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CN-122006729-A - MOF-derived Sm doped Co3O4Method for preparing catalyst and application of catalyst in water treatment

CN122006729ACN 122006729 ACN122006729 ACN 122006729ACN-122006729-A

Abstract

The invention belongs to the technical field of Sm doped Co 3 O 4 catalyst preparation, and particularly relates to a preparation method of an MOF-derived Sm doped Co 3 O 4 catalyst and application thereof in water treatment, wherein a solution A and a solution B are prepared, and the solution A is a 2-methylimidazole aqueous solution; the solution B is a mixed aqueous solution of cobalt salt, samarium salt and cetyl trimethyl ammonium bromide, the solution B is slowly dripped into the solution A, stirring is carried out, generated precipitate is collected, the precipitate is washed and dried to obtain Sm-ZIF-67 precursor, the Sm-ZIF-67 precursor is placed in an air atmosphere for calcination, and the Sm-ZIF-67 precursor is ground after being naturally cooled to room temperature to obtain the MOF-derived Sm doped Co 3 O 4 catalyst.

Inventors

  • ZHANG HUA
  • CHEN CHAOFA
  • ZHANG KUANKUAN
  • WU QINGQING

Assignees

  • 中国科学院地球化学研究所

Dates

Publication Date
20260512
Application Date
20260409

Claims (10)

  1. 1. A preparation method of an MOF-derived Sm doped Co 3 O 4 catalyst is characterized by comprising the following steps: Preparing a solution A and a solution B, wherein the solution A is a 2-methylimidazole aqueous solution, and the solution B is a mixed aqueous solution of cobalt salt, samarium salt and cetyltrimethylammonium bromide; slowly dripping the solution B into the solution A, stirring for reaction, and collecting the generated precipitate; washing and drying the precipitate to obtain a Sm-ZIF-67 precursor; And fourthly, calcining the Sm-ZIF-67 precursor in an air atmosphere, naturally cooling to room temperature, and grinding to obtain the MOF-derived Sm doped Co 3 O 4 catalyst.
  2. 2. The method for preparing the MOF-derived Sm doped Co3O4 catalyst according to claim 1, wherein the dosage ratio of 2-methylimidazole to deionized water in the solution A is 9 g/80 mL; Solution B contains 、 And 10mg of cetyl trimethylammonium bromide, with 20mL deionized water as solvent.
  3. 3. The method of claim 1, wherein the stirring reaction conditions in the second step are 25 ℃ for 3 hours.
  4. 4. The method for preparing the MOF-derived Sm doped Co 3 O 4 catalyst according to claim 1, wherein the precipitate is collected by centrifugation in the second step, and the centrifugation parameter is 8000rpm for 10min.
  5. 5. The method for preparing the MOF-derived Sm doped Co 3 O 4 catalyst according to claim 1, wherein in the third step, ethanol and deionized water are used for washing alternately, and the washing is repeated for 3 times; The drying conditions were 60 ℃ drying overnight.
  6. 6. The method of claim 1, wherein the temperature rise rate of the calcination in the fourth step is 2 ℃ per minute, the calcination temperature is 400 ℃, and the thermal insulation calcination time is 4 hours.
  7. 7. The method of claim 1, wherein Sm 3+ is atomically uniformly doped in the Co 3 O 4 spinel lattice to replace part of octahedral Co 3+ sites and form a Co-O-Sm bridging unit.
  8. 8. The method for preparing the MOF-derived Sm doped Co 3 O 4 catalyst according to claim 1, wherein Co 3+ is in an intermediate spin state, and the active sites of the catalyst are uniformly dispersed and have large specific surface area.
  9. 9. The method for preparing the MOF-derived Sm doped Co 3 O 4 catalyst according to claim 1, wherein the method can be scaled up to kilogram scale preparation, and the morphology, crystal form and catalytic performance of the scaled-up catalyst are consistent with those of laboratory samples.
  10. 10. The application of the MOF-derived Sm doped Co 3 O 4 catalyst in water treatment is based on the preparation method of the MOF-derived Sm doped Co 3 O 4 catalyst according to any one of claims 1-9, and is characterized in that the catalyst is prepared by the preparation method according to any one of claims 1-9 and is used for activating peroxymonosulfate to degrade refractory organic pollutants in water; The refractory organic pollutants comprise at least one of antibiotic pollutants, phenolic compounds and industrial dyes; the antibiotic pollutants are at least one of sulfamethoxazole, terramycin, tetracycline, ciprofloxacin and norfloxacin; The phenolic compound is at least one of bisphenol A, phenol and 4-chlorophenol; The industrial dye is at least one of rhodamine B, methylene blue and Congo red; The pH range of the water body suitable for water treatment is 3-11; The water body comprises at least one of tap water, river water and medical wastewater.

