Environmentally friendly fabrication of new β-Cyclodextrin/ZrO2 nanocomposite for simultaneous removal of Pb(II) and BPA from water

Heavy metals and endocrine disrupters often co-exist in wastewater, while their possible competition behaviours make uptake removal more challenging. Therefore, beta-Cyclodextrin based nanocomposite adsorbent was successfully fabricated (beta-Cyclodextrin/ZrO2) for the simultaneous uptake of Pb(II) and Bisphenol A from wastewater. FTIR, XRD, and XPS confirmed the successful fabrication of the beta-Cyclodextrin/ZrO2 nanocomposite. In this setting, oxygen-containing groups are primarily responsible for the Pb(II) binding, while the beta-Cyclodextrin cavities adsorb Bisphenol A through host-guest interaction, enabling the simultaneous removal of Pb(II) and Bisphenol A. In the mono contaminant system, the nanocomposite displayed prominent removal ability toward Pb(II) and Bisphenol A with adsorption characteristics of pseudo-second-order, Langmuir, and Freundlich isotherm model. The maximum adsorption capacities were identified for Pb(II) and Bisphenol A to be 274.4 mg/g and 174.9 mg/g at 298 K, respectively. Most importantly, the beta-Cyclodextrin/ZrO2 could efficiently attain simultaneous removal of Pb(II) and Bisphenol A by avoiding their competitive behaviours was due to the different adsorption mechanisms (electrostatic interaction and host-guest interaction). Moreover, the adsorbed Pb(II) and Bisphenol A could be successfully recovered with a slight decline in nanocomposite removal performance even after 4 cycles in the binary-component system. All these findings provide insights into the fabrication of highly effective adsorbent with separated adsorption sites to treat wastewater bearing heavy metal and endocrine disrupters. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

A beta-Cyclodextrin/ZrO2 nanocomposite adsorbent was successfully fabricated for the simultaneous uptake of Pb(II) and Bisphenol A from wastewater. The adsorbent showed efficient removal performance with different adsorption mechanisms, enabling the simultaneous removal of the contaminants. Moreover, the adsorbed pollutants could be successfully recovered with only a slight decline in the nanocomposite's removal performance even after multiple cycles.