Methods for extracting organic matter from uranium ore

Abstract

The embodiments of this application relate to the field of chemical processing of organic polymer compounds, and particularly to a method for extracting organic matter from uranium ore. The method for extracting organic matter from uranium ore provided by the embodiments of this application achieves the separation and extraction of soluble organic matter, humic acid, fulvic acid, and insoluble organic matter by processing the uranium ore sample in steps, enabling comprehensive acquisition of organic matter components in different occurrence forms in the uranium ore. By dividing the sample into two parts and extracting the soluble organic matter from the first sample and various insoluble organic matter from the second sample separately, the influence of residual reagents on the structure of humic acid and the extraction of other organic matter can be avoided, preventing organic matter loss or cross-contamination caused by traditional single extraction methods. The use of acidic liquid treatment and solid-liquid separation steps effectively removes inorganic mineral interference, improving the purity and recovery rate of each organic matter component.

Description

Technical Field

[0001] The embodiments of this application relate to the field of chemical processing of organic polymers, and particularly to a method for extracting organic matter from uranium ore. Background Technology

[0002] The statements herein are provided merely as background information in connection with this application and do not necessarily constitute prior art.

[0003] During the formation of sandstone-type uranium deposits, uranium-bearing oxidizing groundwater flows along the permeable layer. The reducing properties of the organic matter distributed in the strata reduce uranium, which originally migrated stably in the form of hexavalent uranium ions, to tetravalent uranium ions, thereby causing uranium to precipitate out of the groundwater and form uranium minerals.

[0004] Differences in the original material composition, chemical structure, and maturity of organic matter significantly affect its ability to reduce uranium, its stability, and its reaction efficiency with uranium-bearing fluids, thereby controlling the degree of uranium enrichment. Therefore, the types of organic matter in sandstone uranium deposits formed in different mineralization processes vary considerably. Identifying the main types of naturally occurring complex organic matter in uranium ore can reveal the mechanisms by which different types of organic matter play their role in the uranium mineralization process. Summary of the Invention

[0005] A brief overview of this application is provided below to offer a basic understanding of certain aspects thereof. It should be understood that this overview is not an exhaustive summary of the application. It is not intended to identify key or essential parts of the application, nor is it intended to limit its scope. Its purpose is merely to present certain concepts in a simplified form as a prelude to the more detailed description that follows.

[0006] An embodiment of this application provides a method for extracting organic matter from uranium ore, comprising the following steps: S10: collecting uranium ore; S20: preparing a first sample and a second sample based on the uranium ore; S30: extracting soluble organic matter from the first sample; S40: processing the second sample to obtain a first acidic liquid and a first solid mixture; S50: processing the first solid mixture to obtain a crude humic acid product, a second acidic liquid, and a second solid mixture; S60: processing the first acidic liquid and the second acidic liquid to obtain fulvic acid in the second sample; S70: obtaining humic acid in the second sample based on the crude humic acid product; S80: processing the second solid mixture obtained in step S50 to obtain insoluble organic matter in the second sample.

[0007] The method for extracting organic matter from uranium ore provided in the embodiments of this application achieves the separation and extraction of soluble organic matter, humic acid, fulvic acid, and insoluble organic matter by processing the uranium ore sample in steps. This method can comprehensively obtain organic matter components in different occurrence forms in uranium ore. By dividing the sample into two parts and extracting soluble organic matter from the first sample and various insoluble organic matter from the second sample separately, the method avoids the influence of residual reagents on the structure of humic acid and the extraction of other organic matter, and avoids organic matter loss or cross-contamination caused by traditional single extraction methods. The use of acidic liquid treatment and solid-liquid separation steps effectively removes inorganic mineral interference and improves the purity and recovery rate of each organic matter component. Attached Figure Description

[0008] To further illustrate the above and other advantages and features of this application, the specific embodiments of this application will be described in more detail below with reference to the accompanying drawings. The drawings, together with the following detailed description, are included in and form a part of this specification. Elements having the same function and structure are indicated by the same reference numerals. It should be understood that these drawings only depict typical examples of this application and should not be considered as limiting the scope of this application.

