Role of the air-water interface in removing perfluoroalkyl acids from drinking water by activated carbon treatment
Role of the air-water interface in removing perfluoroalkyl acids from drinking water by activated carbon treatment
复制标题
空气-水界面在活性炭处理去除饮用水中全氟烷基酸中的作用
DOI：
10.1016/j.jhazmat.2019.121981
复制
发表时间：
2020-03-15
影响因子：
13.6
通讯作者：
Deng, Shubo
中科院分区：
文献类型：
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作者：
Meng, Pingping;Jiang, Xiangzhe;Deng, Shubo
全氟烷基和多氟烷基物质（PFASs）对饮用水的污染是一个世界性的问题。本研究首次揭示了气-水界面在强化两种活性炭（AC）曝气吸附去除长链全氟烷基羧酸（PFCAs; CnF 2n +1COOH，n ≥ 7）和全氟烷基磺酸（PFSAs; CnF 2n +1 SO 3 H，n ≥ 6）（统称为全氟烷基酸（PFAAs））中的作用。曝气被证明，以提高去除长链PFAA通过吸附在空气-水界面和随后的吸附PFAA富集的空气气泡的AC。选定的长链全氟辛酸的去除率增加了50- 115%的辅助曝气，这取决于全氟烷基链的长度。曝气是更有效地提高长链PFAA去除空气-水界面吸附增加PFAA链长，由于更高的表面活性。在通过离心去除吸附的气泡后，高达80%的长链PFAA能够从吸附剂解吸，证实了空气-水界面对PFAA在AC上的吸附的贡献。活性炭处理水过程中的曝气可以促进长链全氟乙酸的去除，改善活性炭的处理性能。
Contamination of drinking water by per- and polyfluoroalkyl substances (PFASs) is a worldwide problem. In this study, we for the first time revealed the role of the air-water interface in enhancing the removal of long-chain perfluoroalkyl carboxylic (PFCAs; CnF2n+1COOH, n >= 7) and perfluoroalkane sulfonic (PFSAs; CnF2n+1SO3H, n >= 6) acids, collectively termed as perfluoroalkyl acids (PFAAs), through combined aeration and adsorption on two kinds of activated carbon (AC). Aeration was shown to enhance the removal of long-chain PFAAs through adsorption at the air-water interface and subsequent adsorption of PFAA-enriched air bubbles to the AC. The removal of selected long-chain PFAAs was increased by 50-115 % with the assistance of aeration, depending on the perfluoroalkyl chain length. Aeration is more effective in enhancing long-chain PFAA removal as air-water interface adsorption increases with PFAA chain length due to higher surface activity. After removing adsorbed air bubbles by centrifugation, up to 80 % of the long-chain PFAAs were able to desorb from the sorbent, confirming the contribution of the air-water interface to the adsorption of PFAAs on AC. Aeration during AC treatment of water could enhance the removal of long-chain PFAAs, and improve the performance of AC during water treatment.