X-ray fluorescence spectrometric analysis of copper ore sample preparation and detection method

Abstract

The application relates to a preparation and detection method of copper ore samples by X-ray fluorescence spectrum analysis, wherein a coarse powder body of the ore is mixed with a binder and then grinded; a layer of boric acid is paved in a tablet pressing ring, the powder is uniformly paved on the boric acid, a tablet pressing machine is used for pressing, and a tablet sample is prepared; the binder is obtained by coordination of polyacrylic acid and polyvinyl alcohol europium nitrate. The sample prepared by using the common binder boric acid as a base and uniformly paving the prepared fine powder containing the binder thereon is more uniform and compact, the structure is solid, the surface is smooth and crack-free, and the sample is not dropped; the prepared tablet is directly tested by X-ray fluorescence spectrum analysis, the operation efficiency is high, the analysis data is reliable, the rare earth material is first applied to the X-ray fluorescence spectrum analysis of the copper ore, the fluorescence imaging is synergized, and the main peak is not disturbed; the direct tablet pressing saves the process of dissolution, reheating, cooling and solidification, the polyacrylic acid and polyvinyl alcohol serve as ligands and also play a binding role, and the compactness and integrity of the tablet are ensured.

Description

Technical Field

[0001] This invention relates to the field of mineral metal element analysis technology, specifically to a method for preparing and detecting copper ore samples using X-ray fluorescence spectroscopy. Background Technology

[0002] X-ray fluorescence spectrometry (XRF) is characterized by its simple sample preparation, convenient analysis, and high speed. Determining the content of various components in ores using XRF is of great significance for understanding the mining value of ores. Early XRF spectroscopy methods often used melt preparation of samples, which effectively eliminated particle effects, but the sample preparation process was complex and time-consuming. Currently, powder compression is widely used for sample preparation, which is low-cost, simple, and efficient. However, the sheet-like structure of powder compression is prone to loosening, affecting the detection results; therefore, binders are often needed to ensure the integrity of the compressed sample.

[0003] For example, invention patent CN103207197B discloses an X-ray fluorescence spectrometry method for analyzing the copper content in copper ore, and proposes a method for preparing analytical samples using a curing agent. However, this method still requires acid hydrolysis pretreatment to obtain crystalline salt, which is then dissolved, mixed, heated, and cooled to solidify into a thin sheet. This process is still time-consuming, and the curing agents used are agarose and konjac gum, which are susceptible to moisture and require high storage conditions. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method for preparing ore samples using a pelleting method and performing elemental quantitative analysis using an X-ray fluorescence spectrometer.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A method for preparing copper ore samples for X-ray fluorescence spectroscopy analysis includes the following steps:

[0007] S1. The ore raw material is crushed and ground to obtain coarse powder;

[0008] S2. Mix the coarse powder with 0.04~0.08wt% of binder and grind it again to refine and mix it into a fine powder.

[0009] S3. Spread a layer of boric acid in the compression ring, take fine powder and spread it evenly on the boric acid, and use a tablet press to compress it to obtain the product.

[0010] The preparation process of the adhesive is as follows:

[0011] Weigh polyacrylic acid and polyvinyl alcohol into a reaction flask, add 70% ethanol solution and stir to dissolve, then add europium nitrate hexahydrate, add ammonia water dropwise to adjust pH=7, heat to reflux at 70~90℃ for 2h, concentrate to obtain solid, dry and grind to obtain the final product.

[0012] Furthermore, the particle size of the fine powder is <200 mesh.

[0013] Furthermore, the pressure during the tableting process is 30-40t, the holding time is 30-50s, and the depressurization time is 10-15s.

[0014] Furthermore, the molecular weights of the polyacrylic acid and polyvinyl alcohol are both 1000-2000 g / mol, and the mass ratio of polyacrylic acid, polyvinyl alcohol and europium nitrate hexahydrate is 0.3~0.5:0.1:1.

[0015] The present invention further provides a method for detecting copper ore by X-ray fluorescence spectroscopy. The sample is prepared by the above preparation method, and then the elemental intensity of copper is obtained by full-spectrum X-ray fluorescence spectroscopy. The copper content in the sample is calculated by substituting it into the standard curve of the standard material.

