Preparation Of Magnetic Nanomaterial Based On ?-Cyclodextrin Modification And Its Adsorption Property

The environmental burden caused by the rapid economic development has received more and more attention in recent years.The materials and methods related to environmental protection and purification have also become one of the focuses of scientists'research.Among them,water pollution removal is an important component of environmental protection.Water pollution has caused serious damage to water bodies and ecosystems,and it also threatens human survival and safety.Cyclodextrins refers to a series of cyclic oligosaccharide compounds that are transformed from starch-containing crops?raw materials?under the action of cyclodextrin glucosyltransferases.Cyclodextrins are white powders that are odorless,tasteless and crystalline in shape.They are also a common host molecule in the field of supramolecular chemistry.However,the oxygen atom on the glycosidic bond in the cyclodextrin cavity is affected by the shielding effect of the C-H bond,its polarity is very weak,and thus exhibits hydrophobicity;while the outer layer of the cavity has a large amount of hydroxyl groups,so it has the more polarity,thus showing hydrophilicity.The overall appearance present"hydrophilic outside and hydrophobic inside",so the cyclodextrins show the good adsorption ability when they adsorb the pollutants that have poor compatibility with water.Magnetic nanomaterials have advantages of large specific surface area,easy functionalization,stable properties,and easy recycling,so they possess enough space for development.This work designs various manners to modify cyclodextrins on magnetic nanoparticles,especially cyclodextrin-based ligands and cyclodextrin-based cyclodextrins.At the same time,the removal of pollutants in water has also been studied in present work.The specific research contents and results are as followings1.Preparation of magnetic metal complexes based on cyclodextrins coordination and the study of BPA adsorption performance.For the first time,a composite adsorbent material,which coated with a complex of Zn²⁺center and?-CD complex on the surface of magnetic nanoparticles was prepared.At the beginning,Fe₃O₄ nanospheres were prepared by solvothermal method.At the same time,?-CD was modified with N,N'-carbonyldiimidazole?CDI?,which had an imidazole ring.The strong interaction between Zn²⁺and N made it self-assembled.At the surface of Fe3O4 nanospheres,Fe3O4/Zn²+/CD-CDI composites were obtained,and the material was applied to study the adsorption properties of BPA in water.The results show that Fe3O4/Zn²⁺/CD-CDI composites have relatively high removal rate to BPA and high recovery and good recyclability.Therefore,the application of Fe₃O₄/Zn²⁺/CD-CDI composite materials in environmental protection will have a good application prospect.2.Novel porous magnetic nanomaterial functionalized by?-cyclodextrin polymer and its application in the rapid removal of organic pollutants from water.A novel monodisperse P-MCD nanoparticle was successfully prepared by solvothermal method for MB extraction.The P-MCD material combines the characteristics of nuclear Fe3O4that has fast magnetic separation response and superficially porous?-CD polymers.The polymer has a fast kinetics and a wide range of adsorption of organic micro-pollutants.The rapid kinetics of the material may be due to the large surface area and the large number of cyclodextrin cavities.At the same time,nanoparticles also have high recovery and good recyclability.Therefore,the MB can be quickly separated from the actual water sample using P-MCD nanoparticles.P-MCD nanoparticles are expected to be promising materials for environmental applications.