CN-119684540-B - Lignin doped montmorillonite hydrogel and preparation method and application thereof

CN119684540BCN 119684540 BCN119684540 BCN 119684540BCN-119684540-B

Abstract

The invention relates to lignin doped montmorillonite hydrogel, a preparation method and application thereof, and belongs to the field of functional materials. A method for preparing lignin doped montmorillonite hydrogel comprises the steps of sequentially adding montmorillonite k-10, methacryloxyethyl trimethyl ammonium chloride, acrylic acid, acrylamide, N, N-methylenebisacrylamide and potassium persulfate into an aminated lignin aqueous solution, uniformly stirring, and carrying out free radical polymerization reaction, wherein the obtained product is soaked in deionized water to obtain the lignin doped montmorillonite hydrogel. The method for preparing the lignin doped montmorillonite hydrogel is a one-step method, has simple process and low production cost, and is more suitable for large-scale industrial utilization. The lignin doped montmorillonite hydrogel prepared by the invention contains rich active sites, has strong adsorption capacity to nitrogen and phosphorus ions and microplastic, and can adsorb the nitrogen and phosphorus ions and the microplastic at the same time.

Inventors

GUO YANZHU
ZHANG YIHAO
CHU TINGTING
HU PENGYU
LEI LONGWEN
MA LAN
WANG XING
LI HAIMING

Assignees

大连工业大学

Dates

Publication Date: 20260508
Application Date: 20241226

Claims (9)

1. A preparation method of lignin doped montmorillonite hydrogel is characterized in that montmorillonite k-10, methacryloxyethyl trimethyl ammonium chloride, acrylic acid, acrylamide, N, N-methylenebisacrylamide and potassium persulfate are sequentially added into an aminated lignin aqueous solution, the mixture is stirred uniformly, free radical polymerization reaction is carried out, the obtained product is soaked in deionized water, and the lignin doped montmorillonite hydrogel is obtained, wherein the mass volume ratio of aminated lignin to deionized water in the aminated lignin aqueous solution is 0.15-g mL, the mass ratio of aminated lignin k-10, methacryloxyethyl trimethyl ammonium chloride, acrylic acid, acrylamide, N, N-methylenebisacrylamide and potassium persulfate is 0.15-0.15 g:0.5-1.5 g, 1.0-3.0 g, 0.5-1.5 g, 0.01-0.09 g and 0.01-0.03 g.
2. The method of claim 1, wherein the radical polymerization reaction is carried out at 40-80 ℃ for 1-3 hours.
3. The method of claim 1, wherein the product is immersed in deionized water for 20-40 hours.
4. The lignin-doped montmorillonite hydrogel prepared by the method of any one of claims 1-3.
5. Use of the lignin-doped montmorillonite hydrogel according to claim 4 for adsorbing nitrogen ions and/or phosphorus ions and/or microplastic.
6. The method according to claim 5, wherein the lignin-doped montmorillonite hydrogel is mixed with an aqueous solution of nitrogen ions and/or phosphorus ions and/or microplastic, the mixture is adsorbed in a shaker, and after the adsorption, the solid sample is filtered by suction to obtain the lignin-doped hydrogel after adsorbing the nitrogen ions and/or phosphorus ions and/or microplastic.
7. The method of claim 6, wherein the adsorption is carried out at a temperature of 20-40 ℃ at 100-200 rpm for 10-600 min.
8. The use according to claim 6, characterized in that: The nitrogen ion aqueous solution is one or more of an ammonium chloride solution, an ammonium sulfate solution and an ammonium nitrate solution; The phosphorus ion aqueous solution is one or more of potassium dihydrogen phosphate solution, dipotassium hydrogen phosphate solution and sodium dihydrogen phosphate solution; The micro plastic aqueous solution is one or more of polystyrene solution, polypropylene solution and polyethylene solution.
9. The use according to claim 6, characterized in that: the concentration of the nitrogen ion aqueous solution is 10-200 mg N/L, the concentration of the phosphorus ion aqueous solution is 10-200 mg P/L, and the concentration of the micro plastic aqueous solution is 100-1000 mg/L; the mass volume ratio of the lignin doped montmorillonite hydrogel to the nitrogen ion and/or phosphorus ion and/or microplastic aqueous solution is 0.05 g:10-100 mL.

