Method for extracting antimony from antimony sulfide

Abstract

The invention relates to the field of inorganic materials, in particular to a method for extracting antimony from antimony sulfide, which comprises the following steps: adding antimony sulfide into a sodium sulfide-sodium hydroxide solution, stirring for reaction to obtain a reaction solution, adding hyperbranched chitosan into the reaction solution to obtain an electrolyte, electrifying the electrolyte for electrolysis, collecting cathode precipitates, washing and drying to obtain the antimony from antimony sulfide. The antimony powder prepared by the preparation method disclosed by the invention has a bamboo-like structure, and shows excellent electrochemical performance in a lithium battery when being compounded with antimony trioxide to serve as an active material.

Description

Technical Field

[0001] This invention relates to the field of inorganic materials, specifically to a method for extracting antimony from antimony sulfide. Background Technology

[0002] Lithium-ion batteries are widely used in the electronics industry and electronic products due to their excellent characteristics such as long lifespan, large capacity, high safety performance, and environmental friendliness. Lithium-ion batteries possess advantages such as high specific capacity, high energy density, high battery voltage, environmental friendliness, long cycle life, and no memory effect, making them the most widely used and most likely to be widely applied in electric vehicles. The quality of the negative electrode material is a key factor in evaluating the quality of lithium-ion batteries. The superior performance of the negative electrode material not only affects the battery's performance but also has significant implications for reducing battery production costs and achieving large-scale production of electric vehicles.

[0003] Antimony metal has attracted widespread attention due to its high theoretical specific capacity, and is therefore considered one of the most promising anode materials for lithium-ion batteries. Currently, there are reports of Sb2O3 / Sb composite materials being used as anode materials for lithium-ion batteries. Optimizing the preparation method of antimony metal and improving its electrochemical performance has become a current research hotspot. Summary of the Invention

[0004] Objective of the invention: To address the above-mentioned technical problems, this invention proposes a method for extracting antimony from antimony sulfide.

[0005] The technical solution adopted is as follows: A method for extracting antimony from antimony sulfide: Antimony sulfide is added to a sodium sulfide-sodium hydroxide solution, and the mixture is stirred to obtain a reaction solution. Hyperbranched chitosan is added to the reaction solution to obtain an electrolyte. The electrolyte is electrolyzed, and the cathode deposits are collected, washed, dried, and calcined under argon protection to obtain antimony powder.

[0006] Furthermore, the hyperbranched chitosan is obtained by reacting carboxylated chitosan with hyperbranched polyamide amine.

[0007] Furthermore, the hyperbranched polyamide amine is obtained by reacting a diamine with an acrylate.

[0008] The diamine is any one of ethylenediamine, propylenediamine, butanediamine, pentanediamine, hexanediamine, heptamethamine, octanediamine, nonanediamine, and decanediamine.

[0009] The acrylate is any one of methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, pentyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, nonyl acrylate, and decyl acrylate.

[0010] Furthermore, the structural formula of the hyperbranched polyamide amine is shown below: .

[0011] Furthermore, the preparation method of the hyperbranched chitosan is as follows: Sodium hydroxide solution was added to acrylic acid solution, followed by chitosan. After stirring and reacting, the pH of the reaction solution was adjusted to above 10, and ethanol was added to allow the product to precipitate fully. The product was then filtered, washed, and dried to obtain carboxylated chitosan. The carboxylated chitosan was dispersed in methanol, and hyperbranched polyamide amine was added. After stirring and reacting, the product was filtered, and the solid was collected and dried.

[0012] Furthermore, the mass ratio of chitosan to acrylic acid is 1:3-5.

[0013] Furthermore, the mass ratio of the carboxylated chitosan to the hyperbranched polyamide amine is 1:3-5.

[0014] Furthermore, the amount of hyperbranched chitosan used is 10-30% of the mass of antimony sulfide.

[0015] Furthermore, the electrolysis temperature is 40-50℃, and the electrolysis current density is 100-200 A / m. 2 .

