Issue 4, 2022

Preparation of magnetic covalent triazine frameworks by ball milling for efficient removal of PFOS and PFOA substitutes from water

Abstract

Difficult separation of covalent organic frameworks (COFs) greatly limits their application in wastewater treatment. For the first time, the ball-milling method was used to prepare recyclable magnetic covalent triazine frameworks (CTF/Fe3O4), and little influence on the structure and adsorption performance of CTFs after ball-milling was observed. We synthesized crystalline CTF1 and amorphous CTF2 materials and then investigated the effect of CTF/Fe3O4 mass ratios on the removal of two typical PFOS and PFOA substitutes including sodium p-perfluorous nonenoxybenzene sulfonate (OBS) and hexafluoropropylene oxide trimer acid (HFPO-TA). CTF2/Fe3O4 exhibited higher adsorption performance than CTF1/Fe3O4 due to the additional quaternary amine groups as highly efficient adsorption sites, achieving adsorption capacities of 1.18 mmol g−1 for OBS and 1.02 mmol g−1 for HFPO-TA, with their adsorption equilibrium within 3 h. The adsorption mechanisms were investigated through Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS), and anionic exchange, electrostatic attraction and accumulation on the air bubble surfaces on the adsorbent were proposed. Additionally, the spent CTF2/Fe3O4 was well regenerated by the mixture of NaCl and methanol solution and showed relatively stable adsorption for OBS and HFPO-TA within 5 cycles. This study provides a feasible method to make recyclable COF powders for efficient removal of pollutants from wastewater.

Graphical abstract: Preparation of magnetic covalent triazine frameworks by ball milling for efficient removal of PFOS and PFOA substitutes from water

Supplementary files

Article information

Article type
Paper
Submitted
15 Dis 2021
Accepted
21 Feb 2022
First published
21 Feb 2022

Environ. Sci.: Nano, 2022,9, 1466-1475

Preparation of magnetic covalent triazine frameworks by ball milling for efficient removal of PFOS and PFOA substitutes from water

W. Wang, H. Shao, C. Sun, X. Jiang, S. Zhou, G. Yu and S. Deng, Environ. Sci.: Nano, 2022, 9, 1466 DOI: 10.1039/D1EN01158H

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements