Removal of bisphenol A from aqueous medium using molecularly surface imprinted microbeads

The aim of this study is to prepare bisphenol A (BPA) imprinted polymers, which can be used for the selective removal of BPA from aqueous medium. The BPA-imprinted (MIP) and non-imprinted (NIP) microbeads were synthesized, and characterized by Zeta-sizer, FTIR, SEM and BET method. Bisphenol A was determined in solutions using liquid chromatography-mass spectroscopy (LC-MS). The effect of initial concentration of BPA, the adsorption rate and the pH of the medium on the capacity of BPA-imprinting polymer were studied. Adsorption capacity of BPA was affected by the amount of the incorporated functional monomer in the polymer network. BPA adsorption capacity of MIP-3 and NIP microbeads from aqueous medium was estimated as 76.7 and 59.9 mg g−1, respectively. The binding efficiencies of BPA-MIP-3 microbeads for different phenolic compounds (i.e., BPA with p-toluidine, 4-aminophenol or 2-naphthol) were explored at binary solutions, and the binding capacities of BPA-imprinted microbeads were found to be 2.79 × 10−1, 2.39 × 10−1, 7.59 × 10−2 and 5.48 × 10−2 mmol g−1 microbeads, respectively. The satisfactory results demonstrated that the obtained BPA-MIP microbeads showed an appreciable binding specificity toward BPA than similar structural compounds in the aqueous medium. Moreover, the reusability of BPA-MIP-3 microbeads was tested for several times and no significant loss in adsorption capacity was observed. Finally, the binary and multi-component systems results show that MIP-3 microbeads have special recognition selectivity and excellent binding affinity for template molecule “BPA”.