Method for measuring chromium in high-carbon ferro-chrome by X-ray fluorescence spectrophotometer

Abstract

The invention relates to the technical field of detection, in particular to a method for measuring chromium in high-carbon ferro-chrome by an X-ray fluorescence spectrophotometer, which specifically comprises the following steps: S1, sample requirements: the granularity of a high-carbon ferro-chrome sample is greater than 180 meshes, and the high-carbon ferro-chrome sample is uniformly dried; s2, preparation of a sample glass sheet: weighing pure lithium tetraborate, pouring the pure lithium tetraborate into a platinum crucible, paving the bottom flatly with the periphery slightly higher, and forming a bowl shape for later use; weighing a high-carbon ferro-chrome sample and a high-carbon ferro-chrome oxidizing agent, uniformly mixing in the porcelain crucible, and completely pouring into the central position of lithium tetraborate in the platinum crucible; weighing a mixed reagent of lithium tetraborate and lithium metaborate, covering the surface of the mixture with the mixed reagent, adding lithium bromide, putting the mixture into a full-automatic sample melting machine, and melting to prepare a glass sheet; and S3, detecting the fluorescence excitation energy of the chromium element in the high-carbon ferro-chrome through an X-ray fluorescence spectrometry to analyze the element content. The method is short in detection period, high in accuracy, free of personal error, free of material consumption, simple and easy to operate, free of pollutant emission, environment-friendly and safe.

Description

Technical Field

[0001] The invention belongs to the field of detection technology, and in particular relates to a method for determining chromium in high-carbon ferrochrome using an X-ray fluorescence spectrometer. Background Art

[0002] High-carbon ferrochrome is a crucial raw material for steelmaking, directly impacting steel quality. However, chemical analysis of high-carbon ferrochrome involves acid decomposition or alkali dissolution of the sample, followed by oxidation with ammonium persulfate using silver nitrate as a catalyst to oxidize the chromium to its high valence. Sodium chloride is added, and the permanganate is boiled to destroy it, reducing the manganese to its divalent state. Titration is then performed using a standard solution of ferrous ammonium sulfate. This analysis process is long, typically exceeding five hours, resulting in wasteful labor, material, and financial resources, the use of large quantities of chemicals, and environmental pollution. This has become a pressing issue for steel companies in recent years.

[0003] Existing patent CN103149074B discloses a method for preparing chromium-iron glass frits, which includes the following steps: a. Accurately weigh 2 parts by weight of lithium tetraborate, 1 part by weight of lithium carbonate, 0.5 parts by weight of an oxidant, and 0.1 parts by weight of a sample, mix them evenly, and wrap them into balls; the sample is ferromolybdenum, ferromanganese, ferrovanadium, ferrochrome, or metallic manganese; b. Place the material wrapped into balls in step a into a crucible lined with graphite powder, and then place it in a high-temperature furnace for melting and pre-oxidation; remove the crucible, cool it, and obtain a pre-oxidized molten ball. This method requires wrapping into balls after weighing multiple times, and careless operation can easily cause material loss. The pre-oxidation process requires the use of a high-temperature furnace, which is cumbersome and time-consuming. The oxidized balls are sticky with carbon powder. If not cleaned properly, they will corrode the precious platinum crucible at high temperatures. This melting method requires high human involvement during the melting process, and human factors can cause large detection errors. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for determining chromium in high-carbon ferrochrome using an X-ray fluorescence spectrometer. This method can quickly, stably and accurately detect the chromium content in high-carbon ferrochrome, achieving the effects of a short detection cycle, no human error, simple and easy operation, no pollutant emissions, and environmental safety.

[0005] To achieve the above objectives, the present invention adopts the following technical solutions:

[0006] A method for determining chromium in high-carbon ferrochrome using an X-ray fluorescence spectrometer, comprising the following steps:

[0007] S1. Sample requirements

[0008] The particle size of high carbon ferrochrome samples is larger than 180 mesh and is dried evenly;

[0009] S2. Sample glass slide preparation

[0010] Weigh pure lithium tetraborate and pour it into a platinum crucible, flatten the bottom and slightly raise the sides to form a bowl shape, and set aside;

[0011] Weigh high carbon ferrochrome sample and high carbon ferrochrome oxidant, mix them in a porcelain crucible, and pour them all into the center of lithium tetraborate in a platinum crucible;

[0012] Weigh a mixture of lithium tetraborate and lithium metaborate and cover the surface of the mixture, add lithium bromide, and place the mixture in an automatic melting machine to melt the sample into a glass sheet;

[0013] S3. Analyze the element content by detecting the fluorescence excitation energy of chromium in high carbon ferrochrome using X-ray fluorescence spectrometry

[0014] The glass slide is placed in an X-ray fluorescence spectrometer, different X-ray fluorescence excitation conditions and detection conditions are set on the X-ray fluorescence spectrometer, and the sample is irradiated with X-rays;

[0015] The intensity of chromium in high-carbon ferrochrome is obtained by using the fluorescence excitation energy generated by chromium in a glass piece irradiated by X-rays in an X-ray fluorescence spectrometer. The X-ray fluorescence intensity of chromium is related to its content. The content of the unknown sample is obtained by comparing the measured intensity with the X-ray fluorescence intensity of the same element and the same spectral line of the standard substance.