[0016] The beneficial effects of this invention are as follows: After pulverizing the ore, a binder is added for further grinding and sieving. Boric acid, a commonly used binder, is used as a base layer to evenly spread the fine powder, resulting in a more uniform and dense sample with a solid structure, a smooth surface without cracks, and no slag shedding. The resulting tablet can be directly tested using X-ray fluorescence spectroscopy, resulting in high operational efficiency and reliable analytical data. This invention is the first to apply rare earth upconversion materials to the X-ray fluorescence spectroscopy analysis of copper ore, enhancing fluorescence imaging without interfering with the main peak. Direct tableting after ore grinding eliminates the need for dissolution, reheating, cooling, and solidification. The ligands, polyacrylic acid and polyvinyl alcohol, also act as binders, ensuring the tablet's compactness and integrity. Attached Figure Description

[0017] Figure 1 The copper content-strength standard working curve was established for this case. Detailed Implementation

[0018] The technical solution of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0020] Example 1: Sample Preparation

[0021] S1. The ore raw material is crushed and ground to obtain coarse powder;

[0022] S2. Mix the coarse powder with 0.05wt% binder and grind it again to refine and mix it into a fine powder.

[0023] S3. Spread a layer of boric acid in the compression ring, take fine powder and spread it evenly on the boric acid, and use a tablet press to compress it to obtain the product.

[0024] The preparation process of the adhesive is as follows:

[0025] Weigh 0.5g of polyacrylic acid and 0.1g of polyvinyl alcohol (both with a molecular weight of 1000) into a reaction flask, add 70% ethanol solution and stir to dissolve, then add 1g of europium nitrate hexahydrate, add ammonia water dropwise to adjust the pH to 7, heat to reflux at 70~90℃ for 2h, concentrate to obtain a solid, dry, and grind to obtain the final product.

[0026] The obtained sample has a smooth and clean surface without cracks.

[0027] Example 2: X-ray fluorescence spectroscopy analysis of copper content in copper ore

[0028] I. Establishing a Standard Curve

[0029] 1) The standard sample is determined by chemical method, and then it is made into a standard sample pellet that can be analyzed by X-ray fluorescence spectrometry;

[0030] 2) The standard sample pellet was analyzed using an X-ray fluorescence spectrometer. The average fluorescence intensity of each element was measured. A working curve was established based on the concentration and light intensity. The elements in the working curve were corrected using the empirical coefficient method. After fitting, the standard curve was generated as follows: Figure 1 As shown.

[0031] I =30.33·C-5.87(R 2 =0.998)

[0032] A copper ore sample was taken, and 10 sample pieces were prepared according to the method in Example 1 for measurement. The spectral intensity was recorded. I Substituting into the above formula, the copper content C% was calculated. The results are shown in Table 1. As can be seen from Table 1, the sample preparation method of the present invention using the above-mentioned tableting method has good reproducibility.

[0033] Table 1

[0034]

[0035] Copper ore samples with different copper contents were extracted, and sample pellets were prepared according to the sample preparation method in Example 1, denoted as Sample 1 to Sample 10. The spectral intensity was then... I Substituting into the above formula, the copper content C% was calculated, and the results are shown in Table 2.

[0036] Table 2

[0037]

[0038] As shown in Table 2, the values ​​determined by this method are close to those determined by the chemical method, with a small difference, and can be used for quantitative analysis of the content of copper ore powder.

[0039] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details.

Claims

1. A method for preparing copper ore samples for X-ray fluorescence spectrometry analysis, characterized in that, Includes the following steps: S1. The ore raw material is crushed and ground to obtain coarse powder; S2. Mix the coarse powder with 0.04~0.08wt% of binder and grind it again to refine and mix it into a fine powder. S3. Spread a layer of boric acid in the compression ring, take fine powder and spread it evenly on the boric acid, and use a tablet press to compress it to obtain the product. The preparation process of the adhesive is as follows: Weigh polyacrylic acid and polyvinyl alcohol into a reaction flask, add 70% ethanol solution and stir to dissolve, then add europium nitrate hexahydrate, add ammonia water dropwise to adjust pH=7, heat to reflux at 70~90℃ for 2h, concentrate to obtain solid, dry and grind to obtain the final product.

2. The method for preparing copper ore samples for X-ray fluorescence spectrometry analysis according to claim 1, characterized in that, The fine powder has a particle size of <200 mesh.

3. The method for preparing copper ore samples for X-ray fluorescence spectrometry analysis according to claim 1, characterized in that, The pressure during the tableting process is 30-40t, the holding time is 30-50s, and the depressurization time is 10-15s.

4. The method for preparing copper ore samples for X-ray fluorescence spectrometry analysis according to claim 1, characterized in that, The molecular weights of the polyacrylic acid and polyvinyl alcohol are both 1000-2000 g / mol, and the mass ratio of polyacrylic acid, polyvinyl alcohol and europium nitrate hexahydrate is 0.3~0.5:0.1:

1.

5. A method for detecting copper ore using X-ray fluorescence spectroscopy, characterized in that, The elemental intensity of copper in the sample prepared by the preparation method according to any one of claims 1-4 is obtained by full-spectrum X-ray fluorescence spectroscopy, and the copper content in the sample is calculated by substituting it into the standard curve of the standard substance.

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