Method for simultaneously determining contents of multiple elements in silicon-manganese alloy

Abstract

The invention discloses a method for simultaneously determining the contents of multiple elements in a silicon-manganese alloy, which comprises the following steps: firstly, selecting 3-5 silicon-manganese alloy standard substances with known contents of silicon, manganese and phosphorus elements to form a concentration gradient, and crushing a sample to be detected and the selected standard substances into particles of less than 120 meshes; dissolving a to-be-detected sample and the selected standard substance in the solution; and then carrying out data acquisition on the emission spectrum light intensity of the standard substance silicon, manganese and phosphorus elements, drawing a standard working curve of each element according to the corresponding relationship between the element content and the emission spectrum light intensity, substituting the emission spectrum light intensity of the silicon, manganese and phosphorus elements of a sample to be detected, which is acquired by an instrument, into the standard working curve, and calculating the content of the silicon, manganese and phosphorus elements of the sample to be detected. The method solves the problem of sample solution preparation when the silicon-manganese alloy is determined by the ICP spectrometer, the sample solution preparation process is simple, and the determination process is not interfered.

Description

Technical Field

[0001] The invention relates to a method for simultaneously determining the contents of multiple elements in a silicon-manganese alloy, and belongs to the field of material analysis and testing. Background Art

[0002] Silicon manganese alloy is an alloy composed of silicon, manganese, iron, a small amount of carbon and other elements. It is a ferroalloy with a wide range of uses and a large output. Silicon manganese alloy is a commonly used composite deoxidizer in steelmaking, and a reducing agent for the production of medium and low carbon ferromanganese and the production of metallic manganese by the electric silicon thermal method. The traditional chemical composition analysis method is the chemical method, in which silicon is analyzed by weight, manganese by titration, and phosphorus by photometry. The disadvantage is that each element needs to be detected separately, the operation is cumbersome, the analysis process is lengthy, the amount of chemical reagents used is large, the analysis cost is high, and the accuracy is low.

[0003] Inductively coupled plasma (ICP-OES) emission spectrometry is the most commonly used analytical method for elemental analysis of metal materials. It has the advantages of low detection limit, high sensitivity, good stability, small matrix effect, wide linear range of concentration determination, and simultaneous determination of multiple elements, and has been widely used.

[0004] However, the traditional chemical sample pretreatment method requires the use of a variety of chemical reagents such as hydrochloric acid, nitric acid, sulfuric acid, perchloric acid, hydrofluoric acid, sodium nitrite, sodium arsenite, sodium hydroxide, etc. The addition of a large amount of chemical reagents to the test solution will interfere with the instrument test and affect the accuracy and repeatability of the measurement. Summary of the invention

[0005] The purpose of the present invention is to provide a method for determining the contents of silicon, manganese and phosphorus in a silicon-manganese alloy by ICP-OES method, which is fast, accurate and pollution-free to the instrument, so as to overcome the shortcomings of the prior art.

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] A method for simultaneously determining the contents of multiple elements in a silicon-manganese alloy of the present invention comprises the following steps:

[0008] 1) Selection of silicon-manganese alloy standard substances: Select 3-5 silicon-manganese alloy standard substances with known silicon 10.0%-30.0%, manganese 55.0%-70.0%, and phosphorus 0.05%-0.20% element contents to form a concentration gradient;

[0009] 2) Preparation method of solid samples: crush the sample to be tested and the selected silicon-manganese alloy standard material into particles smaller than 120 mesh for determination;

[0010] 3) Preparation of standard substance solution: weigh 0.1000-0.2000g of silicon-manganese alloy standard substance, place them in 50-100ml covered containers to which 1-2g potassium hydroxide has been added, add 3-4g sodium hydroxide, heat at 600-700℃ for not less than 30min, dissolve all the substances in the container in an appropriate amount of deionized water after cooling, mix with 10-20ml of 20%-50% hydrochloric acid aqueous solution and 20-30ml of 40%-60% nitric acid aqueous solution, add 5-20ml of 5%-20% sodium nitrite aqueous solution to the above solution, boil for not less than 3min, transfer to an appropriate volumetric flask after cooling, add 10-30ml of 40%-60% nitric acid aqueous solution, dilute quantitatively with deionized water, and mix well;

[0011] 4) Preparation of the sample solution to be tested: weigh 0.1000-0.2000g of the sample to be tested, and place them in a 50-100ml coverable container to which 1-2g potassium hydroxide has been added, and then add 3-4g sodium hydroxide, and heat at 600-700℃ for not less than 30min. After cooling, all the substances in the container are dissolved in an appropriate amount of deionized water, and mixed with 10-20ml of a 20%-50% hydrochloric acid aqueous solution and 20-30ml of a 40%-60% nitric acid aqueous solution by volume, and add 5-20ml of a 5%-20% sodium nitrite aqueous solution by mass to the above solution, boil for not less than 3min, and after cooling, transfer to an appropriate volumetric flask, add 10-30ml of a 40%-60% nitric acid aqueous solution by volume, and quantitatively dilute with deionized water, and mix well;

[0012] 5) Determination of samples to be tested: Data collection is performed on the emission spectrum intensity of silicon, manganese and phosphorus elements of silicon-manganese alloy standard materials, and the standard working curve of each element is drawn based on the corresponding relationship between the element content and the emission spectrum intensity. The emission spectrum intensity of silicon, manganese and phosphorus elements of the unknown content sample collected by the instrument is brought into the standard working curve to calculate the silicon, manganese and phosphorus content of the unknown content sample;

[0013] 6) Select certified reference materials to verify the accuracy of the test results of silicon, manganese and phosphorus contents.