[0009] Figure 1 This is a schematic diagram of infrared spectral data of humic acid extracted using the method provided in the embodiments of this application; Figure 2 This is a schematic diagram illustrating the processing of the crude humic acid product obtained by extraction using the method provided in the embodiments of this application. Detailed Implementation

[0010] Exemplary embodiments of this application will be described below with reference to the accompanying drawings. For clarity and brevity, not all features of actual implementations are described in the specification. However, it should be understood that many implementation-specific decisions must be made in the development of any such actual embodiment to achieve the developer's specific goals, such as complying with constraints related to the system and business, and these constraints may vary depending on the implementation. Furthermore, it should be understood that while development work can be very complex and time-consuming, such development work is merely a routine task for those skilled in the art who benefit from the content of this application.

[0011] It should also be noted that, in order to avoid obscuring this application with unnecessary details, only the equipment structure and / or processing steps closely related to the solution according to this application are shown in the accompanying drawings, while other details that are not closely related to this application are omitted.

[0012] The following disclosure provides several different implementations or examples for carrying out this application. To simplify the disclosure of this application, specific examples of components and methods are described below. Of course, these are merely examples and are not intended to limit this application. In the description of the embodiments of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0013] Traditional methods for extracting organic matter typically involve dissolving the organic matter in a sample using acid or organic solvents, followed by analysis using instruments such as mass spectrometry or chromatography-mass spectrometry. These methods only analyze the soluble portion of the organic matter. However, the composition of natural organic matter in sandstone-type uranium deposits is extremely complex, with soluble organic matter comprising only a small fraction. Traditional methods can lead to the loss of a portion of the sample.

[0014] To address the aforementioned problems, embodiments of this application provide a method for extracting organic matter from uranium ore, comprising the following steps: S10: collecting uranium ore; S20: preparing a first sample and a second sample based on the uranium ore; S30: extracting soluble organic matter from the first sample; S40: processing the second sample to obtain a first acidic liquid and a first solid mixture; S50: processing the first solid mixture to obtain a crude humic acid product, a second acidic liquid, and a second solid mixture; S60: processing the first acidic liquid and the second acidic liquid to obtain fulvic acid in the second sample; S70: obtaining humic acid in the second sample based on the crude humic acid product; S80: processing the second solid mixture obtained in step S50 to obtain insoluble organic matter in the second sample.

[0015] The method for extracting organic matter from uranium ore provided in the embodiments of this application achieves the separation and extraction of soluble organic matter, humic acid, fulvic acid, and insoluble organic matter by processing the uranium ore sample in steps. This method can comprehensively obtain organic matter components in different occurrence forms in uranium ore. By dividing the sample into two parts and extracting soluble organic matter from the first sample and various insoluble organic matter from the second sample separately, the method avoids the influence of residual reagents on the structure of humic acid and the extraction of other organic matter, and avoids organic matter loss or cross-contamination caused by traditional single extraction methods. The use of acidic liquid treatment and solid-liquid separation steps effectively removes inorganic mineral interference and improves the purity and recovery rate of each organic matter component.

[0016] Figure 1 This is a schematic diagram of the infrared spectral data of humic acid extracted using the method provided in the embodiments of this application, as shown below. Figure 1As shown, the infrared spectrum reflects that the humic acid extracted in this application is rich in oxygen-containing functional groups, has both aromatic and aliphatic side chains, and also has intermolecular / intramolecular hydrogen bonds, indicating that the humic acid obtained by the extraction method of the embodiments of this application maintains the inherent chemical structure of humic acid and has high purity.

[0017] In some embodiments, step S50 further includes the following steps: S51: adjusting the pH of the first solid mixture to neutral; S52: adding NaOH solution to the first solid mixture in step S51 to obtain an alkaline liquid and a second solid mixture; S53: processing the alkaline liquid to obtain a second acidic liquid and a lower layer mixture; S54: centrifuging the lower layer mixture to obtain crude humic acid product.

