Highly efficient removal of bisphenols from aqueous solution using environmental-sensitive microgel

Abstract

A temperature and pH sensitive microgel was synthesized and applied for sorption of five bisphenols (bisphenol A (BPA), bisphenol B (BPB), bisphenol E (BPE), bisphenol F (BPF) and bisphenol S (BPS)) from aqueous solutions. The microgel was synthesized from methacrylate derivatives of poly(ethylene glycol) and acrylic acid using the precipitation polymerization method. Liquid chromatography with UV detection (LC-UV) was used for the quantification of bisphenols. The microgel appeared to be a satisfactory sorbent. The maximum experimental adsorption capacities obtained for all five bisphenols were between two values: 55 mg g−1 and 160 mg g−1. The sequence of bisphenols absorption was the following BPS<BFP<BPE<BPA<BPB. Kinetics of sorption, effects of pH and temperature on sorption capacity were also investigated. The experimental data were well described by the pseudo-second order kinetic model and fitted well the adsorption Langmuir model. Using the analysis of the Langmuir model we reached the maximum sorption capacity of 70 mg g−1 to 210 mg g−1. The microgel can be regenerated effectively using an organic solvent; the adsorption capacity remained constant after multiple times of gel uses. The proposed microgel is a promising sorbent for reasonably fast adsorption of bisphenols (BPs) and might be used for the determination of very low concentrations of BPs present in water.