[0016] Furthermore, the roasting temperature is 500-600℃.

[0017] Furthermore, the extracted antimony powder has a bamboo-like structure.

[0018] The present invention also provides a lithium battery anode material, comprising antimony powder prepared by the above method and antimony trioxide.

[0019] The beneficial effects of this invention are: This invention provides a method for extracting antimony from antimony sulfide, wherein Sb₂S₃ can undergo the following chemical reaction in an alkaline system: Sb₂S₃ + ​​3Na₂S = 2Na₃SbS₃. Through this reaction, antimony sulfide dissolves to form Na₃SbS₃, which enters the solution, creating favorable conditions for subsequent antimony extraction.

[0020] During electrolysis, hyperbranched chitosan can react with Sb through amino and hydroxyl groups. 3+ Coordination allows hyperbranched chitosan molecules and Sb to interact. 3+The gelation between the particles and the hyperbranched structure forms a continuous film layer through physical entanglement, which encapsulates the precipitated antimony particles. At the cathode, a single antimony-hyperbranched chitosan electrodeposition film is generated. Due to the special hyperbranched structure of hyperbranched chitosan, the reduced single antimony can be fixed in the internal cavity of the hyperbranched structure, which restricts and controls the particle size and morphology of the single antimony. The generated single antimony also has good stability due to the protection.

[0021] During calcination, the complex and nonlinear molecular conformation unique to hyperbranched chitosan makes it easier for the pyrolysis products (carbonaceous residues) to form segmented, beaded, or bamboo-like micromorphological structures. Antimony particles confined within the cavities of hyperbranched chitosan undergo restricted sintering. Even if the calcination temperature does not reach the melting point of antimony, the surface diffusion ability of antimony particles is greatly enhanced at temperatures of 500-600℃. They tend to diffuse along these predefined, segmented channels, eventually connecting to form antimony powder with a bamboo-like structure.

[0022] The antimony powder prepared by this invention has a bamboo-like structure, and when combined with antimony trioxide as a negative electrode active material, it exhibits excellent electrochemical performance in lithium batteries. The core principle lies in the synergistic effect of the unique geometric characteristics of the bamboo-like structure and the buffering effect of antimony trioxide, which together solves the problem of huge volume changes and pulverization of negative electrode materials during alloying / dealloying. It also shortens the solid-state diffusion distance of lithium ions inside the active material and improves the reaction kinetics. Attached Figure Description

[0023] Figure 1 This is a SEM image of the antimony powder prepared in Example 1 of the present invention. Detailed Implementation

[0024] Unless otherwise specified in the examples, the conditions were performed under standard conditions or as recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all commercially available products. Techniques not mentioned in this invention refer to existing technologies. Unless otherwise specified, the following examples and comparative examples are parallel experiments, using the same processing steps and parameters.

[0025] Example 1: A method for extracting antimony from antimony sulfide: 23.41 g of sodium sulfide and 45 g of sodium hydroxide were added to 1 L of deionized water and stirred until dissolved to obtain a sodium sulfide-sodium hydroxide solution. 33.97 g of antimony sulfide was added to the sodium sulfide-sodium hydroxide solution, and the mixture was stirred at room temperature for 2 hours to obtain a reaction solution. Hyperbranched chitosan was added to the reaction solution and mixed thoroughly to obtain an electrolyte. The amount of hyperbranched chitosan was 20% of the mass of antimony sulfide. Low-carbon steel sheet was used as the cathode, and graphite sheet as the anode. Electrolysis was performed at a temperature of 45 ± 2 °C and a current density of 150 A / m. 2 After electrolysis, the cathode was ultrasonically cleaned in anhydrous ethanol, and the cathode deposits were collected. After washing with deionized water and anhydrous ethanol and drying, the deposits were calcined at 550℃ for 2 hours under argon protection at a rate of 5℃ / min to obtain antimony powder with a purity of 99.31% and a bamboo-like structure. Its SEM image is shown below. Figure 1 .

[0026] The preparation method of hyperbranched chitosan is as follows: 9g of ethylenediamine and 32g of methanol were added to a flask, stirred at room temperature, and 77.4g of methyl acrylate was added dropwise at a rate of approximately 1 drop per second. After the addition was complete, the mixture was reacted at room temperature for 24 hours. After the reaction was completed, methanol and excess methyl acrylate were removed by vacuum distillation to obtain an intermediate. 32.32g of the intermediate and 64g of methanol were added to a flask, and 60g of ethylenediamine was added dropwise while stirring at room temperature. After the addition was complete, the mixture was reacted for 24 hours. After the reaction was completed, methanol and excess ethylenediamine were removed by vacuum distillation to obtain hyperbranched polyamide amine. 72g of acrylic acid was dissolved in 500ml of deionized water to obtain an acrylic acid solution, and 40g of sodium hydroxide was dissolved in 500ml of deionized water to obtain a sodium hydroxide solution. The sodium hydroxide solution was added to the acrylic acid solution with stirring, followed by 18g of chitosan. The reaction was carried out at 90℃ for 5 hours with stirring. The pH of the reaction solution was adjusted to 10, centrifuged, and the supernatant was collected. 5000ml of ethanol was added dropwise to the supernatant, and the mixture was stirred at 5℃ for 1 hour. The mixture was then allowed to stand for 12 hours to allow the product to fully precipitate. The product was filtered, collected, washed with ethanol, and dried to obtain carboxylated chitosan. 10g of carboxylated chitosan was dispersed in 200ml of methanol, and 40g of hyperbranched polyamide amine was added. The mixture was stirred at room temperature for 72 hours, filtered, and the solid was collected, washed with methanol, and dried.

[0027] Example 2: A method for extracting antimony from antimony sulfide: 23.41 g of sodium sulfide and 45 g of sodium hydroxide were added to 1 L of deionized water and stirred until dissolved to obtain a sodium sulfide-sodium hydroxide solution. 33.97 g of antimony sulfide was added to the sodium sulfide-sodium hydroxide solution, and the mixture was stirred at room temperature for 2 hours to obtain a reaction solution. Hyperbranched chitosan was added to the reaction solution and mixed thoroughly to obtain an electrolyte. The amount of hyperbranched chitosan was 30% of the mass of antimony sulfide. Low-carbon steel sheet was used as the cathode, and graphite sheet as the anode. Electrolysis was performed at a temperature of 45 ± 2 °C and a current density of 200 A / m³. 2 After electrolysis, the cathode is ultrasonically cleaned in anhydrous ethanol, the cathode deposits are collected, washed with deionized water and anhydrous ethanol and dried, and then calcined at 600℃ for 2 hours under argon protection at a rate of 5℃ / min to obtain antimony powder with a purity of 99.19% and a bamboo-like structure.

[0028] The preparation method of hyperbranched chitosan is as follows: 9g of ethylenediamine and 32g of methanol were added to a flask, stirred at room temperature, and 77.4g of methyl acrylate was added dropwise at a rate of approximately 1 drop per second. After the addition was complete, the mixture was reacted at room temperature for 24 hours. After the reaction was completed, methanol and excess methyl acrylate were removed by vacuum distillation to obtain an intermediate. 32.32g of the intermediate and 64g of methanol were added to a flask, and 60g of ethylenediamine was added dropwise while stirring at room temperature. After the addition was complete, the mixture was reacted for 24 hours. After the reaction was completed, methanol and excess ethylenediamine were removed by vacuum distillation to obtain hyperbranched polyamide amine. 72g of acrylic acid was dissolved in 500ml of deionized water to obtain an acrylic acid solution, and 40g of sodium hydroxide was dissolved in 500ml of deionized water to obtain a sodium hydroxide solution. The sodium hydroxide solution was added to the acrylic acid solution with stirring, followed by 18g of chitosan. The reaction was carried out at 90℃ for 5 hours, and the pH of the reaction solution was adjusted to 10. After centrifugation, the supernatant was collected, and 5000ml of ethanol was added dropwise. The mixture was stirred at 5℃ for 1 hour, and then allowed to stand for 12 hours to allow the product to fully precipitate. The product was filtered, collected, washed with ethanol, and dried to obtain carboxylated chitosan. 10g of carboxylated chitosan was dispersed in 200ml of methanol, and 50g of hyperbranched polyamide amine was added. The mixture was stirred at room temperature for 72 hours, filtered, and the solid was collected, washed with methanol, and dried.

