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CN-121974328-A - Asphalt-based hard carbon material based on ion exchange method and preparation method thereof

CN121974328ACN 121974328 ACN121974328 ACN 121974328ACN-121974328-A

Abstract

The invention relates to the technical field of asphalt-based carbon material preparation and discloses an asphalt-based hard carbon material based on an ion exchange method and a preparation method thereof, and the preparation method comprises the following steps of crushing raw asphalt, placing the crushed raw asphalt in concentrated nitric acid for heating oxidation reaction, cooling, filtering and drying to obtain oxidized asphalt; taking oxidized asphalt and acetate solution to carry out ion exchange reaction under alkaline condition, filtering and separating and drying a solid product after the reaction is finished, taking the solid product to carry out carbonization treatment in nitrogen atmosphere, quickly cooling to room temperature after the carbonization treatment, carrying out acid washing, washing with water to be neutral, filtering and separating and drying to obtain the hard carbon material.

Inventors

  • HAO PAN
  • WANG YURU
  • Bu Yifang
  • ZHAO ZHITONG
  • WANG MEIJUN

Assignees

  • 太原理工大学

Dates

Publication Date
20260505
Application Date
20260211

Claims (6)

  1. 1. The preparation method of the asphalt-based hard carbon material based on the ion exchange method is characterized by comprising the following steps of: a, asphalt pretreatment: Crushing raw material asphalt, heating the crushed raw material asphalt in concentrated nitric acid at 40-80 ℃ for oxidation reaction for 6 hours, cooling the crushed raw material asphalt to be lower than 30 ℃ after the reaction is finished, filtering and drying the crushed raw material asphalt to obtain oxidized asphalt; b, ion exchange reaction Taking the oxidized asphalt prepared in the step a and an acetate solution of 1 mol.L -1 to carry out ion exchange reaction under an alkaline condition, wherein the solid-to-liquid ratio of the oxidized asphalt to the acetate solution is 1:10, and filtering, separating and drying a solid product after the reaction is finished; c, high-temperature carbonization C, carbonizing the solid product obtained in the step b in a nitrogen atmosphere at 800-1200 ℃ for 0.5-2 hours; d, washing and drying And (3) quickly cooling to room temperature after carbonization treatment, pickling, washing with water to neutrality, filtering, separating and drying to obtain the hard carbon material.
  2. 2. The method for preparing asphalt-based hard carbon material based on ion exchange method according to claim 1, wherein in the step a, coal pitch or petroleum pitch is used as the raw material pitch.
  3. 3. The method for preparing an ion exchange method-based asphalt-based hard carbon material according to claim 1, wherein the acetate solution is a calcium acetate solution, a magnesium acetate solution or a zinc acetate solution.
  4. 4. The method for preparing the asphalt-based hard carbon material based on the ion exchange method according to claim 1, wherein in the step b, the ion exchange reaction is carried out under stirring, the reaction time is 24 hours, and the alkaline condition is realized by continuously dropwise adding 0.1 mol.L -1 of NaOH solution to maintain the pH of a reaction system to be more than or equal to 8.
  5. 5. The method for preparing an asphalt-based hard carbon material based on an ion exchange method according to claim 1, wherein in the step d, 2 mol.L -1 concentrated hydrochloric acid is adopted for soaking treatment in the pickling process, and deionized water is adopted for repeatedly washing until the filtrate is neutral in the washing process.
  6. 6. The hard carbon material prepared by the method for preparing the pitch-based hard carbon material based on the ion exchange method according to claim 1.

Description

Asphalt-based hard carbon material based on ion exchange method and preparation method thereof Technical Field The invention belongs to the field of asphalt-based carbon material preparation, in particular to the field of hard carbon material preparation, and specifically relates to an asphalt-based hard carbon material based on an ion exchange method and a preparation method thereof. Background Asphalt is rich in polycyclic aromatic hydrocarbon and derivatives thereof, is an ideal precursor for preparing hard carbon materials, has carbon content of 92% -93% and hydrogen content of 3.5% -4.5%, and is an effective way for realizing high-value utilization. However, a large amount of aromatic structures in asphalt easily generate pi-pi stacking effect, so that products with compact structures, less pore structures and too high graphitization degree are formed after the asphalt is carbonized, and the sodium storage function cannot be realized. To solve the above problems, the prior art generally adopts a chemical activation method or a template method to treat asphalt by increasing pore structure and inhibiting excessive graphitization: The chemical activation method is to etch the carbon precursor at high temperature to introduce pores to increase porosity using alkali metal salts (e.g., KOH, naOH, K 2CO3、Na2CO3) or acidic compounds (ZnCl 2、H3PO4) or the like as an active agent. The template method is to mix and carbonize template agents such as CaO, caCO 3 and the like with raw asphalt to form a cross-linked structure, so as to realize pore-forming and inhibit excessive graphitization. However, in the above method, when an activator or a template agent is used, a mechanical mixing or impregnating mode is mostly adopted, and the asphalt and the modifier (the activator and the template agent) are mainly in physical contact or surface action, so that the action mode is weak, deep molecular modification is difficult to realize, the regulation and control on the material structure are limited, and the improvement on the sodium storage capacity of the material is limited. In order to solve the problems, the invention provides an asphalt-based hard carbon material based on an ion exchange method and a preparation method thereof. Disclosure of Invention The invention provides an ion exchange method-based asphalt-based hard carbon material and a preparation method thereof, and aims to solve the problems that in the process of preparing a hard carbon material by utilizing asphalt by adopting a chemical activation method or a template method, the contact effect between asphalt and a modifier or a template agent is weak, the modification degree is weak, the regulation and control of the material are limited, excessive graphitization is easy, and the sodium storage capacity improving effect is affected. The invention is realized by adopting the following technology: The invention provides a preparation method of an asphalt-based hard carbon material based on an ion exchange method, which comprises the following steps: a, asphalt pretreatment: crushing raw material asphalt, namely coal asphalt or petroleum asphalt, placing the raw material asphalt into concentrated nitric acid, heating the raw material asphalt at 40-80 ℃ for oxidation reaction for 6 hours, cooling the raw material asphalt to be lower than 30 ℃ after the reaction is finished, and filtering and drying the raw material asphalt to obtain oxidized asphalt. B, ion exchange reaction And c, carrying out ion exchange reaction on the oxidized asphalt prepared in the step a and an acetate solution of 1 mol.L -1 under an alkaline condition, wherein the solid-to-liquid ratio of the oxidized asphalt to the acetate solution is 1:10, the acetate solution is specifically a calcium acetate solution, a magnesium acetate solution or a zinc acetate solution, the ion exchange reaction is carried out under stirring, the reaction time is 24 hours, the alkaline condition is realized by continuously dropwise adding a NaOH solution of 0.1 mol.L -1 to maintain the pH of a reaction system to be more than or equal to 8, and filtering, separating and drying a solid product after the reaction is finished. In the ion exchange process, carboxyl in the oxidized asphalt can exchange with divalent metal in acetate, so that metal ions are exchanged into the organic structure of the oxidized asphalt to form organic matter crosslinking sites. C, high-temperature carbonization And C, carbonizing the solid product obtained in the step b in a nitrogen atmosphere at 800-1200 ℃ for 0.5-2 hours. D, washing and drying And (3) quickly cooling to room temperature after carbonization treatment, pickling, and washing with water to neutrality, wherein the pickling is carried out by adopting 2 mol.L -1 concentrated hydrochloric acid for soaking treatment, the washing is carried out by adopting deionized water to repeatedly wash until filtrate is neutral, and filtering, separating and drying are carried out t