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CN-121990573-A - Alkali metal modified waste plastic-based porous carbon and preparation method thereof

CN121990573ACN 121990573 ACN121990573 ACN 121990573ACN-121990573-A

Abstract

The invention discloses a waste plastic-based porous carbon and a preparation method thereof, wherein waste plastic and medical waste incineration slag are taken as raw materials, the waste plastic and medical waste incineration slag are respectively crushed to obtain raw material particles with a certain mesh, then the waste plastic particles are carbonized at a high temperature to obtain waste plastic-based pyrolytic carbon, the medical waste incineration slag particles are subjected to acid treatment, and then the waste plastic-based pyrolytic carbon and the medical waste incineration slag particles are mixed, ball-milled and co-activated at a high temperature to enable alkali metal components in the slag to be chemically loaded on the surfaces of the carbon particles, so that the alkali metal modified waste plastic-based porous carbon is obtained. The invention uses solid waste as a basic raw material, has simple synthetic route, does not need expensive equipment/chemical reagents, greatly reduces the running cost, ensures the large-scale production, and ensures that the obtained porous carbon has good adsorption performance on volatile organic compounds.

Inventors

  • ZHONG YANFEI

Assignees

  • 上海莫兰迪环境科技有限公司

Dates

Publication Date
20260508
Application Date
20260207

Claims (10)

  1. 1. A method for preparing alkali metal modified waste plastic-based porous carbon, which is characterized by comprising the following steps: (1) Respectively preprocessing waste plastics and medical waste incinerator slag; (2) Carbonizing the waste plastics pretreated in the step (1) at high temperature to obtain waste plastic-based pyrolytic carbon; (3) Carrying out acid treatment on the medical waste incinerator slag pretreated in the step (1); (4) Mixing the waste plastic-based pyrolytic carbon obtained in the step (2) with the medical waste incineration slag subjected to acid treatment in the step (3), performing ball milling, and performing high-temperature coactivation to enable alkali metal components in the medical waste incineration slag to be chemically loaded on the surfaces of the waste plastic-based pyrolytic carbon particles, and then sequentially performing acid washing, water washing and drying on the products to obtain the waste plastic-based porous carbon.
  2. 2. The method for preparing the waste plastic-based porous carbon according to claim 1, wherein the pretreatment of the waste plastic in the step (1) is to cool and crush the waste plastic in liquid nitrogen to obtain waste plastic particles with 80-100 meshes.
  3. 3. The method for preparing the waste plastic-based porous carbon according to claim 1, wherein the pretreatment of the medical waste incineration slag in the step (1) is to crush the medical waste incineration slag into slag particles of 120-150 meshes, the content of SiO 2 in the medical waste incineration slag is lower than 35%, and the total content of Na 2 O and K 2 O is higher than 6%.
  4. 4. The method for producing a waste plastic-based porous carbon according to claim 1, wherein the high-temperature carbonization in step (2) is performed under a nitrogen atmosphere at a carbonization temperature of 400 to 500 ℃ for 30 to 120 minutes.
  5. 5. The method for preparing the waste plastic-based porous carbon according to claim 1, wherein the acid treatment in the step (3) is carried out by adopting hydrofluoric acid solution, the volume concentration of the hydrofluoric acid solution is 5-10%, the use amount of the hydrofluoric acid solution is converted according to the water content of 25-45% in the infiltrated slag, and the infiltration time is 2-4 hours.
  6. 6. The method for producing a waste plastic-based porous carbon according to claim 1, wherein the mass ratio of the acid-treated medical waste incinerator slag in the mixture is 15 to 25% in the mixing in the step (4).
  7. 7. The method for preparing waste plastic-based porous carbon according to claim 1, wherein the ball milling time in the step (4) is 2-6 hours.
  8. 8. The method for preparing the waste plastic-based porous carbon according to claim 1, wherein in the step (4), high-temperature CO-activation is performed by using water vapor or CO 2 as an activating agent and N 2 as a carrier gas, wherein the volume content of the water vapor or CO 2 is 5-25%, the activating temperature is 600-800 ℃, and the activating time is 30-120 min.
  9. 9. The method for producing a waste plastic-based porous carbon according to claim 1, wherein the drying temperature in step (4) is 100 to 110 ℃ for 12 to 24 hours.
  10. 10. An alkali metal modified waste plastic-based porous carbon produced by the method of any one of claims 1 to 9.