[0029] Example 3: A method for extracting antimony from antimony sulfide: 23.41 g of sodium sulfide and 45 g of sodium hydroxide were added to 1 L of deionized water and stirred until dissolved to obtain a sodium sulfide-sodium hydroxide solution. 33.97 g of antimony sulfide was added to the sodium sulfide-sodium hydroxide solution, and the mixture was stirred at room temperature for 2 hours to obtain a reaction solution. Hyperbranched chitosan was added to the reaction solution and mixed thoroughly to obtain an electrolyte. The amount of hyperbranched chitosan was 10% of the mass of antimony sulfide. Low-carbon steel sheet was used as the cathode, and graphite sheet as the anode. Electrolysis was performed at a temperature of 45 ± 2 °C and a current density of 100 A / m³. 2 After electrolysis, the cathode is ultrasonically cleaned in anhydrous ethanol, the cathode deposits are collected, washed with deionized water and anhydrous ethanol and dried, and then calcined at 500℃ for 2 hours under argon protection to obtain antimony powder with a purity of 99.06% and a bamboo-like structure.

[0030] The preparation method of hyperbranched chitosan is as follows: 9g of ethylenediamine and 32g of methanol were added to a flask, stirred at room temperature, and 77.4g of methyl acrylate was added dropwise at a rate of approximately 1 drop per second. After the addition was complete, the mixture was reacted at room temperature for 24 hours. After the reaction was completed, methanol and excess methyl acrylate were removed by vacuum distillation to obtain an intermediate. 32.32g of the intermediate and 64g of methanol were added to a flask, and 60g of ethylenediamine was added dropwise while stirring at room temperature. After the addition was complete, the mixture was reacted for 24 hours. After the reaction was completed, methanol and excess ethylenediamine were removed by vacuum distillation to obtain hyperbranched polyamide amine. 72g of acrylic acid was dissolved in 500ml of deionized water to obtain an acrylic acid solution, and 40g of sodium hydroxide was dissolved in 500ml of deionized water to obtain a sodium hydroxide solution. The sodium hydroxide solution was added to the acrylic acid solution with stirring, followed by 18g of chitosan. The reaction was carried out at 90℃ for 5 hours with stirring. The pH of the reaction solution was adjusted to 10, centrifuged, and the supernatant was collected. 5000ml of ethanol was added dropwise to the supernatant, and the mixture was stirred at 5℃ for 1 hour. The mixture was then allowed to stand for 12 hours to allow the product to fully precipitate. The product was filtered, collected, washed with ethanol, and dried to obtain carboxylated chitosan. 10g of carboxylated chitosan was dispersed in 200ml of methanol, and 30g of hyperbranched polyamide amine was added. The mixture was stirred at room temperature for 72 hours, filtered, and the solid was collected, washed with methanol, and dried.

[0031] Comparative Example 1: It is basically the same as Example 1, except that hyperbranched chitosan is not added.

[0032] A method for extracting antimony from antimony sulfide: 23.41 g of sodium sulfide and 45 g of sodium hydroxide were added to 1 L of deionized water and stirred until dissolved to obtain a sodium sulfide-sodium hydroxide solution. 33.97 g of antimony sulfide was added to the sodium sulfide-sodium hydroxide solution, and the mixture was stirred at room temperature for 2 hours to obtain a reaction solution. A low-carbon steel sheet was used as the cathode, and a graphite sheet as the anode. The reaction solution was electrolyzed at a temperature of 45 ± 2 °C and a current density of 150 A / m². 2 After electrolysis, the cathode is ultrasonically cleaned in anhydrous ethanol, the cathode deposits are collected, and after washing with deionized water and anhydrous ethanol and drying, antimony powder with a purity of 99.63% is obtained, and its microstructure is agglomerated granular.

