, let stand for 1 hour, then add 30 mL of acetic acid-sodium acetate buffer solution, mix well, and let stand for 15 minutes;

[0040] The absorbance was measured at 520 nm using a spectrophotometer with water as a reference, and the mass concentration of the boron element in the pure iron and ferroboron samples was obtained through the boron element working curve.

[0041] (3) Calculation of boron content in ferroboron

[0042] The calculation formula for the content of boron in ferroboron is as follows:

[0043]

[0044] Where:

[0045] ω B ——The content of boron in the ferroboron sample, in %;

[0046] C 1 ——The mass concentration of boron in the ferroboron sample, in micrograms per milliliter (μg / mL);

[0047] C 0 ——The mass concentration of boron in the pure iron sample, in micrograms per milliliter (μg / mL);

[0048] m – the mass of the sample, in grams (g).

[0049] According to calculation, the mass content of boron in the ferroboron sample of this embodiment is 17.62%.

[0050] The boron content in the ferroboron sample of this embodiment was measured by standard alkaline titration method, and the result was 17.54%, which was less than the repeatability limit requirement in GB / T3653.1-2024.

[0051] Example 2

[0052] The method for determining the content of boron in ferroboron in the present embodiment comprises the following steps:

[0053] (1) Draw the working curve

[0054] Pipette 0mL, 5.00mL, 10.00mL, 15.00mL, 20.00mL and 25.00mL of 1000μg / mL boron standard solution into 6 quartz conical bottles respectively, then add 15mL of aqua regia thereto respectively, after the violent reaction stops, add 6mL of sulfuric acid, heat until sulfuric acid smoke appears, cover with a watch glass, keep warm for 40min and then cool, add 15mL of 12% hydrochloric acid to boil and dissolve the salts, then transfer to a 250mL volumetric flask, dilute to volume with water and shake well; Pipette 5mL of the above test solution into a 50mL volumetric flask, dilute to volume with water and shake well to obtain boron standard solutions of different concentrations;

[0055] Pipette 1 mL of different concentrations of boron standard solution into different containers, then add 10 mL of acetic acid-sulfuric acid solution and 6 mL of curcumin solution respectively, let stand for 1 hour, then add 30 mL of acetic acid-sodium acetate buffer solution, mix well, and let stand for 15 minutes;

[0056] A spectrophotometer was used, with water as reference, to measure the absorbance at 550 nm, and a working curve was drawn with the mass concentration of boron as the horizontal axis and the absorbance as the vertical axis, as shown in the figure. Figure 2 shown.

[0057] (2) Sample concentration determination

[0058] Weigh 0.1g of pure iron and ferroboron samples respectively, accurate to 0.0001g, place the samples in a 200mL quartz conical flask, add 15mL of aqua regia respectively, add 6mL of sulfuric acid after the violent reaction stops, heat until sulfuric acid smoke appears, cover with a watch glass, keep warm for 40min and then cool, add 15mL of 12% hydrochloric acid to boil and dissolve the salts, transfer to a 250mL volumetric flask, dilute with water and shake well; transfer 5mL of the above test solution to a 50mL volumetric flask, dilute with water and shake well to obtain pure iron and ferroboron test solutions;

[0059] Pipette 1 mL of pure iron and boron iron test solution into different containers, then add 10 mL of acetic acid-sulfuric acid solution and 6 mL of curcumin solution, respectively, let stand for 1 hour, then add 30 mL of acetic acid-sodium acetate buffer solution, mix well, and let stand for 15 minutes;

[0060] The absorbance was measured at 550 nm using a spectrophotometer with water as a reference, and the mass concentration of the boron element in the pure iron and ferroboron samples was obtained through the boron element working curve.

[0061] (3) Calculation of analysis results:

[0062] The calculation formula for the content of boron in ferroboron is as follows:

[0063]

[0064] Where:

[0065] ω B ——The content of boron in the ferroboron sample, in %;

[0066] C 1 ——The mass concentration of boron in the ferroboron sample, in micrograms per milliliter (μg / mL);

[0067] C 0 ——The mass concentration of boron in the pure iron sample, in micrograms per milliliter (μg / mL);

[0068] m – the mass of the sample, in grams (g).

[0069] According to calculation, the mass content of boron in the ferroboron sample of this embodiment is 20.60%.

[0070] The boron content in the ferroboron sample of this embodiment was determined by standard alkaline titration method, and the result was 20.79%, which was less than the repeatability limit requirement in GB / T3653.1-2024.

[0071] Example 3

[0072] The method for determining the content of boron in ferroboron in the present embodiment comprises the following steps:

[0073] (1) Drawing working curve

[0074] Pipette 0mL, 5.00mL, 10.00mL, 15.00mL, 20.00mL and 25.00mL of 1000μg / mL boron standard solution into 6 quartz conical bottles respectively, then add 12mL of aqua regia into each bottle, after the violent reaction stops, add 10mL of sulfuric acid, heat until sulfuric acid smoke appears, cover with a watch glass, keep warm for 20min and then cool, add 20mL of 10% hydrochloric acid to boil and dissolve the salts, then transfer to a 250mL volumetric flask, dilute to volume with water and shake well; Pipette 5mL of the above test solution into a 50mL volumetric flask, dilute to volume with water and shake well to obtain boron standard solutions of different concentrations;

[0075] A spectrophotometer was used, with water as reference, to measure the absorbance at 550 nm, and a working curve was drawn with the mass concentration of boron as the horizontal axis and the absorbance as the vertical axis, as shown in the figure. Figure 3 shown.

