New Viologen-Based Ionic Porous Organic Polymers for Efficient Removal of Anionic Dyes and Hexavalent Chromium (Cr (VI)) from Water

Water pollution is a critical environmental issue in modern society, and adsorption is recognized as a straightforward and efficient water purification technique. In this study, three new viologen-based ionic porous organic polymers were designed and successfully synthesized via a simple approach, and their adsorption properties for water pollutants were evaluated. The cationic nature of these polymers, coupled with their large conjugated π-electron system, physicochemical stability, and aromatic backbone, contributes to their high adsorption capacity and rapid adsorption efficiency for anionic contaminants in water such as Methyl Orange, Congo Red, and Cr (VI). The polymers exhibited maximum adsorption capacities of 1617 mg/g for MO, 3734 mg/g for CR, and 530.22 mg/g for Cr (VI), surpassing most previously reported adsorbents. Furthermore, the polymers maintained a high removal rate even in the presence of competing anions. Effective separation of anionic dyes from mixed solutions could be achieved through simple filtration. These characteristics make them promising candidates for water purification applications.