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CN-121972198-A - Self-template preparation method, regeneration method and application of thermal oxidation resistant boron-nitrogen co-doped carbon catalyst

CN121972198ACN 121972198 ACN121972198 ACN 121972198ACN-121972198-A

Abstract

The invention discloses a thermal oxidation resistant boron nitrogen co-doped carbon catalyst, and a self-template preparation and regeneration method and application thereof. The catalyst is prepared by taking Chinese medicinal licorice slag as a self-template carbon skeleton precursor, mixing the self-template carbon skeleton precursor with urea and boric acid according to the mass ratio of 1:1:1, and performing one-step pyrolysis under the air atmosphere. The preparation method uses the endogenous minerals of the licorice slag as a template, and under the fluxing and lattice stabilization actions of boric acid, a stable carbon skeleton with covalently anchored boron and nitrogen atoms is successfully constructed, so that the stable carbon skeleton can resist high-temperature aerobic calcination at 700 ℃. The catalyst can efficiently activate the peroxymonosulfate at pH 1 11 Can realize rapid degradation and deep mineralization of various organic pollutants such as sulfonamides, tetracyclines, phenols and the like within a wide range. The invention realizes the treatment of waste by waste, overcomes the technical bottleneck that the carbon-based catalyst is difficult to regenerate at high temperature, has the characteristics of high activity, long service life and low cost, and has wide application prospect in the field of advanced treatment of organic pollutants in water.

Inventors

  • WANG YAZHOU
  • WEN ZHANGFENG
  • HUANG DI
  • LI RUIPING
  • HUANG YINGPING

Assignees

  • 三峡大学

Dates

Publication Date
20260505
Application Date
20260120

Claims (10)

  1. 1. A preparation method of a self-template of a thermal oxidation resistant boron nitrogen co-doped carbon catalyst is characterized by using Chinese medicinal licorice root residue containing endogenous minerals as a self-template carbon skeleton precursor, and specifically comprises the following steps of: S1, boiling, washing and drying the Chinese medicinal licorice residues, and crushing the Chinese medicinal licorice residues into powder; s2, mixing and grinding urea and boric acid, then adding the mixture into the licorice residue powder obtained in the S1, enabling the mass ratio of the licorice residue to the urea to the boric acid to be 1:1, and uniformly mixing; s3, placing the mixture obtained in the step S2 in a high-temperature tube furnace, calcining at high temperature under the air atmosphere, and forming a stable porous carbon skeleton structure under the action of boric acid fluxing by taking endogenous minerals in licorice residues as self-templates; and S4, cooling, grinding, washing and drying the calcined product to obtain the thermal oxidation resistant boron-nitrogen co-doped carbon catalyst.
  2. 2. The method for preparing the self-template of the thermal oxidation resistant boron nitrogen co-doped carbon catalyst according to claim 1, wherein in the step S3, the high-temperature calcination temperature is 600-800 ℃, the temperature rising rate is 5-15 ℃ per minute, and the heat preservation time is 1-3 hours.
  3. 3. The method for preparing the self-template of the thermal oxidation resistant boron nitrogen co-doped carbon catalyst according to claim 2, wherein the high-temperature calcination condition is controlled to be 700 ℃, the temperature rising rate is 10 ℃ per minute, and the heat preservation time is 2 hours.
  4. 4. A method for regenerating a boron nitrogen co-doped carbon catalyst resistant to thermal oxidation, characterized in that the catalyst is prepared by the method according to any one of claims 1 to 3, and the regeneration method comprises thermal regeneration or solvent regeneration: The thermal regeneration is specifically as follows: Heat treating the used catalyst in oxygen-containing atmosphere at 600-800 deg.c for 1-3 hr; the solvent regeneration is specifically as follows: the used catalyst is subjected to a pickling treatment with at least one of an acidic solution, an alkaline solution or an organic alcohol solution, and then washed to neutrality and dried.
  5. 5. The method for regenerating a boron nitrogen co-doped carbon catalyst according to claim 4 wherein the thermal regeneration is carried out under the condition that the temperature is raised to 700 ℃ at a rate of 5-15 ℃ per minute in an air atmosphere and the temperature is kept at 700 ℃ for 2 hours.
  6. 6. The method for regenerating a boron nitrogen co-doped carbon catalyst according to claim 4, wherein in the solvent regeneration, the acidic solution is a hydrochloric acid solution of 0.05-0.5mol/L, the alkaline solution is a sodium hydroxide solution of 0.05-0.5mol/L, and the organic alcohol solution is an ethanol solution with a concentration of not less than 90%.
  7. 7. The method for regenerating a boron nitrogen co-doped carbon catalyst according to claim 6, wherein the acidic solution is 0.1 mol/L hydrochloric acid solution, the alkaline solution is 0.1 mol/L sodium hydroxide solution, and the organic alcohol solution is 95% ethanol solution.
  8. 8. Use of a thermal oxidation resistant boron nitrogen co-doped carbon catalyst prepared according to any one of claims 1-3 for activating peroxymonosulfate for degrading organic contaminants in water.
  9. 9. The method of claim 8, wherein the organic contaminant is at least one selected from the group consisting of sulfadimidine, terramycin, 3-aminophenol, sulfadiazine, chlortetracycline hydrochloride, sulfamethoxazole and bisphenol A.
  10. 10. The method of claim 8, wherein the catalyst is added in an amount of 0.3-0.6 g/L, the concentration of the peroxymonosulfate is 0.1-0.5 g/L, and the pH value of the reaction system is 1-11.