Description

Preparation method of MOF-derived Sm-doped Co 3O4 catalyst and application of MOF-derived Sm-doped Co 3O4 catalyst in water treatment Technical Field The invention belongs to the technical field of catalyst preparation, in particular relates to a preparation method of a rare earth doped metal oxide catalyst, and particularly relates to a MOF derived Sm doped catalystThe preparation method of the catalyst and the application of the catalyst in activating the peroxymonosulfate to degrade organic pollutants difficult to degrade in water. Background As a typical spinel type heterogeneous cobalt-based catalyst, the catalyst has the advantages of good environmental compatibility, stable structure and moderate cost, and is a common catalytic material for activating PMS. However, pure phasesThere are a number of technical drawbacks: Firstly, the intrinsic activity of the catalytic active site is low, and the electron transfer efficiency is poor; secondly, the PMS activation path is difficult to accurately regulate and control, the generation selectivity of sulfate radical is poor, and various active species are easy to generate and cause side reactions; thirdly, the catalyst active site is easy to agglomerate, the specific surface area is small, the contact area with pollutants is limited, the overall degradation efficiency is low, and the defects seriously limit the large-scale application of the catalyst in the actual water treatment engineering. Doping modification is optimizationThe electron structure and the effective technical path for improving the catalytic performance of the rare earth element have unique 4f electron configuration, rich coordination sites and strong electronegativity, and after the rare earth element is doped into a metal oxide lattice, the electron density, the lattice structure and the spin state of the metal sites can be effectively regulated, so that the catalytic activity and the stability of the catalyst are greatly improved. The metal organic framework derivatization method is a process for preparing metal oxide by taking MOF material as a precursor and calcining at high temperature, can effectively retain the porous structure and the morphological characteristics of the MOF material, can prepare the metal oxide catalyst with regular morphology, uniform dispersion of active sites, rich pore channel structure and larger specific surface area, and provides reliable technical support for the precise regulation and control of the structure of the catalyst. At present, rare earth samarium dopingThe research of the catalyst is still in a starting stage, and a plurality of short plates exist in the prior art: first, no mature, stable and scalable MOF-derived Sm doping has been formed The preparation process of the catalyst is complex, the reaction condition is harsh, and batch production is difficult to realize in the existing preparation method; second, regarding Sm doping pairs The regulation and control mechanism of the medium Co ion spin state and the influence of the regulation and control mechanism on the PMS activation path and the directional generation of sulfate radical lack of a system and intensive research; thirdly, the prepared catalyst has poor adaptability to the actual water body, is easily interfered by water body matrixes, has insufficient circulation stability and higher metal leaching amount, and cannot meet the actual requirements of industrial water treatment. Therefore, a MOF-derived Sm doping with simple process, large-scale preparation, excellent catalytic performance and strong stability is developedThe catalyst is used for solving the technical problems. Disclosure of Invention In view of the deficiencies of the prior art, the present invention aims to provide a MOF-derived Sm dopingThe catalyst prepared by the method has regular shape, uniform dispersion of active sites, accurate regulation and control of the spin state of Co ions, realization of directional generation of sulfate radicals, high-efficiency degradation capability on nondegradable organic pollutants in water, wide applicable pH range, excellent cycle stability, low metal leaching amount and suitability for various actual water treatment scenes. Another object of the present invention is to provide the MOF-derived Sm doping described aboveThe catalyst is used for activating peroxymonosulfate to degrade refractory organic pollutants in water, wherein the refractory organic pollutants comprise antibiotics such as sulfamethoxazole, phenolic compounds and industrial dyes, and the catalyst has the advantages of high degradation efficiency and high reaction speed and has good industrial application prospect. In order to achieve the aim of the invention, the invention adopts the following technical scheme: MOF-derived Sm doping A method for preparing a catalyst comprising the steps of: Preparing a solution A and a solution B, wherein the solution A is a 2-methylimidazole aqueous solution, and the solution