Evaluation of graphene oxide adsorption efficiency in removing bisphenol from water

Bisphenol-A (BPA) has been widely used as a plasticizer in modern society and persistently released into aquatic environments. Herein, a novel Fe۲O۳-graphene oxide (GO) hybrid containing ۲۲.۸% of GO was prepared to enhance BPA removal from contaminated water and wastewater. This hybrid material afforded outstanding BPA adsorption capacities of ۳۲۹۳.۹ mg g۱ under optimized conditions, which led to ۱.۹ times and ۱.۲ times of BPA removal as compared to GO and reduced GO (rGO), respectively. In addition, Fe۲O۳-GO showed higher thermal stability, greater solid/liquid separation performance, and better anti-fouling performance. Moreover, the coexistence of natural or effluent organic matter caused ۶.۷-۱۶.۸% decline in BPA adsorption capacity of Fe۲O۳-GO, which was lower than those of GO and rGO (۱۱.۸-۳۹.۴%). Further characterization experiments revealed that BPA removal by Fe۲O۳-GO was enhanced because of the formation of Lewis acid-base (AB) interactions between the active sites on Fe۲O۳ (Lewis base) and BPA anions (Lewis acid). The existence of the AB interaction is beneficial for practical application considering the low environmental concentrations of BPA in water and wastewater. Besides, the distinctly lowered GO content of the hybrid saved ۷۷.۲% of the adsorbent cost. In conclusion, this study demonstrated the potential of Fe۲O۳-GO as a novel material for the treatment of BPA-contaminated water and wastewater.