Description

Self-template preparation method, regeneration method and application of thermal oxidation resistant boron-nitrogen co-doped carbon catalyst Technical Field The invention relates to the technical field of environmental functional materials and water treatment engineering, in particular to a preparation method, a regeneration method and application of a self-template of a thermal oxidation resistant boron nitrogen co-doped carbon catalyst. Background With the rapid development of industries such as medicine and chemical industry, persistent Organic Pollutants (POPs) represented by sulfonamide antibiotics (such as Sulfadimidine (SMZ)) and endocrine disruptors (such as bisphenol A (BPA)) continuously enter water environment, and the POPs have serious threats to ecosystems and human health due to poor biodegradability, easy accumulation and biotoxicity. Conventional water treatment processes have difficulty achieving efficient removal and deep mineralization of such contaminants. Advanced oxidation techniques (AOPs) based on Peroxomonosulphate (PMS) are one of the effective means of degrading such refractory organic pollutants because of their ability to generate strongly oxidising free radicals. The activation of PMS generally requires a catalyst, carbon-based catalysts are of great interest because of their wide sources, environmental friendliness, and no risk of metal leaching. However, the existing carbon-based catalyst has two common bottlenecks in practical application, namely poor structural stability, easy poisoning and deactivation caused by adsorption of organic intermediates in the catalytic process, incomplete regeneration of conventional solvents, most thorough high-temperature aerobic thermal regeneration (such as calcination at 700 ℃) can lead to oxidization and ablation of a common biochar framework, repeated use can not be realized, short service life, weak engineering applicability, easy loss and difficult separation and recovery of the powder catalyst in practical water treatment, and restriction of large-scale application of the powder catalyst. Meanwhile, the Chinese traditional medicine industry produces tens of millions of tons of extraction residues such as licorice residues each year, and the extraction residues are mostly disposed in an incineration or landfill mode at present, so that not only is the resource wasted, but also the environmental pressure is brought. Therefore, the nonmetal carbon catalyst which can take the traditional Chinese medicine waste residue as the raw material and has high catalytic activity, excellent structural stability and good engineering applicability is developed, and has important significance for promoting 'treating waste with waste' and realizing high-efficiency sustainable treatment of refractory organic pollutants. Disclosure of Invention The invention aims to solve the technical problem of providing a self-template preparation method, a regeneration method and application of a thermal oxidation resistant boron nitrogen co-doped carbon catalyst, which utilize Chinese medicinal licorice root residue rich in endogenous minerals as a self-template carbon skeleton precursor, and through co-doping and one-step pyrolysis of urea and boric acid, boron and nitrogen atoms are covalently anchored in a carbon skeleton under the fluxing and lattice stabilizing actions of the boric acid, a stable structure capable of tolerating 700 ℃ high-temperature aerobic calcination is successfully constructed, so that the catalyst can be completely regenerated through simple high-temperature heat treatment, and the service life is greatly prolonged. In order to solve the technical problems, the invention adopts the following technical scheme: The invention provides a self-template preparation method of a thermal oxidation resistant boron nitrogen co-doped carbon catalyst. The method creatively utilizes the Chinese medicinal licorice slag rich in endogenous minerals as a self-template carbon skeleton precursor, and constructs the catalyst with stable structure in the one-step pyrolysis process through the synergistic effect of boric acid and urea. The method specifically comprises the following steps: S1, boiling, washing and drying the Chinese medicinal licorice residues, and crushing the Chinese medicinal licorice residues into powder; s2, mixing and grinding urea and boric acid, then adding the mixture into the licorice residue powder obtained in the step S1, enabling the mass ratio of the licorice residue powder to the urea to the boric acid to be 1:1, and uniformly mixing; s3, placing the mixture obtained in the step S2 in a high-temperature tube furnace, calcining at high temperature in an air atmosphere, and utilizing endogenous minerals in licorice slag as self-templates to promote boron atoms and nitrogen atoms to be covalently anchored in a carbon skeleton under the fluxing and lattice stabilizing actions of boric acid at high temperature, so that a heat and oxidat