[0018] By first adjusting the pH of the first solid mixture to neutral, the interference of residual acidic substances on subsequent processing can be eliminated, avoiding irreversible condensation or precipitation loss of humic acid due to excessive acidity. Then, NaOH solution is added to adjust the mixture to alkaline, utilizing the solubility of humic acid under alkaline conditions to transfer it from the solid mixture to the liquid phase, achieving preliminary separation of humic acid from other insoluble organic matter or minerals. Subsequently, by acidifying the alkaline liquid containing humate, a second acidic liquid is obtained, and humic acid is redeprecipitated into the lower layer mixture. This mixture is then collected by centrifugation, reducing the entrainment of inorganic impurities and insoluble residues, and yielding a high-purity crude humic acid product.

[0019] In some embodiments, in step S51, the pH can be adjusted to neutral using NaOH to avoid the introduction of other types of alkali metal ions besides sodium ions.

[0020] Preferably, in steps S51-S52, the concentration of NaOH can be 0.1-1.0 mol / L, so as to maintain the chemical integrity of humic acid and the purity of the product while ensuring extraction efficiency.

[0021] In some embodiments, step S52 further includes the following steps: S521: stirring the mixture of the first solid mixture and the NaOH solution; S522: adding Na2SO4·2H2O to the mixture obtained in step S521 and stirring and letting it stand; S523: collecting the supernatant obtained after step S522 as an alkaline liquid and collecting the remaining solid after step S522 as a second solid mixture.

[0022] By stirring to ensure full contact between the first solid mixture and the NaOH solution, humic acid can be rapidly transferred from the solid mixture to the liquid phase. Adding Na2SO4·2H2O and stirring again while allowing it to stand promotes the aggregation and sedimentation of suspended microparticles, thereby improving the solid-liquid separation effect. This facilitates the separation of the remaining solid as the second solid mixture, reducing insoluble impurities carried in the alkaline liquid, improving the purity of the humic acid product, and achieving effective separation from insoluble organic matter and mineral residues.

[0023] In some embodiments, in steps S521-S522, the mixture can be stirred evenly under a water bath at 50-70°C, and Na2SO4·2H2O can be added after 2 hours. After stirring and standing for 5 hours, the liquid can be separated into layers.

[0024] In some embodiments, step S53 further includes the following steps: S531: centrifuging and filtering the alkaline liquid; S532: adjusting the pH value of the alkaline liquid after step S531 to a predetermined range using an acidic reagent; S533: heating the liquid obtained in step S532 in a water bath to cause the liquid to separate into layers; S534: collecting the upper layer liquid obtained after step S533 as the second acidic liquid, and collecting the lower layer mixture obtained after step S533.

[0025] By using acidic reagents to adjust the pH of alkaline liquid to a predetermined range, dissolved humate salts can be converted into insoluble humic acid, which then precipitates out. Heating promotes rapid separation of the precipitate and liquid phase, and the upper liquid and lower mixture are collected separately, achieving efficient separation of fulvic acid and humic acid. This avoids interference from impurities, improves the purity of crude humic acid product, and enhances the integrity of fulvic acid recovery.

[0026] In some embodiments, in step S532, the pH value can be adjusted to a predetermined range of 1.5-2 to reduce the water solubility of humic acid molecules and promote the complete precipitation of humic acid.

[0027] In some embodiments, in step S533, the water bath heating can be followed by standing for 24 hours to separate the layers.

[0028] In some embodiments, in step S534, the second acidic liquid mainly contains the remaining fulvic acid in addition to the first acidic liquid.

[0029] In some embodiments, step S60 further includes the following steps: S61: combining the first acidic liquid and the second acidic liquid, and filtering to remove the precipitate; S62: using an adsorption resin to adsorb fulvic acid from the filtrate obtained in step S61; S63: rinsing the adsorption resin in step S62 with NaOH solution to obtain sodium fulvicate; S64: obtaining a fulvic acid solution based on the sodium fulvicate; S65: obtaining fulvic acid from the second sample based on the fulvic acid solution.

[0030] By merging the first and second acidic liquids and filtering them, solid particles can be prevented from clogging the resin or interfering with adsorption during subsequent adsorption processes. Providing NaOH solution to elute the resin containing fulvic acid allows the fulvic acid to desorb from the resin and be converted into soluble sodium fulvicate, thereby concentrating the fulvic acid in the eluent and obtaining high-purity fulvic acid. This improves the extraction and recovery rate of fulvic acid while removing inorganic salts and small molecule interfering substances, ensuring the quality of the obtained fulvic acid.

