A Cyclodextrin Polymer for the Removal of Pharmaceuticals as Environmental Pollutants from Water, as Illustrated by the Example of Methylene Blue as a Model Compound

This study developed a beta-cyclodextrin polymer crosslinked with citric acid (CDCAPol) for removing water contaminants using methylene blue (MB) as a model compound. The polymer, which features free carboxyl groups and cyclodextrin cavities, demonstrated high adsorptive capacity. Under optimal conditions (0.01 g adsorbent, pH 6, and 50 mg/dm3 MB), a removal efficiency of 99.2% was achieved, with a maximum adsorption capacity of 126.58 mg/g as determined by the Langmuir isotherm. Kinetic data fit the best to the pseudo-second-order model, highlighting strong interactions between MB and the polymer. This promising material may find applications in wastewater treatment and environmental protection.