Description

Lignin doped montmorillonite hydrogel and preparation method and application thereof Technical Field The invention relates to lignin doped montmorillonite hydrogel, a preparation method and application thereof, and belongs to the field of functional materials. Background Nitrogen and phosphorus are essential elements for all living organisms in nature. However, various nitrogen and phosphorus-containing wastewater discharged for a long time in industrial and agricultural production causes serious eutrophication of natural water bodies, thereby seriously damaging aquatic ecosystems. Therefore, the efficient removal and recycling of nitrogen and phosphorus pollutants in water has become a key to solve the problems of current eutrophication water treatment and sustainable utilization of nitrogen and phosphorus resources. Also, with the wide use of plastic products, microplastic is widely present in environmental media and living organisms worldwide, and has wide sources, widespread distribution, complex environmental behaviors, and potential ecotoxicological effects, which pose a serious threat to the ecosystem and human health. Therefore, the realization of efficient removal and recycling of the microplastic in the waste water containing the microplastic is very important. Hydrogels are considered as a potential candidate material for wastewater treatment in addition to conventional adsorbents such as zeolite, clay minerals, synthetic resins, and activated carbon. Generally, hydrogels have good hydrophilicity, large specific surface area, and a large number of porous structures and active adsorption groups or sites, which ultimately lead to strong interactions between contaminant ions and active adsorption sites, thereby improving the removal efficiency of contaminants in wastewater. Natural polymers in biomass, such as lignin, cellulose, chitosan and the like, are widely used as raw materials for preparing hydrogel due to the characteristics of rich content, environmental friendliness, biodegradability and the like, so that the hydrogel is endowed with good environmental characteristics. Lignin, one of the main chemical components, is widely present in plants and is a three-dimensional network natural polymer with an aromatic structure. At the same time, lignin structures contain a large number of reactive functional groups, such as carboxyl, phenolic and aliphatic hydroxyl groups, which make lignin easy to process into hydrogels or impart limited adsorption capacity to lignin materials. Lignin is considered to be an ideal polymer for preparing hydrogels because the use of hydrogels not only brings high value to lignin, but also contributes to cost reduction and improvement of the mechanical properties of hydrogels. In addition, it has been demonstrated that eutrophic wastewater often contains both anions and cations as well as micro-plastics and other contaminants, while lignin-doped hydrogel adsorbents containing only one ionic group cannot remove all contaminants, and thus cannot meet the actual utilization needs. Therefore, the preparation of the polynary lignin doped montmorillonite hydrogel for simultaneously recycling nitrogen, phosphorus and microplastic in wastewater has important significance. However, the early preparation of amphoteric lignin-based hydrogels is relatively complex and typically requires two or more synthesis steps. Firstly, lignin is taken as a raw material to synthesize a water-soluble lignin derivative, then the lignin derivative is modified, and different groups are introduced to obtain the amphoteric lignin-based hydrogel. This complex synthesis step is not conducive to large scale popularization of the amphoteric lignin-based hydrogels in industrial synthesis. Therefore, a simple and convenient synthesis method for preparing amphoteric lignin-based hydrogel needs to be found. The lignin doped montmorillonite hydrogel is prepared by a one-step chemical modification process, is environment-friendly, efficient, stable and economic, and is used for efficiently removing nitrogen and phosphorus ions and microplastic in a water body. Disclosure of Invention Aiming at the defects existing in the process of preparing pollutant adsorption materials in the prior art, the invention provides lignin doped montmorillonite hydrogel, and a preparation method and application thereof. According to the invention, lignin is used as a raw material, montmorillonite k-10, methacryloxyethyl trimethyl ammonium chloride, acrylic acid and acrylamide are used as monomers, potassium persulfate is used as an initiator, N, N-methylene bisacrylamide is used as a cross-linking agent, and the lignin doped montmorillonite hydrogel capable of adsorbing nitrogen and phosphorus ions and microplastic pollutants is prepared through free radical polymerization, so that the production cost is low, and the application prospect is good. A method for preparing lignin doped montmorillonite hydrogel comprises the steps of