[0031] In some embodiments, in step S64, sodium fulvic acid is passed through a cation exchange resin to obtain a fulvic acid solution. This setup converts fulvic acid ions into free fulvic acid, thereby obtaining a fulvic acid solution. It simultaneously removes sodium ions and other metal cation impurities, achieving efficient and high-purity conversion of fulvic acid under mild conditions, ensuring the chemical integrity and stability of the resulting fulvic acid solution.

[0032] In some embodiments, in step S65, fulvic acid can be obtained by vacuum distillation in a water bath at 40-50°C.

[0033] In some embodiments, step S70 further includes the following steps: S71: mixing crude humic acid, KOH solution, and KCl, and centrifuging the mixture; S72: treating the mixture from step S71 with an acidic reagent to precipitate a precipitate; S73: removing silicon from the precipitate; S74: extracting humic acid from the precipitate after silicon removal. The alkaline environment provided by KOH allows the humic acid to dissolve fully, while the potassium ions in KCl enhance the ionic strength, promoting the coagulation and sedimentation of colloidal impurities, thus facilitating the removal of insoluble impurities by centrifugation.

[0034] Figure 2 This is a schematic diagram illustrating the processing of the crude humic acid product obtained by extraction using the method provided in the embodiments of this application, as shown below. Figure 2 As shown, by adding an acidic reagent to cause humic acid to redefine and precipitate, the separation of humic acid from soluble impurities is achieved; thereby removing silicon from the precipitate, the interference of silicate minerals on the purity of humic acid can be avoided, the purity of humic acid can be effectively improved and the residue of inorganic impurities such as silicon can be reduced.

[0035] In some embodiments, in step S71, before mixing the crude humic acid product, KOH solution, and KCl, the second acidic liquid with a pH value in a predetermined range (e.g., 1.5-2) obtained in step S534 can be centrifuged to separate a small amount of unprecipitated humic acid and incorporate it into the crude humic acid product.

[0036] In some embodiments, in step S71, the concentration of the KOH solution can be 0.1 mol / L, the mass of KCl can be 1.5 g, and the mixture can be centrifuged after shaking for 1 hour after mixing and dissolving.

[0037] In some embodiments, in step S72, the pH value can be adjusted to 1.5-2 using hydrochloric acid to purify humic acid and remove mineral impurities; and the precipitate can be allowed to stand for 24 hours after precipitation.

[0038] In some embodiments, in step S72, the hydrochloric acid concentration can be set to 5-6 mol / L to ensure that acid is added in the smallest volume during the process of adjusting the pH to 1.5-2, avoiding excessive dilution of the system that could lead to incomplete precipitation or difficulty in stratification of humic acid, and preventing local over-acidity that could cause degradation of humic acid, thus ensuring the integrity of the humic acid structure.

[0039] In some embodiments, step S74 further includes the following steps: S741: centrifuging the precipitate obtained in step S73; S742: washing the precipitate obtained in step S741 with distilled water; S743: dissolving the precipitate obtained in step S742 with NaOH solution; S744: adjusting the pH of the solution obtained in step S743 to a predetermined value using an acidic reagent; S745: dialyzing the solution obtained in step S744 with deionized water to obtain humic acid colloid; S746: obtaining humic acid in a second sample based on the humic acid colloid.

[0040] Centrifugation and washing of the precipitate after desiliconization remove and wash away residual dispersed impurities and soluble salts. Then, the pH value of the dissolved precipitate is adjusted to a predetermined value using an acidic reagent, which promotes the stable existence of humic acid in colloidal form rather than precipitation. Finally, dialysis with deionized water is performed to retain humic acid macromolecules, obtaining pure humic acid colloids with uniform particle size, thus obtaining a humic acid product with high chemical homogeneity.

[0041] In some embodiments, in step S744, the predetermined pH value can be around 8, which allows humic acid to exist in a stable colloidal form under weakly alkaline conditions without precipitation. At this pH value, the humic acid macromolecules remain fully dissolved and have uniform particle size, which facilitates the removal of small molecule salts, acids, bases and low molecular weight impurities during subsequent dialysis, while retaining the humic acid components, thereby obtaining a high-purity humic acid colloid with high chemical integrity.

