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CN-121990571-A - Porous carbon material based on synergistic activation of PVC and PET, and preparation method and application thereof

CN121990571ACN 121990571 ACN121990571 ACN 121990571ACN-121990571-A

Abstract

The application relates to a porous carbon material based on PVC and PET synergistic activation, a preparation method and application thereof, and relates to the technical field of coal-based solid waste recycling, wherein the porous carbon material is prepared by taking coal gasification fine slag as a carbon source, taking polyvinyl chloride and polyethylene terephthalate as synergistic activators and supplementary carbon sources and adopting an acid washing pretreatment and alkali coactivation process, and has a hierarchical pore structure, a specific surface area of 700-950, a pore volume of 0.45-0.75 and a carbon dioxide adsorption capacity of more than 45 under the atmospheric pressure of 0 ℃ and1 standard. According to the application, three solid wastes with heavy environmental burden are converted into products with higher added value by using waste to treat waste, so that the problems of solid waste piling pollution and recycling are synchronously solved.

Inventors

  • SONG XUDONG
  • ZHOU YING
  • LU YUE
  • LV PENG
  • BAI YONGHUI
  • SU WEIGUANG
  • WANG JIAOFEI
  • YU GUANGSUO

Assignees

  • 宁夏大学

Dates

Publication Date
20260508
Application Date
20260211

Claims (10)

  1. 1. The porous carbon material based on the synergistic activation of PVC and PET is characterized in that coal gasification fine slag is used as a carbon source, polyvinyl chloride and polyethylene terephthalate are used as synergistic activators and supplementary carbon sources, and the porous carbon material is prepared through pickling pretreatment and alkali coactivation processes, and has a hierarchical pore structure, and the specific surface area is 700-950 Pore volume of 0.45-0.75 Carbon dioxide adsorption capacity at 0 ℃ and 1 standard atmospheric pressure is greater than 45 。
  2. 2. The porous carbon material based on the synergistic activation of PVC and PET according to claim 1, wherein the hierarchical pore structure comprises micropores and mesopores, the pore diameter of the micropores is less than 2nm, the pore diameter of the mesopores is 2-50 nm, the Raman spectrum ID/IG value of the porous carbon material is less than 1.10, and the content of oxygen-containing functional groups on the surface measured by X-ray photoelectron spectroscopy is less than 5at%.
  3. 3. The porous carbon material based on synergistic activation of PVC and PET according to claim 1, wherein the adsorption capacity retention rate is not less than 97% after 10 cycles of carbon dioxide adsorption-desorption.
  4. 4. A method for producing the porous carbon material according to any one of claims 1 to 3, comprising the steps of: S1, mixing coal gasification fine slag with an acid solution, reacting for 4-6 hours at 50-70 ℃, filtering, washing to be neutral, and drying to obtain pickling slag; S2, mixing the acid washing slag, the alkali activator, the polyvinyl chloride powder and the polyethylene terephthalate powder according to the mass ratio of 1 (2-4) (0.05-0.2) (0.5-1.5); s3, activating the mixed material in an inert atmosphere at 800-900 ℃ for 1-3 hours; S4, neutralizing the activated product with an acid solution, washing to neutrality, and drying to obtain the porous carbon material.
  5. 5. The method according to claim 4, wherein in the step S1, the acid solution is hydrochloric acid solution and hydrofluoric acid solution, and the acid washing pretreatment comprises mixing the gasified fine slag with 20% hydrochloric acid solution according to a solid-to-liquid ratio of 1:8-12, and mixing the solid with 40% hydrofluoric acid solution according to the same solid-to-liquid ratio.
  6. 6. The method according to claim 4, wherein in the step S2, the mass ratio of the acid washing slag, the alkali activator, the polyvinyl chloride and the polyethylene terephthalate is 1:2:0.05:1 or 1:4:0.1:1.
  7. 7. The method according to claim 4, wherein in the step S2, the alkali activator is potassium hydroxide or sodium hydroxide, and the polyvinyl chloride powder and the polyethylene terephthalate powder have a particle size of 80 to 200 mesh.
  8. 8. The method according to claim 4, wherein in step S3, the activation is performed under a nitrogen atmosphere at a temperature rise rate of 3 to 10 ℃ per minute, an activation temperature of 850 ℃ and an activation time of 2 hours.
  9. 9. The method according to claim 4, wherein in step S4, the acid solution is 1-5% hydrochloric acid solution by mass, and the drying is performed at 80 ℃ for 8-12 hours.
  10. 10. Use of a porous carbon material according to any one of claims 1-3 as an adsorbent for capturing carbon dioxide in flue gas, industrial exhaust gas or atmosphere, at an adsorption temperature of 0-50 ℃ and an adsorption pressure of 0.1-2 bar.

