Copper ore sample preparation and detection method for X-ray fluorescence spectrum analysis

Abstract

The invention relates to a preparation and detection method of a copper ore sample for X-ray fluorescence spectrum analysis. The preparation method comprises the following steps: mixing ore coarse powder and a binder, and grinding; paving a layer of boric acid in a tabletting ring, uniformly paving the powder on the boric acid, and pressing by using a tabletting machine to obtain a tabletting sample; the binder is obtained by coordination of polyacrylic acid and polyvinyl alcohol europium nitrate. According to the invention, a sample formed by pressing by uniformly paving the prepared adhesive-containing fine powder on a common adhesive boric acid for bottoming is more uniform and compact, has a firm structure and a flat and crack-free surface, and does not fall off slag; the prepared tablet is directly tested by an X-ray fluorescence spectrometry, so that the operation efficiency is high, and the analysis data is reliable; the rare earth material is applied to the X-ray fluorescence spectrum analysis of the copper ore for the first time, has a synergistic effect on fluorescence imaging, and does not interfere with a main peak; the process of dissolving, heating, cooling and curing is omitted through direct tabletting, polyacrylic acid and polyvinyl alcohol serve as ligands, the bonding effect is achieved, and it is guaranteed that tablets are compact and complete.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ore metal element analysis, in particular to a preparation and detection method of X-ray fluorescence spectrum analysis of copper ore samples. BACKGROUND

[0002] X-ray fluorescence spectrometry has the characteristics of simple sample preparation, simple analysis and fast speed. Determining the content of each component in the ore by X-ray fluorescence spectrum has important significance for the value of ore exploitation. In the early stage, the sample to be measured was prepared by melting, which can well eliminate the particle effect, but the sample preparation process is complex and time-consuming. At present, the sample is prepared by powder pressing method, which is low in cost and simple and efficient. When the powder is pressed into a sheet, the sheet structure is easy to loosen, which affects the detection results, so a binder is often used to ensure the integrity of the sheet.

[0003] For example, the invention patent CN103207197B discloses an X-ray fluorescence spectrum analysis method for copper content in copper ore, which proposes a method for preparing an analysis sample sheet using a solidifying agent. However, this method still needs acid hydrolysis pretreatment to obtain crystalline salt, and the crystalline salt is mixed with the solidifying agent, heated and then cooled and solidified into a sheet, which is still time-consuming, and the solidifying agent used is agarose and konjac gum, which is easy to be damp and has high storage conditions. SUMMARY

[0004] In view of the deficiencies in the prior art, the present application provides a method for preparing ore samples to be measured by pressing method and quantitatively analyzing elements by X-ray fluorescence spectrometer.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical scheme: A preparation method of X-ray fluorescence spectrum analysis of copper ore sample, comprising the following steps: S1, crushing and grinding the ore raw material to obtain coarse powder; S2, mixing the coarse powder with 0.04~0.08wt% of the binder and then grinding again to obtain fine powder; S3, laying a layer of boric acid in the sheet pressing ring, evenly laying the fine powder on the boric acid, and using a sheet pressing machine to press, thereby obtaining; The preparation process of the binder is as follows: Polyacrylic acid and polyvinyl alcohol are weighed in a reaction bottle, 70% ethanol solution is added and stirred to dissolve, then europium nitrate hexahydrate is added, ammonia water is added dropwise to adjust pH=7, and heated to reflux at 70~90℃ for 2h, then concentrated to obtain a solid, dried and ground to obtain the binder.

[0006] Further, the particle size of the fine powder is <200 mesh.

[0007] Furthermore, the pressure during the tableting process is 30-40t, the holding time is 30-50s, and the depressurization time is 10-15s.

[0008] 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.

[0009] 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.

[0010] 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

[0011] Figure 1 The copper content-strength standard working curve was established for this case. Detailed Implementation

[0012] 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.

[0013] 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.

[0014] Example 1: Sample Preparation S1. The ore raw material is crushed and ground to obtain coarse powder; S2. Mix the coarse powder with 0.05wt% 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 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.

[0015] The obtained sample has a smooth and clean surface without cracks.

[0016] Example 2: X-ray fluorescence spectroscopy analysis of copper content in copper ore I. Establishing a Standard Curve 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; 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.

[0017] I =30.33·C-5.87(R 2 =0.998) 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.

[0018] Table 1 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.

[0019] Table 2 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.

[0020] 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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