[0033] Comparative Example 2: It is basically the same as Example 1, except that carboxylated chitosan is used instead of hyperbranched chitosan.

[0034] A method for extracting antimony from antimony sulfide: 23.41 g of sodium sulfide and 45 g of sodium hydroxide were added to 1 L of deionized water and stirred until dissolved to obtain a sodium sulfide-sodium hydroxide solution. 33.97 g of antimony sulfide was added to the sodium sulfide-sodium hydroxide solution, and the mixture was stirred at room temperature for 2 hours to obtain a reaction solution. Carboxylated chitosan was added to the reaction solution and mixed thoroughly to obtain an electrolyte. The amount of carboxylated chitosan was 20% of the mass of antimony sulfide. Low-carbon steel sheet was used as the cathode, and graphite sheet as the anode. Electrolysis was performed at a temperature of 45 ± 2 °C and a current density of 150 A / m. 2 After electrolysis, the cathode is ultrasonically cleaned in anhydrous ethanol, the cathode deposits are collected, washed with deionized water and anhydrous ethanol and dried, and then calcined at 550℃ for 2 hours under argon protection to obtain antimony powder with a purity of 98.68%, whose microstructure is agglomerated granular.

[0035] The preparation method of carboxylated chitosan is as follows: 72g of acrylic acid was dissolved in 500ml of deionized water to obtain an acrylic acid solution. 40g of sodium hydroxide was dissolved in 500ml of deionized water to obtain a sodium hydroxide solution. The sodium hydroxide solution was added to the acrylic acid solution with stirring, followed by the addition of 18g of chitosan. The reaction was stirred at 90℃ for 5 hours, and the pH of the reaction solution was adjusted to 10. The solution was centrifuged, and the supernatant was collected. 5000ml of ethanol was added dropwise to the supernatant, and the mixture was stirred at 5℃ for 1 hour. The mixture was then allowed to stand for 12 hours to allow the product to fully precipitate. The product was filtered, collected, washed with ethanol, and dried to obtain carboxylated chitosan.

[0036] Comparative Example 3: It is basically the same as Example 1, except that hyperbranched polyamidoamine is used instead of hyperbranched chitosan.

[0037] A method for extracting antimony from antimony sulfide: 23.41 g of sodium sulfide and 45 g of sodium hydroxide were added to 1 L of deionized water and stirred until dissolved to obtain a sodium sulfide-sodium hydroxide solution. 33.97 g of antimony sulfide was added to the sodium sulfide-sodium hydroxide solution, and the mixture was stirred at room temperature for 2 hours to obtain a reaction solution. Hyperbranched polyamide amine was added to the reaction solution and mixed thoroughly to obtain an electrolyte. The amount of hyperbranched polyamide amine was 20% of the mass of antimony sulfide. Low-carbon steel sheet was used as the cathode, and graphite sheet as the anode. Electrolysis was performed at a temperature of 45 ± 2 °C and a current density of 150 A / m. 2 After electrolysis, the cathode is ultrasonically cleaned in anhydrous ethanol, the cathode deposits are collected, and after washing with deionized water and anhydrous ethanol and drying, antimony powder with a purity of 99.12% is obtained, and its microstructure is relatively uniform granular.

[0038] The preparation method of hyperbranched polyamide amine is as follows: 9g of ethylenediamine and 32g of methanol were added to a flask, stirred at room temperature, and 77.4g of methyl acrylate was added dropwise at a rate of approximately 1 drop per second. After the addition was complete, the mixture was reacted at room temperature for 24 hours. After the reaction was completed, methanol and excess methyl acrylate were removed by vacuum distillation to obtain an intermediate. 32.32g of the intermediate and 64g of methanol were added to a flask, and 60g of ethylenediamine was added dropwise while stirring at room temperature. After the addition was complete, the mixture was reacted for 24 hours. After the reaction was completed, methanol and excess ethylenediamine were removed by vacuum distillation to obtain hyperbranched polyamide amine.

