Superfast removal of dyes and herbicides with triphenylamine-based porous organic polymers by one-step sulfonation and carboxylation

Abstract

The water pollution caused by modern chemical industries has become one of the most severe global environmental challenges, as an effective approach, the development of cost-effective adsorbents with rapid removal efficiency is of great significance. Herein, a simple and cost-effective post-modification synthetic strategy that includes sulfonation and carboxylation for the synthesis of porous organic polymer (POP-SO3H) was proposed, which endows POP-SO3H ultrafast adsorption rates, high adsorption capacity, and excellent reusability. For cationic dyes and herbicides including methylene blue (MB), rhodamine B (RhB), paraquat, and diquat, the removal efficiencies of POP-SO3H all reached > 96 % in only 10 s interaction and reached equilibrium within 30 s. The uptake kinetics of MB, RhB, paraquat, and diquat are 17.29, 16.12, 25.14, and 60.96 g mg−1 min−1, respectively, outperforming most of the previously reported adsorbents. Moreover, the removal efficiencies of flow-through experiments towards MB and RhB still remained > 99 % even at the flow rate of 14.7 mL min−1. This study provides a ‘one stone with two birds’ post-functionalization strategy for the preparation of cost-effective anionic adsorbents with superfast removal kinetics toward cationic pollutants.