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CN-121988305-A - Multilayer biomass cellulose adsorption material and preparation method and application thereof

CN121988305ACN 121988305 ACN121988305 ACN 121988305ACN-121988305-A

Abstract

The invention discloses a multilayer biomass cellulose adsorption material, a preparation method and application thereof, and belongs to the technical field of biomass materials and sewage treatment. The biomass cellulose adsorption material with the sandwich multilayer structure is prepared by modifying biomass cellulose through polyethyleneimine to obtain PEI-cellulose, then crosslinking PEI-cellulose with chitosan to prepare surface adsorption liquid, simultaneously mixing unmodified biomass cellulose with polyvinyl alcohol to prepare middle-layer adsorption liquid, and finally performing liquid nitrogen freezing molding, freeze drying and alkali washing treatment layer by layer. The outer layer of the multilayer adsorption material prepared by the invention is positively charged, so that the negatively charged micro/nano plastic in water can be efficiently adsorbed by the electrostatic action, and the middle layer is neutral and can be used for adsorbing organic pollutants carried by the micro/nano plastic. The material has the advantages of low cost, simple preparation process, high adsorption rate, high removal rate and reusability, and has good application prospect in the field of water treatment.

Inventors

  • Jiang Zishuai
  • Guo Mengyi
  • YAO LIHONG
  • SHEN YULIN
  • LI ZHE
  • WANG XIAOXIN

Assignees

  • 内蒙古农业大学

Dates

Publication Date
20260508
Application Date
20260409

Claims (10)

  1. 1. The preparation method of the multilayer biomass cellulose adsorption material is characterized by comprising the following preparation steps: S1, mixing and stirring methanol solutions of biomass cellulose and polyethyleneimine for reaction, then adding glutaraldehyde solution for continuous stirring reaction, and filtering, washing and freeze-drying after the reaction is finished to obtain PEI-cellulose; s2, mixing and stirring PEI-cellulose, chitosan and glacial acetic acid solution for reaction, then adding glutaraldehyde solution, and continuing stirring for reaction to obtain solution A; S3, mixing a biomass cellulose solution and polyvinyl alcohol, performing a first stirring reaction, adjusting the pH to 4-6 after the reaction is finished, and then adding a glutaraldehyde solution for a second stirring reaction to obtain a solution B; S4, pouring the solution A into a mould, then freezing the solution A with liquid nitrogen until the surface layer is in a glassy state to obtain a first layer, continuously spreading the solution B on the surface of the first layer, performing liquid nitrogen freezing to obtain a second layer, finally continuously spreading the solution A on the surface of the second layer, performing liquid nitrogen freezing to obtain a third layer, forming a sandwich multilayer structure, and then performing integral freeze drying, soaking in sodium hydroxide solution, taking out, washing and freeze drying to obtain the multilayer biomass cellulose adsorption material.
  2. 2. The preparation method according to claim 1, wherein the ratio of the biomass cellulose, the methanol solution of polyethyleneimine and the glutaraldehyde solution in S1 is (1-2) g (100-200) mL; The concentration of the methanol solution of the polyethyleneimine is 2-6%; The concentration of the glutaraldehyde solution is 1.5-2.5 wt%.
  3. 3. The method according to claim 1, wherein the temperature of each mixing and stirring reaction in S1 is 20-25 ℃, the time is 20-24 hours, and the stirring frequency is 250-350rpm.
  4. 4. The preparation method according to claim 1, wherein the proportion of PEI-cellulose, chitosan, glacial acetic acid solution and glutaraldehyde solution in S2 is (2-6) g (5-15) g (500-1500) mL (3-9) mL; The concentration of the glacial acetic acid solution is 1-2 wt%; the concentration of the glutaraldehyde solution is 10-20 wt%.
  5. 5. The method according to claim 1, wherein the temperature of each mixing and stirring reaction in S2 is 30-50 ℃, the time is 2.5-3.5 h, and the stirring frequency is 450-550 rpm.
  6. 6. The preparation method according to claim 1, wherein the mass ratio of biomass cellulose, polyvinyl alcohol and glutaraldehyde in the step S3 is (1-2): 0.5-1.5): 0.5-1; The concentration of the biomass cellulose solution in the S3 is 1.5 wt%; The glutaraldehyde solution had a concentration of 25wt%.
  7. 7. The method according to claim 1, wherein the temperature of the first stirring reaction in S3 is 80-95 ℃ for 1.8-2.2 h and the stirring frequency is 250-350 rpm.
  8. 8. The method according to claim 1, wherein the second stirring reaction in S3 is performed at a temperature of 40-70 ℃ for a time of 25-35 min and a stirring frequency of 250-350 rpm.
  9. 9. The multi-layer biomass cellulose adsorbing material prepared by the preparation method of any one of claims 1 to 8.
  10. 10. Use of the multi-layered biomass cellulose adsorbing material according to claim 9 in sewage treatment.