[0042] In some embodiments, in step S746, pure humic acid can be obtained by vacuum distillation in a water bath at 40-50°C.

[0043] In some embodiments, in step S80, inorganic minerals in the second solid mixture are removed to obtain insoluble organic matter in the second sample, thereby improving the purity of the insoluble organic matter and facilitating subsequent analysis of its chemical properties and structural characteristics, while reducing the interference of inorganic minerals on the determination of organic matter.

[0044] In some embodiments, in step S80, dilute hydrochloric acid and dilute hydrofluoric acid solutions may be added to the second solid mixture to remove inorganic minerals and collect the remaining insoluble organic matter.

[0045] In some embodiments, step S40 further includes the following steps: S41: dissolving the second sample using an acidic reagent; S42: separating the dissolved second sample into layers; S43: collecting the supernatant after step S42 as the first acidic liquid, and collecting the lower layer mixture after step S42 as the first solid mixture. Through acid treatment, some soluble organic matter in the second sample is transferred to the acidic liquid, while insoluble matter remains in the lower solid mixture. This facilitates the subsequent extraction of fulvic acid, humic acid, and insoluble organic matter, and avoids cross-contamination between organic matter in different forms.

[0046] In some embodiments, in steps S41-S42, the mass ratio of the acidic reagent to the second sample can be 10:1, and the acidic reagent can be dilute hydrochloric acid. After soaking for about 5 hours, the sample is allowed to stand and separate into layers.

[0047] In some embodiments, in step S43, the first acidic liquid mainly contains fulvic acid.

[0048] In some embodiments, step S30 further includes the following steps: S31: dissolving the first sample using deionized water; S32: extracting water-soluble small-molecule organic compounds from the supernatant obtained in step S31; S33: dissolving the lower solid material obtained in step S31 using an organic solvent; S34: extracting soluble organic matter from the lower solid material obtained in step S32. By sequentially treating with water and organic solvents, the fractional extraction of soluble organic matter of different polarities from uranium ore is achieved, avoiding component mixing caused by cross-dissolution and improving the extraction efficiency and purity of various soluble organic matter.

[0049] In some embodiments, in step S31, the level of deionized water should be at least 5 cm higher than the first sample to avoid saturation and fully dissolve the water-soluble organic matter in the first sample; the dissolved first sample is subjected to ultrasonic vibration for 3-5 minutes and left to stand for 24 hours.

[0050] In some embodiments, in step S33, the lower solid material obtained in step S31 is air-dried and the sample is soaked in an organic solvent (e.g., chloroform, carbon tetrachloride, n-hexane, or ethanol) for 6 hours. The volume of the organic solvent needs to be more than twice that of the sample to fully dissolve the soluble organic matter in the first sample.

[0051] In some embodiments, in step S34, the lower solid material dissolved by water bath heating can be refluxed for 36 hours, and the extract can be subjected to low-temperature rotary evaporation to collect the residual liquid to obtain soluble organic matter.

[0052] In some embodiments, in step S34, the water bath heating temperature can be set to 70°C, 90°C, or 120°C to accommodate the dissolution rate of different types of soluble organic matter, so that different types of soluble organic matter can be fully extracted.

[0053] In some embodiments, after collecting uranium ore in step S10, the occurrence morphology, spatial location, and macroscopic organic matter characteristics (such as carbon fragments, pitch veins, etc.) of the uranium ore can be recorded.

[0054] In some embodiments, in step S20, the uranium ore collected in step S10 can be crushed, with a particle size of 100-200 mesh and a sample amount of ≥100g, and then evenly divided into two portions to obtain a first sample and a second sample.

[0055] Preferably, in step S20, the particle diameter of the first and second samples is in the range of 0.074-0.147 mm, in order to balance reaction efficiency and separation feasibility.

[0056] Regarding the embodiments of this application, it should also be noted that, without conflict, the embodiments of this application and the features in the embodiments can be combined with each other to obtain new embodiments.

[0057] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. The scope of protection of this application shall be determined by the scope of the claims.