[0076] (2) Sample concentration determination

[0077] Weigh 0.1g of pure iron and ferroboron samples respectively, accurate to 0.0001g, place the samples in a 200mL quartz conical flask, add 12mL of aqua regia respectively, add 10mL of sulfuric acid after the violent reaction stops, heat until sulfuric acid smoke appears, cover with a watch glass, keep warm for 20min, cool, add 20mL of 10% hydrochloric acid to boil and dissolve the salts, transfer to a 250mL volumetric flask, dilute with water, and shake well; transfer 5mL of the above test solution to a 50mL volumetric flask, dilute with water, and shake well to obtain pure iron and ferroboron test solutions;

[0078] 1 mL of pure iron and boron iron test solution were transferred to different containers, and then 8 mL of acetic acid-sulfuric acid solution and 5 mL of curcumin solution were added thereto respectively. After standing for 1.5 h, 30 mL of acetic acid-sodium acetate buffer solution was added, mixed, and allowed to stand for 20 min.

[0079] The absorbance was measured at 550 nm using a spectrophotometer with water as a reference, and the mass concentration of the boron element in the pure iron and ferroboron samples was obtained through the boron element working curve.

[0080] (3) Calculation of analysis results:

[0081] The calculation formula for the content of boron in ferroboron is as follows:

[0082]

[0083] Where:

[0084] ω B ——The content of boron in the ferroboron sample, in %;

[0085] C1 ——The mass concentration of boron in the ferroboron sample, in micrograms per milliliter (μg / mL);

[0086] C 0 ——The mass concentration of boron in the pure iron sample, in micrograms per milliliter (μg / mL);

[0087] m – the mass of the sample, in grams (g).

[0088] According to calculation, the mass content of boron in the ferroboron sample of this embodiment is 22.10%.

[0089] The boron content in the ferroboron sample of this embodiment was measured by standard alkaline titration method, and the result was 22.25%, which was less than the repeatability limit requirement in GB / T3653.1-2024.

[0090] It can be seen from the above experimental results that the method provided by the present invention can accurately determine the content of boron element in ferroboron and has good test precision and accuracy.

[0091] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for determining the content of boron in ferroboron, characterized in that: The following steps are involved: Place the pure iron and ferroboron test samples in a quartz conical flask, add aqua regia, and after the violent reaction stops, add a small amount of sulfuric acid, heat until sulfuric acid smoke appears, cover with a watch glass, keep warm for 20min to 40min, then cool, add dilute hydrochloric acid to boil and dissolve the salts, transfer to a 250mL volumetric flask, dilute with water, and shake well; transfer 5mL of the above test solution to a 50mL volumetric flask, dilute with water, and shake well to obtain the pure iron and ferroboron test solutions; Pipette 1 mL of pure iron and boron iron test solution into different containers, then add acetic acid-sulfuric acid solution and curcumin solution respectively, let stand for 1 h to 2 h, then add 30 mL of acetic acid-sodium acetate buffer solution, mix well, and let stand for 15 min to 20 min; (3) Using a spectrophotometer and water as a reference, the absorbance of pure iron and ferroboron test solutions was measured. The mass concentration of boron in the pure iron and ferroboron samples was obtained through the boron working curve, and then the boron content in ferroboron was obtained.

2. The method for determining the content of boron in ferroboron according to claim 1, characterized in that: In step (1), the test sample is weighed in an amount of 0.1 g, the amount of aqua regia added is 10 to 15 mL, and the amount of sulfuric acid added is 5 to 10 mL.

3. The method for determining the content of boron in ferroboron according to claim 1, characterized in that: In step (2), the amount of acetic acid-sulfuric acid solution added is 5-10 mL, and the amount of curcumin solution added is 4-6 mL.

4. The method for determining the content of boron in ferroboron according to claim 1, characterized in that: The absorbance measurement wavelength in step (3) is 500-580 nm.

5. The method for determining the content of boron in ferroboron according to claim 1, characterized in that: The method for drawing the boron element working curve in step (3) is as follows: Pipette 0mL, 5.00mL, 10.00mL, 15.00mL, 20.00mL and 25.00mL of 1000μg / mL boron standard solution into 6 quartz conical bottles respectively, then add 10mL-15mL aqua regia thereto respectively, after the violent reaction stops, add 5-10mL sulfuric acid, heat until sulfuric acid smoke appears, cover with a watch glass, keep warm for 20min-40min, then cool, add dilute hydrochloric acid to boil and dissolve the salts, then transfer to a 250mL volumetric flask, dilute to volume with water, and shake well; Pipette 5mL of the above test solution into a 50mL volumetric flask, dilute to volume with water, and shake well to obtain boron standard solutions of different concentrations; 2) Pipette 1 mL of different concentrations of boron standard solution into different containers, then add 5 mL to 10 mL of acetic acid-sulfuric acid solution and 4 mL to 6 mL of curcumin solution respectively, let stand for 1 h to 2 h, then add 30 mL of acetic acid-sodium acetate buffer solution, mix well, and let stand for 15 min to 20 min; 3) Use a spectrophotometer and water as a reference to measure the absorbance of standard solutions of boron element with different concentrations at wavelengths of 500nm to 580nm. Draw a working curve with the mass concentration of boron as the horizontal axis and the absorbance as the vertical axis.

6. The method for determining the content of boron in ferroboron according to claim 1, characterized in that: The mass concentration of the dilute hydrochloric acid is 10% to 15%.

7. The method for determining the content of boron in ferroboron according to claim 1, characterized in that: The amount of dilute hydrochloric acid added is 10 mL to 20 mL.

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