A novel carbon adsorbent derived from iron-poisoned waste resin for phosphate removal from wastewater: Performance and mechanism.

In this study, a new Fe-rich carbon composite derived from iron-poisoned waste resin (WRC) was successfully prepared via pyrolysis-activation to remove phosphate from wastewater. The physicochemical properties of WRC were characterized using multiple characterization tools. The results showed that the WRC had a large specific surface area and was rich in metal loading for adsorption. Batch and fixed-bed experiments investigated the adsorption performance of WRC. The maximum adsorption capacity calculated from the Langmuir model was 17.43 mg/g at 298 K. Kinetics experiments showed that the adsorption of phosphate by WRC accorded with pseudo-second-order kinetic model. The WRC could maintain excellent adsorption performance in a wide pH range of 2–12, suitable for various wastewater conditions. Meanwhile, the WRC had well anti-interference of common anions and humic acids on phosphate adsorption and WRC reuse performance. The mechanisms of phosphate adsorption by WRC were confirmed to be electrostatic attraction, ligand exchange and Lewis acid-base interaction. Fixed bed experiments were conducted for dynamic treatment of synthetic wastewater and actual wastewater, and the results indicated that WRC had potential application prospect. This study provides an economically feasible method for the phosphate removal from wastewater and achieves the reuse of waste resin. [Display omitted] [ABSTRACT FROM AUTHOR]