Pyridinium-functionalized Ionic Porous Organic Polymer for Rapid Scavenging of Oxoanions from Water.

Abstract

Metal oxoanions adversely affect the food chain through bioaccumulation and biomagnification. Therefore, they are among the major freshwater contaminants that require immediate remediation. Although several adsorbents have been developed over the years for sequestering these micropollutants, the selective removal of oxoanions remains still a formidable challenge. Herein, pyridinium and triazine-based ionic porous organic polymer, iPOP-Cl, developed through a Brønsted acid-catalyzed aminal formation reaction, has been reported as a suitable anion exchange material for the selective removal of metal oxoanions from wastewater. The positively charged nitrogen centers, along with exchangeable chloride counter-ions in the porous polymer, allow facile oxoanion uptake. iPOP-Cl is found to be a selective scavenger of permanganate (MnO4 - ) and dichromate (Cr2 O7 2- ) from water in the presence of a high concentration of competing anions generally found in brackish water. The material exhibits fast sorption kinetics, a high uptake capacity (333mg g-1 for MnO4 - and 358mg g-1 for Cr2 O7 2- ), and excellent recyclability. This article is protected by copyright. All rights reserved.