[0016] In step 2, the mass ratio of the high carbon ferrochrome sample, the high carbon ferrochrome oxidant, the pure lithium tetraborate, the lithium tetraborate and the lithium metaborate mixed reagent is 1:(12-15):(35-40):(10-15);

[0017] In step 2, the mixed reagent of lithium tetraborate and lithium metaborate: the mass ratio of lithium tetraborate to lithium metaborate (67-70):

[0018] (25-33).

[0019] In step 2, the high carbon ferrochrome oxidant is prepared by mixing potassium nitrate, barium peroxide and boron trioxide in a mass ratio of 1:(7-10):(2-5).

[0020] The concentration of lithium bromide in step 2 is 50%.

[0021] Compared with the existing technology, the beneficial effects of the present invention are:

[0022] Compared with the ammonium persulfate redox titration chemical analysis method for determining the chromium content in high-carbon ferrochrome, the detection method of the present invention shortens the detection cycle from 5 hours to 1.5 hours. The present invention has a short detection cycle, high accuracy, no human error, no material consumption, simple and easy operation, no pollutant emissions, and is environmentally safe. DETAILED DESCRIPTION

[0023] It should be noted that, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein in the specification of the application are for the purpose of describing specific embodiments only and are not intended to limit this application. Mentioning "embodiments" herein means that the specific features, structures or characteristics described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention.

[0024] A method for determining chromium in high-carbon ferrochrome using an X-ray fluorescence spectrometer, comprising the following steps:

[0025] S1. Sample requirements

[0026] The particle size of high carbon ferrochrome samples is larger than 180 mesh and is dried evenly;

[0027] S2. Sample glass slide preparation

[0028] Weigh pure lithium tetraborate and pour it into a platinum crucible, flatten the bottom and slightly raise the sides to form a bowl shape, and set aside;

[0029] A high-carbon ferrochrome oxidant and a high-carbon ferrochrome sample are weighed, mixed evenly in a porcelain crucible, and poured into the center of lithium tetraborate in a platinum crucible; the high-carbon ferrochrome oxidant is prepared by mixing potassium nitrate, barium peroxide, and boron trioxide in a mass ratio of 1:(7-10):(2-5).

[0030] Weigh lithium tetraborate and lithium metaborate mixed reagent and cover the surface of the above mixture, the mass ratio of high carbon ferrochrome sample, high carbon ferrochrome oxidizer, pure lithium tetraborate, lithium tetraborate and lithium metaborate mixed reagent is 1:(12-15):(35-40):(10-15);

[0031] Mixed reagent of lithium tetraborate and lithium metaborate: the mass ratio of lithium tetraborate to lithium metaborate is (67-70):(25-33).

[0032] Add 0.5-1.0 ml of 50% lithium bromide and place the sample in a fully automatic melting machine to melt the sample into a glass sheet;

[0033] S3. Analyze the element content by detecting the fluorescence excitation energy of chromium in high carbon ferrochrome using X-ray fluorescence spectrometry

[0034] The glass slide is placed in an X-ray fluorescence spectrometer, different X-ray fluorescence excitation conditions and detection conditions are set on the X-ray fluorescence spectrometer, and the sample is irradiated with X-rays;

[0035] The intensity of chromium in high-carbon ferrochrome is obtained by using the fluorescence excitation energy generated by chromium in a glass piece irradiated by X-rays in an X-ray fluorescence spectrometer. The X-ray fluorescence intensity of chromium is related to its content. The content of the unknown sample is obtained by comparing the measured intensity with the X-ray fluorescence intensity of the same element and the same spectral line of the standard substance.

[0036] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0037] Example:

[0038] A method for determining chromium in high-carbon ferrochrome using an X-ray fluorescence spectrometer, comprising the following steps:

[0039] S1. Sample requirements

[0040] The particle size of high carbon ferrochrome samples is larger than 180 mesh and is dry and uniform.

[0041] S2. Sample glass slide preparation

[0042] Accurately weigh 7 grams of pure lithium tetraborate and pour it into a platinum crucible, flatten the bottom and slightly raise the edges to form a bowl shape, and set aside.

