The synthesis of a DMpillar[5]arene-based porous polymer with ultrafast adsorption rate and high adsorption capacity for organic micropollutants from water

Abstract

Organic micropollutant in the aquatic environment has become a worldwide problem. In this study, a new DMpillar[5]arene-based porous organic polymer (DMPBP[5]) with the highest surface area of 1347.4 ± 39.3 m2 g−1 is developed through Friedel-Crafts alkylation reaction between DMpillar[5]arene (DMP5) and 4,4′-bis(chloromethyl)-1,1′-biphenyl (BCMBP) to remove a wide range of organic micropollutants with fast removal rate and large uptake amounts. The synthesized DMPBP[5] can capture many types of organic pollutants in water including positively charged, negatively charged and neutral ones and those with different hydrophilicity, through host–guest interaction, hydrophobic interaction, electrostatic interaction and π-π interaction. For some pollutants, the adsorption kinetic constants of DMPBP[5] are thousands of times larger than that of activated carbon (AC) and even 104-105 times larger than that of resin (XAD-4), and the adsorption capacities of DMPBP[5] are about 3 and 4 times higher than that of AC and XAD-4, respectively. The superior adsorption performance of DMPBP[5] is attributed to permanent porosity and accessible binding sites because of the introduction of rigid structure. Even at environmentally relevant concentrations, DMPBP[5] can quickly remove the pollutants simultaneously and can be easily regenerated with methanol under ambient conditions. In short, due to the wide adsorption range, excellent adsorption performance, and easy recyclability, DMPBP[5] is an excellent adsorbent for wastewater treatment with great application potential.