Thioether-functionalized porous β-cyclodextrin polymer for efficient removal of heavy metal ions and organic micropollutants from water

Herein, a thioether-functionalized porous β-cyclodextrin polymer (P(Bn-S-CD)) was prepared for efficient removal of heavy metal ions and organic micropollutants (OMPs) from water. P(Bn-S-CD) showed a surface area of 763 m2/g and a sulfur content 5.83 wt%. Based on screening studies, Hg2+ and diclofenac sodium (DS) were selected as model pollutants. P(Bn-S-CD) could adsorb Hg2+ and DS simultaneously, while the adsorbed Hg2+ afforded positive charges to the primary rims of CDs, greatly enhancing the adsorption rate and adsorption capacity of DS. Although the adsorbed DS showed no obvious effect on Hg2+ adsorption, it improved the affinity of Hg2+ upon P(Bn-S-CD). Adsorption mechanism studies confirmed the essential role of electrostatic interactions for these results. P(Bn-S-CD) also showed good selectivity towards heavy metal ions, excellent adsorption performance in real water at environmental levels and good reusability, implying great promise for water treatment.