Porous Polymer Adsorbents of Tris(4-formylphenyl)amine and β-Cyclodextrin for Endocrine-Disrupting Chemicals, Dyes, and Antibiotics

The complexity of pollutants in water, including endocrine-disrupting chemicals, dyes, and antibiotics, poses a challenge to existing water treatment agents. Therefore, we successfully cross-linked tris(4-formylphenyl)amine (TFPA) onto β-cyclodextrin (β-CD) to synthesize a β-cyclodextrin polymer (TFPA-N-β-CD). This unique adsorbent provides essential adsorption properties from each of its components: β-CD offers a cavity structure and hydrophilic groups capable of removing organic micropollutants through host–guest interactions, while TFPA not only constructs a three-dimensional network structure to enhance the specific surface area (63.68 m 2 /g) but also provides adsorption sites. In single-component systems, the adsorption of bisphenol A (BPA), methylene blue (MB), and tetracycline (TC) follows the pseudo-second-order kinetic model and the Sips adsorption isotherm model. The maximum adsorption capacities are 164.73 (BPA), 272.03 (MB), and 33.89 mg/g (TC). In binary system mixed adsorption, each pollutant still maintains significant adsorption capacity, with adsorption capacity ratios ( R q ) greater than 0.80. This reveals the different mechanisms behind the adsorption of TFPA-N-β-CD. During the adsorption of BPA, host–guest interactions dominate, while electrostatic forces are stronger than hydrophilic and inclusion interactions in MB adsorption, and hydrophilic interactions play a dominant role in TC adsorption. Additionally, after 10 consecutive adsorption–desorption cycles, the adsorption capacity of TFPA-N-β-CD for the target pollutants was maintained at over 55% of its initial value, demonstrating its excellent cycling stability and potential for reuse. These characteristics make it highly promising for the treatment of complex real wastewater.