Removal of bisphenol A from aqueous media using a highly selective adsorbent of hybridization cyclodextrin with magnetic molecularly imprinted polymer

• Main Authors: Mamman, S., Suah, F. B. M., Ramachandran, Muggundha Raoov, Mehamod, F. S., Asman, S., Zain, N. N. M.
• Format: Article
• Published: The Royal Society 2021
• Subjects: QD Chemistry
• Online Access: http://eprints.um.edu.my/28522/
• Institution: Universiti Malaya

In this study, a unique magnetic molecularly imprinted polymer (MMIP) adsorbent towards bisphenol A (BPA) as a template molecule was developed by bulk polymerization using beta-cyclodextrin (beta-CD) as a co-monomer with methacrylic acid (MAA) to form MMIP MAA-beta CD as a new adsorbent. beta-CD was hybridized with MAA to obtain water-compactible imprinting sites for the effective removal of BPA from aqueous samples. Benzoyl peroxide and trimethylolpropane trimethacrylate were used as the initiator and cross-linker, respectively. The adsorbents were characterized by Fourier transform infrared spectroscopy, scanning electronic microscopy, transmission electron microscopy, vibrating sample magnetometer, Brunauer-Emmett-Teller and X-ray diffraction. H-1 nuclear magnetic resonance spectroscopy was used to characterize the MAA-beta CD and BPA-MAA-beta CD complex. Several parameters influencing the adsorption efficiency of BPA such as adsorbent dosage, pH of sample solution, contact time, initial concentrations and temperature as well as selectivity and reusability study have been evaluated. MMIP MAA-beta CD showed significantly higher removal efficiency and selective binding capacity towards BPA compared to MMIP MAA owing to its unique morphology with the presence of beta-CD. The kinetics data can be well described by the pseudo second-order kinetic and Freundlich isotherm and Halsey models best fitted the isotherm data. The thermodynamic studies indicated that the adsorption reaction was a spontaneous and exothermic process. Therefore, MMIP based on the hybrid monomer of MAA-beta CD shows good potential of a new monomer in molecularly imprinted polymer preparation and can be used as an effective adsorbent for the removal of BPA from aqueous solutions.