Description

Alkali metal modified waste plastic-based porous carbon and preparation method thereof Technical Field The invention belongs to the technical field of porous carbon material preparation, and particularly relates to alkali metal modified waste plastic-based porous carbon and a preparation method thereof. Background Volatile organic contaminants are a very important class of contaminants in the atmospheric environment, and are key precursors for the formation of PM 2.5 and ozone. In the aspect of human health hazard, the volatile organic pollutants have pungent odor, can directly stimulate the skin and eyes of a human body, damage the nervous system and the respiratory system, and bring great hazard to human health. Therefore, emission reduction of volatile organic compounds is receiving increasing attention. The source of the volatile organic compounds is wide, more low-concentration emission sources exist in engineering practice, such as electronic product production, small-sized automobile maintenance workshops and the like, and the emission quantity of the volatile organic compounds is greatly improved. There are many methods for removing volatile organic compounds, including absorption, adsorption, catalytic oxidation, membrane separation, catalytic combustion, biodegradation, etc., wherein the adsorption method is the method for efficiently removing low-concentration organic pollutants and has the most application prospect. Carbon-based adsorbents are a class of adsorbent materials that have the widest range of applications, particularly activated carbon. However, conventional commercial activated carbon mainly uses graphite surface, has weak adsorption force on volatile organic compounds, and especially has limited adsorption performance on polar volatile organic compounds. Therefore, in order to improve the adsorption performance, the surface of the activated carbon is usually subjected to modification treatment such as acid treatment, metal ion modification and heteroatom loading, but most of the modification processes are complicated, a large amount of byproducts are produced, the cost is high, and the large-scale industrial preparation is not facilitated. Therefore, development of a carbon-based adsorption material with low cost and high adsorption performance is helpful for ensuring efficient removal of volatile organic compounds with low concentration. Disclosure of Invention Aiming at the defects of the prior art, the invention provides the alkali metal modified waste plastic-based porous carbon and the preparation method thereof, which can be applied to the efficient adsorption removal of low-concentration polar volatile organic pollutants, and provide a new method for solving the problems of high preparation cost and low organic pollutant removal efficiency of the functionalized carbon material. In order to achieve the above purpose, the invention adopts the following technical scheme: One of the objects of the present invention is to protect a method for preparing an alkali metal modified waste plastic-based porous carbon, comprising the steps of: (1) Respectively preprocessing waste plastics and medical waste incinerator slag; (2) Carbonizing the waste plastics pretreated in the step (1) at high temperature to obtain waste plastic-based pyrolytic carbon; (3) Carrying out acid treatment on the medical waste incinerator slag pretreated in the step (1); (4) Mixing the waste plastic-based pyrolytic carbon obtained in the step (2) with the medical waste incineration slag subjected to acid treatment in the step (3), performing ball milling, and performing high-temperature coactivation to enable alkali metal components in the medical waste incineration slag to be chemically loaded on the surfaces of the waste plastic-based pyrolytic carbon particles, and then sequentially performing acid washing, water washing and drying on the products to obtain the waste plastic-based porous carbon. Further, the waste plastics in the step (1) mainly refer to high molecular polymers with oxygen-containing elements, and the high molecular polymers comprise polyethylene terephthalate, polycarbonate, phenolic resin, polyurethane and the like. Further, in the step (1), the waste plastics are pretreated by cooling and crushing the waste plastics in liquid nitrogen to obtain waste plastics particles with 80-100 meshes. Further, the medical waste incineration slag in the step (1) is slag generated after incinerating incineratable medical waste including infectious waste, damaging waste, pathological waste, pharmaceutical waste and chemical waste, the content of SiO 2 is less than 35%, and the total content of Na 2 O and K 2 O is more than 6%. Further, in the step (1), the medical waste incineration slag is pretreated by crushing the medical waste incineration slag into slag particles of 120-150 meshes. Further, the high-temperature carbonization in the step (2) is performed under a nitrogen atmosphere, the carbonization