Claims

1. A method for extracting organic matter from uranium ore, characterized in that, It includes the following steps: S10: Collect the uranium ore; S20: Prepare a first sample and a second sample based on the uranium ore; S30: Extract soluble organic matter from the first sample; S40: Process the second sample to obtain a mixture of a first acidic liquid and a first solid; S50: Process the first solid mixture to obtain crude humic acid product, a second acidic liquid, and a second solid mixture; S60: Process the first acidic liquid and the second acidic liquid to obtain fulvic acid in the second sample; S70: Obtain the humic acid in the second sample based on the crude humic acid product; S80: Process the second solid mixture obtained in step S50 to obtain the insoluble organic matter in the second sample.

2. The method according to claim 1, characterized in that, Step S50 also includes the following steps: S51: Adjust the pH of the first solid mixture to neutral; S52: Add NaOH solution to the first solid mixture in step S51 to obtain an alkaline liquid and a second solid mixture; S53: Process the alkaline liquid to obtain the second acidic liquid and the lower layer mixture; S54: Centrifuge the lower layer mixture to obtain the crude humic acid product.

3. The method according to claim 2, characterized in that, Step S52 also includes the following steps: S521: Stir the mixture of the first solid mixture and the NaOH solution; S522: Add Na2SO4·2H2O to the mixture obtained in step S521, stir and let stand; S523: Collect the supernatant obtained after step S522 as the alkaline liquid, and collect the remaining solid after step S522 as the second solid mixture.

4. The method according to claim 2, characterized in that, Step S53 also includes the following steps: S531: Centrifuge and filter the alkaline liquid; S532: Using an acidic reagent, adjust the pH value of the alkaline liquid after the treatment in step S531 to a predetermined range. S533: Heat the liquid obtained in step S532 in a water bath to cause the liquid to separate into layers; S534: Collect the upper liquid obtained after step S533 as the second acidic liquid, and collect the lower mixture obtained after step S533.

5. The method according to claim 1, characterized in that, Step S60 also includes the following steps: S61: Combine the first acidic liquid and the second acidic liquid, and filter to remove the precipitate; S62: Use adsorption resin to adsorb fulvic acid in the filtrate obtained from the filtration in step S61. S63: Rinse the adsorption resin in step S62 with NaOH solution to obtain sodium fulvic acid. S64: Obtain a fulvic acid solution based on the sodium fulvic acid salt; S65: Obtain fulvic acid from the second sample based on the fulvic acid solution.

6. The method according to claim 5, characterized in that, In step S64, the sodium fulvic acid salt is passed through a cation exchange resin to obtain the fulvic acid solution.

7. The method according to claim 1, characterized in that, Step S70 also includes the following steps: S71: Mix the crude humic acid product, KOH solution, and KCl, and centrifuge the mixture. S72: Treat the mixture from step S71 with an acidic reagent to cause a precipitate to form in the mixture; S73: Remove silicon from the precipitate; S74: Extract humic acid from the precipitate after silicon removal.

8. The method according to claim 7, characterized in that, Step S74 also includes the following steps: S741: Centrifuge the precipitate obtained in step S73; S742: Wash the precipitate obtained in step S741 with distilled water; S743: Dissolve the precipitate obtained in step S742 using NaOH solution; S744: Adjust the pH of the solution obtained in step S743 to a predetermined value using an acidic reagent; S745: Use the solution obtained in step S744 to dialyze with deionized water twice to obtain humic acid colloid; S746: Obtain the humic acid in the second sample based on the humic acid colloid.

9. The method according to claim 1, characterized in that, In step S80, inorganic minerals are removed from the second solid mixture to obtain insoluble organic matter in the second sample.

10. The method according to claim 1, characterized in that, Step S40 also includes the following steps: S41: Dissolve the second sample using an acidic reagent; S42: To separate the dissolved second sample into layers; S43: Collect the supernatant after step S42 as the first acidic liquid, and collect the lower mixture after step S42 as the first solid mixture.

11. The method according to claim 1, characterized in that, Step S30 also includes the following steps: S31: Dissolve the first sample using deionized water; S32: Extract water-soluble small molecule organic compounds from the supernatant obtained from the dissolution in step S31; S33: Dissolve the lower solid material obtained in step S31 using an organic solvent; S34: Extract soluble organic matter from the lower solid material dissolved in step S32.

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