[0039] Performance testing The antimony powder prepared in Examples 1-3 and Comparative Examples 1-3, commercially available antimony powder (Beijing Yijin New Material Technology, 99.99%, 3-6mm) and commercially available antimony trioxide (Beijing Yijin New Material Technology, 99.99%, 10-50μm) were ground and mixed in a mortar at a mass ratio of 1:1 for 60 minutes to obtain samples.

[0040] The above sample, conductive agent (acetylene black), and binder (xanthan gum) were mixed in a ratio of 8:1:1 to prepare a slurry. An appropriate amount of deionized water was then added and the mixture was stirred until homogeneous. The slurry was then coated onto copper foil using a coating machine. Finally, the film was dried in a vacuum drying oven (80℃) for 12 hours. The coated film was then cut into electrode sheets with a diameter of 12 cm using a cutting machine. These sheets were then placed in a glove box. A lithium metal sheet was used as the counter electrode, and lithium hexafluorophosphate was used as the electrolyte to encapsulate the battery. After the encapsulated battery was placed for 12 hours, a charge-discharge cycle test was conducted at a current density of 200 mA / g. The test results are shown in Table 1 below. Table 1: As shown in Table 1 above, the antimony powder prepared in this invention, when combined with antimony trioxide as an active material, exhibits excellent electrochemical performance in lithium batteries.

[0041] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for extracting antimony from antimony sulfide, characterized in that, Antimony sulfide is added to a sodium sulfide-sodium hydroxide solution, and the mixture is stirred to obtain a reaction solution. Hyperbranched chitosan is added to the reaction solution to obtain an electrolyte. The electrolyte is electrolyzed, and the cathode deposits are collected, washed, dried, and calcined under argon protection to obtain antimony powder.

2. The method for extracting antimony from antimony sulfide as described in claim 1, characterized in that, The hyperbranched chitosan is obtained by reacting carboxylated chitosan with hyperbranched polyamide amine.

3. The method for extracting antimony from antimony sulfide as described in claim 2, characterized in that, The hyperbranched polyamide amine is obtained by reacting a diamine with an acrylate.

4. The method for extracting antimony from antimony sulfide as described in claim 3, characterized in that, The structural formula of the hyperbranched polyamide amine is shown below: 。 5. The method for extracting antimony from antimony sulfide as described in claim 2, characterized in that, The preparation method of the hyperbranched chitosan is as follows: Sodium hydroxide solution was added to acrylic acid solution, followed by chitosan. After stirring and reacting, the pH of the reaction solution was adjusted to above 10, and ethanol was added to allow the product to precipitate fully. The product was then filtered, washed, and dried to obtain carboxylated chitosan. The carboxylated chitosan was dispersed in methanol, and hyperbranched polyamide amine was added. After stirring and reacting, the product was filtered, and the solid was collected and dried.

6. The method for extracting antimony from antimony sulfide as described in claim 5, characterized in that, The mass ratio of chitosan to acrylic acid is 1:3-5.

7. The method for extracting antimony from antimony sulfide as described in claim 5, characterized in that, The mass ratio of carboxylated chitosan to hyperbranched polyamide is 1:3-5.

8. The method for extracting antimony from antimony sulfide as described in claim 1, characterized in that, The amount of hyperbranched chitosan used is 10-30% of the mass of antimony sulfide.

9. The method for extracting antimony from antimony sulfide as described in claim 1, characterized in that, The electrolysis temperature is 40-50℃, and the electrolysis current density is 100-200 A / m. 2 .

10. The method for extracting antimony from antimony sulfide as described in claim 1, characterized in that, The roasting temperature is 500-600℃.

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