Description

Porous carbon material based on synergistic activation of PVC and PET, and preparation method and application thereof Technical Field The application relates to the technical field of coal-based solid waste recycling, in particular to a porous carbon material based on PVC and PET synergistic activation, and a preparation method and application thereof. Background With the global promotion of 'carbon peak, carbon neutralization' targets, the development of low-energy-consumption and high-efficiency carbon dioxide capturing technologies is of great importance. The adsorption method based on the solid adsorbent becomes a research hot spot because of flexible operation and convenient regeneration, and the core is to develop the adsorption material with low cost and high performance. The Coal Gasification Fine Slag (CGFS) is a large amount of industrial solid waste generated by coal gasification, contains unburned carbon and can be used as a cheap carbon source for preparing porous carbon materials. The prior researches mainly improve the pores of the material through physical or chemical activation, but the obtained material has the common problems of low micropore proportion and limited specific surface area improvement, so that the carbon dioxide adsorption capacity (especially at normal temperature) is difficult to meet the requirement. At the same time, disposal of waste plastics such as polyvinyl chloride (PVC) and polyethylene terephthalate (PET) is also an environmental issue. Researches show that PVC pyrolysis can release hydrogen chloride, has the potential of being used as an in-situ pore-forming agent, and can be used in cooperation with alkaline agents such as KOH and the like to remarkably improve the specific surface area and carbon dioxide adsorption performance of the obtained activated carbon. PET has high carbon content and unique structure, and can be used as a supplementary carbon source. Therefore, there is a need for a porous carbon material that can cooperatively utilize three solid wastes, namely coal gasification fine slag, PVC and PET, for capturing and separating carbon dioxide. Disclosure of Invention The invention aims to solve the technical problems of raw material performance bottleneck, single solid waste disposal and difficult collaborative optimization of a pore structure in the prior art by providing a porous carbon material based on collaborative activation of PVC and PET and a preparation method and application thereof. In order to achieve the above purpose, the present invention provides the following technical solutions: The porous carbon material based on the synergistic activation of PVC and PET, as well as the preparation method and the application thereof, is prepared by taking coal gasification fine slag as a carbon source, taking polyvinyl chloride and polyethylene terephthalate as synergistic activators and supplementary carbon sources through pickling pretreatment and alkali coactivation processes, and has a hierarchical pore structure and a specific surface area of 700-950 Pore volume of 0.45-0.75Carbon dioxide adsorption capacity at 0 ℃ and 1 standard atmospheric pressure is greater than 45。 Further, the hierarchical pore structure comprises micropores and mesopores, the pore diameter of the micropores is smaller than 2 nm, the pore diameter of the mesopores is 2-50 nm, the Raman spectrum ID/IG value of the porous carbon material is smaller than 1.10, and the content of oxygen-containing functional groups on the surface measured by X-ray photoelectron spectroscopy is smaller than 5at%. Further, after 10 carbon dioxide adsorption-desorption cycles, the adsorption capacity retention rate of the porous carbon material is not lower than 97%. A method for preparing a porous carbon material as described above, comprising the steps of: S1, mixing coal gasification fine slag with an acid solution, reacting for 4-6 hours at 50-70 ℃, filtering, washing to be neutral, and drying to obtain pickling slag; S2, mixing the acid washing slag, the alkali activator, the polyvinyl chloride powder and the polyethylene terephthalate powder according to the mass ratio of 1 (2-4) (0.05-0.2) (0.5-1.5); s3, activating the mixed material in an inert atmosphere at 800-900 ℃ for 1-3 hours; S4, neutralizing the activated product with an acid solution, washing to neutrality, and drying to obtain the porous carbon material. In step S1, the acid solution is hydrochloric acid solution and hydrofluoric acid solution, and the pickling pretreatment comprises the steps of firstly mixing the coal gasification fine slag with 20% hydrochloric acid solution according to a solid-to-liquid ratio of 1:8-12, and then mixing the solid with 40% hydrofluoric acid solution according to the same solid-to-liquid ratio. Further, in step S2, the mass ratio of the acid washing slag, the alkali activator, the polyvinyl chloride and the polyethylene terephthalate is 1:2:0.05:1 or 1:4:0.1:1. In step S2, the alkali activ