Preparation of regenerable polymeric adsorbents functionalized with β-cyclodextrin moieties for selective recovery of bisphenol A.

Abstract Bisphenol A (BPA), widely used in polycarbonate plastics and epoxy resins, is a well-known endocrine-disrupting compound. Although numerous β -cyclodextrin (βCD)-based adsorbents for BPA removal have been reported, challenges in adsorbent synthesis and regeneration remain. This study reports the synthesis of porous polymer particles (several hundred micrometers in size) functionalized with βCD derivatives for industrial column applications. Porous polymer particles (SDG) were synthesized by suspension polymerization of styrene, divinylbenzene, and glycidyl methacrylate, yielding a specific surface area of 103.15 m²/g, as determined by mercury intrusion porosimetry. The primary hydroxy groups of βCD were brominated to obtain per(6-bromo-6-deoxy)cyclodextrin (PB-βCD). The adsorbent (SDG-EDA-βCD) was obtained via a reaction between PB-βCD and SDG aminated with ethylenediamine (EDA). Elemental analysis indicated a βCD loading of 239 µmol/g, corresponding to a theoretical BPA adsorption capacity of 54.5 mg/g. Batch adsorption experiments revealed that BPA adsorption kinetics followed the Weber–Morris model, and the maximum adsorption capacity at 293 K determined from the Langmuir isotherm was 55.6 mg/g. Repeated adsorption–desorption cycles using methanol demonstrated quantitative BPA recovery and efficient adsorbent regeneration. Thermodynamic analysis confirmed that BPA adsorption was spontaneous and exothermic, indicating that SDG-EDA-βCD is a promising adsorbent for BPA removal from aqueous media.