Magnetically hyper-cross-linked polymers with well-developed mesoporous: a broad-spectrum and highly efficient adsorbent for water purification

A novel magnetically hyper-cross-linked polymer (Fe 3 O 4 @HCP-NH 2 ) was prepared in this study, which combined the advantage of the amino-modified HCP-NH 2 and the magnetic Fe 3 O 4 nanoparticles. The Fe 3 O 4 @HCP-NH 2 composite has a high specific surface area (532.62 m 2  g −1 ), well-developed mesoporous (0.3786 cm 3  g −1 ) and good magnetic property. This Fe 3 O 4 @HCP-NH 2 composite exhibits excellent adsorption ability for tetracycline, and the maximum adsorption capacity calculated by Langmuir model at 298 K is up to 694 mg g −1 . The adsorption mechanisms could be attributed to the complexation interactions, hydrogen bonding and cation exchange, and the dominant interaction was the surface complexation which was elucidated by X-ray photoelectron spectroscopy analysis. In addition, the composite can be rapidly separated and maintains high adsorption performance after five regeneration cycles. More importantly, it can be used as a broad-spectrum and highly efficient adsorbent for organic contaminants including methyl orange, methylene blue, bisphenol A and 2,4-dichlorophenol removal from contaminated water. This work demonstrated that the Fe 3 O 4 @HCP-NH 2 composite would be the most promising candidates for application in the adsorption of organic pollutants.