Recovery of Bisphenol A by pH-Triggered Magnetic Nanoparticles

Abstract

Bisphenol A is not only one of the frequent contaminants of industrial wastewater, but also one of the main ingredients in polycarbonate and epoxy resins. This study synthesizes a pH-triggered Fe3O4@mSiO2@DPDES adsorbent for recycling Bisphenol A through adsorption–desorption process. Due to the strong [Formula: see text]–[Formula: see text] interaction between the phenyl groups in diphenyldiethoxysilane modified magnetic nanoparticles (MNPs) and Bisphenol A, absorbance reached 120.17[Formula: see text]mg/g at pH 7, allowing the bisphenol A adsorbed to Fe3O4@mSiO2@DPDES to be trivially separated from aqueous solutions with a magnet. Desorption of the adsorbed bisphenol A in aqueous solution occurred at pH 2, allowing an impressive 95% recovery rate. The durability of the Fe3O4@mSiO2@DPDES adsorbent was tested by repeated separation of bisphenol A from an aqueous solution, with the recovery efficiency remaining greater than 85% after five cycles.