Description

Multilayer biomass cellulose adsorption material and preparation method and application thereof Technical Field The invention belongs to the technical field of biomass materials and sewage treatment, and particularly relates to a multi-layer biomass cellulose adsorption material, and a preparation method and application thereof. Background The ubiquity of plastic contamination has become one of the most serious challenges for current environmental problems. Since the beginning of mass production, plastics are indispensable in modern society for their durability and versatility. However, it is these properties that make it difficult to degrade in the environment. After improper disposal, large plastic waste is degraded into Microplastic (MPs) by physical, chemical and biological processes, usually defined as plastic particles with a diameter of 5-mm and classified as nano-plastics (NPs) with a diameter of 100-nm. The ubiquitous presence of micro/nano-plastics in aquatic ecosystems (from fresh water to marine environments) constitutes a serious threat. Their microscopic dimensions make it possible for numerous organisms, ranging from zooplankton to fish, to ingest them, and in addition, the microplastic also acts as a carrier for harmful additives and hydrophobic organic pollutants, enriching and transferring them along the food chain, which, until now, has been found not only in marine organisms, but also in human feces and blood, which presents a great risk to humans and the ecological environment. In recent years, biomass material adsorbents have received increasing attention. The biomass resources such as wood, straw and the like are rich, biodegradable and renewable, and the carbon-negative material is a carbon-negative material. But the nature of biomass materials determines that they have limited adsorption capacity and are susceptible to degradation by environmental factors. In order to further improve the adsorption performance, the surface active sites and the stability of the polymer are often enhanced by chemical modification or composite functional materials. The modified wood-based adsorbent has good affinity and capturing efficiency for micro/nano plastics, and can effectively enrich charged or hydrophobic particles in water environment. In many sewage treatment technologies, the adsorption method becomes a research hot spot direction by virtue of the advantages of high efficiency, economy, simplicity and convenience in operation and the like. However, the existing sewage treatment adsorbent materials have a plurality of defects. Most adsorbent materials are selected from graphene, zeolite, carbon nano tubes and other materials with relatively high cost and complex preparation method, so that industrialization cannot be realized, secondary environmental pollution can be caused, and the recycling rate is low. The research shows that most micro/nano plastics in water environment show negative Zeta potential, and the micro/nano plastics can become carriers of certain organic pollutants, so that the pollution range is further enlarged. Therefore, in order to solve the problems, the invention provides the multifunctional adsorbent which has low cost, simple preparation flow and rich raw material resources, can realize the adsorption of micro/nano plastics and carried organic pollutants in water by changing the structural design, and has important significance for restoring polluted water bodies and protecting water environment. Disclosure of Invention In view of the above, the present invention aims to provide a multi-layer biomass cellulose adsorbing material, and a preparation method and application thereof. In order to achieve the above object, the present invention provides the following technical solutions: the invention provides a preparation method of a multi-layer biomass cellulose adsorption material, which comprises the following preparation steps: S1, mixing and stirring methanol solutions of biomass cellulose and polyethyleneimine for reaction, then adding glutaraldehyde solution for continuous stirring reaction, and filtering, washing and freeze-drying after the reaction is finished to obtain PEI-cellulose; s2, mixing and stirring PEI-cellulose, chitosan and glacial acetic acid solution for reaction, then adding glutaraldehyde solution, and continuing stirring for reaction to obtain solution A; s3, mixing a biomass cellulose solution with polyvinyl alcohol, performing a first stirring reaction, adjusting the pH to 4-6 after the reaction is finished, and performing a second stirring reaction to obtain a solution B; S4, pouring the solution A into a mould, then freezing the solution A with liquid nitrogen until the surface layer is in a glassy state to obtain a first layer, continuously spreading the solution B on the surface of the first layer, performing liquid nitrogen freezing to obtain a second layer, finally continuously spreading the solution A on the surface of the second layer, p