Highly efficient adsorption and removal of phthalate esters by polymers of intrinsic microporosity

In recent years, phthalate esters (PAEs) have been found to be endocrine disruptors that pose a serious safety threat to human health. Currently, adsorption is one of the most efficient technologies to remove PAEs, and the development of adsorbent materials that combine high adsorption capacity and short equilibrium time is a challenging problem. In this study, PIM-1, a typical representative of polymers of intrinsic microporosity (PIMs), was prepared through three methods and first used as adsorbents for PAEs removal. PIM-1 prepared under high temperature (HT-PIM-1) exhibited a high capacity of 787 mg/g for dibutyl phthalate (DBP), a prevalent PAE in water, which is significantly higher than most reported adsorbents. Furthermore, more than 90.0 % of the equilibrium adsorption capacity can be reached within 30 mins. In addition, the adsorption of DBP could be inhibited by ethanol due to the enhanced interaction between DBP and ethanol, which could be revealed by molecular simulation. The adsorption mechanism of PAEs on PIM-1 mainly included hydrophobic interactions, π-π interactions, together with the size matching between PAEs and hierarchical pores of PIM-1. This study provides an idea for the application of PIMs for PAEs removal with high adsorption capacity and high efficiency.