[0014] The beneficial effects of the present invention are as follows: a method for simultaneously determining the contents of silicon, manganese and phosphorus in a silicon-manganese alloy by using an ICP-OES method which is fast, accurate and pollution-free to the instrument is provided; the present invention solves the problem of sample solution preparation when the silicon-manganese alloy is determined by an ICP spectrometer, the sample solution preparation process is simple, and no interference is generated in the determination process; the determination method of the present invention can be applied to sample pretreatment technology for determining the element content of silicon-manganese alloys by other element analysis instruments, and has broad application prospects in the field of material analysis. DETAILED DESCRIPTION

[0015] The present invention will be further described below in conjunction with the embodiments.

[0016] Example

[0017] 1) Select a series of standard substances with silicon contents of 11.10%, 16.35%, 22.89%, and 29.44%; manganese contents of 55.90%, 59.46%, 63.75%, and 69.35%; and phosphorus contents of 0.055%, 0.094%, 0.158%, and 0.191%;

[0018] 2) After the samples to be tested and the standard substances are crushed, particles smaller than 120 mesh are selected;

[0019] 3) Weigh 0.1600±0.0002g of a series of standard substances with different silicon, manganese and phosphorus content and place them in a 100ml nickel crucible with a cover to which 1.5g potassium hydroxide has been added, then add 3.0g of sodium hydroxide, cover and heat in an environment of 670±10℃ for 40min. After cooling, all the substances in the container are dissolved in deionized water, mixed with 13ml of hydrochloric acid aqueous solution (volume ratio concentration 30%) and 30ml of nitric acid aqueous solution (volume ratio concentration 50%), add 20ml of sodium nitrite aqueous solution (mass ratio concentration 5%) to the above solution, boil for 5min, cool and transfer to a 200ml volumetric flask, add 20ml of nitric acid aqueous solution (volume ratio concentration 40%), dilute quantitatively with deionized water and mix well;

[0020] 4) The preparation process of the sample solution with unknown content is the same as step 3);

[0021] 5) Using an inductively coupled plasma (ICP-OES) emission spectrometer, set the RF generator power to 1.5 kW, the atomization pressure to 25.0 psi, the argon flow rate to 0.8 L / min, the analysis pump speed to 2.50 ml / min, the sample flushing time to 70 s, the integration time to 30 s for short wave and 10 s for long wave; element analysis line (nm) silicon 251.611, manganese 257.610, phosphorus 213.618; collect data for a series of standard substances, draw standard working curves for each element, and determine the element content of the sample to be tested when the linear correlation coefficient of each curve is greater than 0.999;

[0022] 6) Select standard substances YSBC18603-08 and GSB03-1947-2005 to verify the accuracy of the test results of silicon, manganese, phosphorus and chromium content of the samples to be tested. The relative standard deviation RSD (%) is shown in the table below. As can be seen from the table, the RSD determined by this method is less than 2%. Compared with the standard value, the error of the determination result is within the allowable range of the national standard for chemical analysis.

[0023] Precision and accuracy (n=10)

[0024]

Claims

1. A method for simultaneously determining the content of multiple elements in a silicon-manganese alloy, characterized in that: The following steps are involved: 1) Selection of silicon-manganese alloy standard substances: Select 3-5 silicon-manganese alloy standard substances with known silicon 10.0%-30.0%, manganese 55.0%-70.0%, and phosphorus 0.05%-0.20% element contents to form a concentration gradient; 2) Preparation method of solid samples: crush the sample to be tested and the selected silicon-manganese alloy standard material into particles smaller than 120 mesh for determination; 3) Preparation of standard substance solution: weigh 0.1000-0.2000g of silicon-manganese alloy standard substance, place them in 50-100ml covered containers to which 1-2g potassium hydroxide has been added, add 3-4g sodium hydroxide, heat at 600-700℃ for not less than 30min, dissolve all the substances in the container in an appropriate amount of deionized water after cooling, mix with 10-20ml of 20%-50% hydrochloric acid aqueous solution and 20-30ml of 40%-60% nitric acid aqueous solution, add 5-20ml of 5%-20% sodium nitrite aqueous solution to the above solution, boil for not less than 3min, transfer to an appropriate volumetric flask after cooling, add 10-30ml of 40%-60% nitric acid aqueous solution, dilute quantitatively with deionized water, and mix well; 4) Preparation of the sample solution to be tested: weigh 0.1000-0.2000g of the sample to be tested, and place them in a 50-100ml coverable container to which 1-2g potassium hydroxide has been added, and then add 3-4g sodium hydroxide, and heat at 600-700℃ for not less than 30min. After cooling, all the substances in the container are dissolved in an appropriate amount of deionized water, and mixed with 10-20ml of a 20%-50% hydrochloric acid aqueous solution and 20-30ml of a 40%-60% nitric acid aqueous solution by volume, and add 5-20ml of a 5%-20% sodium nitrite aqueous solution by mass to the above solution, boil for not less than 3min, and after cooling, transfer to an appropriate volumetric flask, add 10-30ml of a 40%-60% nitric acid aqueous solution by volume, and quantitatively dilute with deionized water, and mix well; 5) Determination of samples to be tested: Data collection is performed on the emission spectrum intensity of silicon, manganese and phosphorus elements of silicon-manganese alloy standard materials, and the standard working curve of each element is drawn based on the corresponding relationship between the element content and the emission spectrum intensity. The emission spectrum intensity of silicon, manganese and phosphorus elements of the unknown content sample collected by the instrument is brought into the standard working curve to calculate the silicon, manganese and phosphorus content of the unknown content sample; 6) Select certified reference materials to verify the accuracy of the test results of silicon, manganese and phosphorus contents.

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