Preparation of 2-hydroxypropyl-β-cyclodextrin polymers crosslinked by poly(acrylic acid) for efficient removal of ibuprofen

In this study, 2-hydroxypropyl-b-cyclodextrin polymers crosslinked by poly(acrylic acid) were prepared through esterification reaction. The obtained polymers were characterized by Fourier transform infrared spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy, respectively. Results indicated that the 2-hydroxypropyl-b-cyclodextrin polymers were successfully prepared and crosslinked network formed in the polymers. The polymers were employed for removal of ibuprofen from aqueous solutions. The adsorption amount of ibuprofen was pH-dependent, and adsorption capacity of the polymer increased with the concentration of 2-hydroxypropyl-b-cyclodextrin in the feed formulations. The possible adsorption mechanism of the polymer towards ibuprofen involved hydrogen bonding and inclusion interactions. The ibuprofen adsorption behavior followed pseudo-second-order kinetic model and Langmuir isotherm model. Thermodynamic parameters suggested that the adsorption process was spontaneous and endothermic in nature. The polymer could be recycled and reused without any significant loss in the adsorption amount of ibuprofen. These results provided important information for designing novel adsorbents that could be employed for efficient removal of ibuprofen. (c) 2020 Elsevier B.V. All rights reserved.