Removal of bisphenol A from water solution using molecularly imprinted nanopolymers: isotherm and kinetic studies

In the present study, adsorption behavior of mesoporous molecularly imprinted polymers for bisphenol A was investigated. Molecularly imprinted nanopolymers were synthesized by precipitation polymerization using bisphenol A as a template molecule. Two molecular ratios of templet: functional monomer: cross-linker (1:6:30 (MIP-6) and 1:4:20 (MIP-4)) was considered for experiments. Ethylene Glycol Dimethacrylate (EGDMA) as a Crosslinker, metacrylic acid (MAA) as a functional monomer and 2, 2´-azobisisobutyronitrile (AIBN) as an initiator were used for the synthesis of polymers. In addition, Langmuir and Freundlich adsorption isotherms and pseudo-first-order and pseudo-second-order kinetic models were studied for adsorption mechanism. Results showed that porous polymers with average pore diameter of 13 to 17 nm and specific surface area of 326 to 439 (cm3/g) were obtained. The maximum adsorption capacity was 400.1 μmol/g for MIP-6. SEM analysis showed that the synthesized polymer particles were spherical. The highest adsorption efficiency of bisphenol A achieved by MIP-6 was 71%.