ZIF-8-derived N-doped hierarchical porous carbon coated with imprinted polymer as magnetic absorbent for phenol selective removal from wastewater

Producing a desirable adsorbent with strong affinity adsorption sites, excellent selectivity properties, and the ability to easily separate solid from liquid for the removal of phenol to a permissible level remains a great challenge in wastewater treatment. Herein, an N-doped magnetic carbon skeleton is presented as a porous adsorbent matrix. Importantly, the pore volume and specific surface area of the adsorbent matrix can be meticulously tuned by adjusting the thermal treatment condition, while dispersing and immobi-lizing the N fraction. This would ultimately result in an N-rich matrix structure with flexible mass transfer channel. The imprinted modification generates a large number of phenol-shaped geometrical cavities on the matrix. This helps to activate the phenol recognition awareness of N-active sites and greatly endows the adsorbent with selective adsorption property. Due to the advantageous balance between the hierarchical porous adsorbent matrix with uniformly distributed N-active sites and the imprinted polymer, the adsorbent has a superior adsorption capacity of 995.2 mg g(-1) and selective recognition (K-d = 3.92, 3.78; HQ, PTBP) towards phenol. It outperforms previously reported adsorbents. In addition, its easy magnetic separation property makes the adsorbent to have excellent reusability. The adsorbent presents a promising potential for separating pollutants from wastewater and it sheds light on the design of an efficient comprehensive adsorbent. (C) 2022 Elsevier Inc. All rights reserved.

Automated summary

In this study, an N-doped magnetic carbon skeleton was developed as a porous adsorbent matrix with strong affinity adsorption sites and excellent selectivity properties for the removal of phenol from wastewater. By adjusting the thermal treatment condition, the pore volume and specific surface area of the adsorbent matrix could be finely tuned, resulting in an N-rich matrix structure with flexible mass transfer channel. The imprinted modification created phenol-shaped geometrical cavities on the matrix, activating the phenol recognition of N-active sites and providing selective adsorption property. The adsorbent demonstrated superior adsorption capacity and selective recognition towards phenol, outperforming previously reported adsorbents. Its easy magnetic separation property also allowed for excellent reusability. This adsorbent shows promising potential for separating pollutants from wastewater and contributes to the design of efficient comprehensive adsorbents.