[0043] Accurately weigh 2.5 g of high-carbon ferrochrome oxidizer (barium peroxide, potassium nitrate, and boron trioxide mixed in a ratio of 7:1:2); 0.2 g of high-carbon ferrochrome sample, mix them evenly in a 30 ml porcelain crucible, pour all into the center of the lithium tetraborate in a platinum crucible, and clean it up.

[0044] Accurately weigh 2 grams of lithium tetraborate and lithium metaborate mixed reagents to cover the mixture, with the mass ratio of lithium tetraborate to lithium metaborate being 67:33, and add 0.5 ml of 50% lithium bromide, and place it in the fully automatic melting machine.

[0045] Select the high carbon ferrochrome mode on the fully automatic melting machine, and the melting conditions are shown in Table 1;

[0046] Table 1:

[0047]

[0048] Click the "Start Melting Sample" button to enter the melting sample process. When the melting sample is completed, click the "Stop Melting Sample" button to end the melting sample and obtain the glass sheet.

[0049] S3. Analyze the element content by detecting the fluorescence excitation energy of chromium in high carbon ferrochrome using X-ray fluorescence spectrometry

[0050] The molten glass piece is placed in an X-ray fluorescence spectrometer, different X-ray fluorescence excitation conditions and detection conditions are set on the X-ray fluorescence spectrometer, and the glass piece is irradiated with X-rays;

[0051] The intensity of chromium in high-carbon ferrochrome is obtained by using the fluorescence excitation energy generated by chromium in a glass piece irradiated by X-rays in an X-ray fluorescence spectrometer. The X-ray fluorescence intensity of chromium is related to its content. The content of the unknown sample is obtained by comparing the measured intensity with the X-ray fluorescence intensity of the same element and the same spectral line of the standard substance.

[0052] The comparison of the chromium test results in high carbon ferrochrome and the chemical analysis method is shown in Table 2;

[0053] Table 2:

[0054]

[0055] The t-test method was used for evaluation. As shown in Table 2, the statistical results show that chromium t 统计 <t 临界 , indicating that there is no systematic difference between the determination results of the method of the present invention and the chemical analysis method, indicating that the method of the present invention is accurate and reliable.

[0056] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and basic spirit of the invention, and the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for determining chromium in high carbon ferrochrome using an X-ray fluorescence spectrometer, characterized in that: The specific steps include: S1. Sample requirements The particle size of high carbon ferrochrome samples is larger than 180 mesh and is dried evenly; S2. Sample glass slide preparation Weigh pure lithium tetraborate and pour it into a platinum crucible, flatten the bottom and slightly raise the sides to form a bowl shape, and set aside; Weigh high carbon ferrochrome sample and high carbon ferrochrome oxidant, mix them in a porcelain crucible, and pour them all into the center of lithium tetraborate in a platinum crucible; Weigh a mixture of lithium tetraborate and lithium metaborate and cover the surface of the mixture, add lithium bromide, and place the mixture in an automatic melting machine to melt the sample into a glass sheet; S3. Analyze the element content by detecting the fluorescence excitation energy of chromium in high carbon ferrochrome using X-ray fluorescence spectrometry The glass slide is placed in an X-ray fluorescence spectrometer, different X-ray fluorescence excitation conditions and detection conditions are set on the X-ray fluorescence spectrometer, and the sample is irradiated with X-rays; The intensity of chromium in high-carbon ferrochrome is obtained by using the fluorescence excitation energy generated by chromium in a glass piece irradiated by X-rays in an X-ray fluorescence spectrometer. The X-ray fluorescence intensity of chromium is related to its content. The content of the unknown sample is obtained by comparing the measured intensity with the X-ray fluorescence intensity of the same element and the same spectral line of the standard substance.

2. The method for determining chromium in high carbon ferrochrome by X-ray fluorescence spectrometer according to claim 1, characterized in that: In step 2, the mass ratio of the high carbon ferrochrome sample, the high carbon ferrochrome oxidant, the pure lithium tetraborate, and the mixed reagent of lithium tetraborate and lithium metaborate is 1:(12-15):(35-40):(10-15).

3. The method for determining chromium in high carbon ferrochrome by X-ray fluorescence spectrometer according to claim 1, characterized in that: In step 2, the mixed reagent of lithium tetraborate and lithium metaborate is as follows: the mass ratio of lithium tetraborate to lithium metaborate is (67-70): (25-33).

4. The method for determining chromium in high carbon ferrochrome by X-ray fluorescence spectrometer according to claim 1, characterized in that: In step 2, the high carbon ferrochrome oxidant is prepared by mixing potassium nitrate, barium peroxide and boron trioxide in a mass ratio of 1:(7-10):(2-5).

5. The method for determining chromium in high carbon ferrochrome by X-ray fluorescence spectrometer according to claim 1, characterized in that: The concentration of lithium bromide in step 2 is 50%.

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