Plasma Research Laboratory, Department of Chemical and Biomolecular Engineering, Clarkson University, Potsdam, New York 13699, United States.
Emerging Compounds Treatment Technologies (ECT2) Inc., Portland, Maine 04103, United States.
Environ Sci Technol. 2020 Nov 3;54(21):13973-13980. doi: 10.1021/acs.est.0c02158. Epub 2020 Oct 25.
"High-concentration" and "low-concentration" bench-scale batch plasma reactors were used to effectively degrade per- and polyfluoroalkyl substances (PFAS) at a high concentration (∼100 mg/L) and a low concentration (<1 μg/L), respectively, in ion exchange (IX) regenerant still bottom (SB) solutions. In the SBs, numerous PFAS were detected with a wide concentration range (∼0.01 to 100 mg/L; total oxidizable precursors (TOP) ∼4000 to 10000 mg/L). In the "high-concentration" plasma reactor, the concentrations of PFAS precursors and long-chain perfluoroalkyl acids (PFAAs) (≥6C for PFSAs and ≥8C for perfluorocarboxylic acids (PFCAs)) were decreased by >99.9% in 2 h, and short-chain PFAAs (<6C for perfluorocarboxylic acids (PFSAs) and <8C PFCAs) were decreased by >99% in 6 h of treatment. Subsequently, a "low concentration" plasma reactor was used to remove additional PFAAs. In this reactor, the addition of CTAB (cetrimonium bromide, a cationic surfactant) caused short-chain PFAAs, other than PFBA, to be removed to below detection limits in 90 min of treatment time. Overall, >99% of the TOP present in SBs was removed during the treatment. Fluorine recovery of 47 to 117% was obtained in six SB samples. Energy requirement (EE/O) for the treatment of PFOA and PFOS from SBs ranged from 380 to 830 kWh/m.
"高浓度"和"低浓度"台式批量等离子体反应器分别用于有效降解高浓度（100mg/L）和低浓度（<1μg/L）的全氟和多氟烷基物质（PFAS）。在交换（IX）再生器底部（SB）溶液中，存在许多 PFAS，浓度范围很宽（0.01 至 100mg/L；总可氧化前体（TOP）~4000 至 10000mg/L）。在"高浓度"等离子体反应器中，PFAS 前体和长链全氟烷基酸（PFAAs）（PFSAs 中≥6C 和 PFCAs 中≥8C）的浓度在 2 小时内下降了>99.9%，而短链 PFAAs（PFSAs 中<6C 和 PFCAs 中<8C）在 6 小时的处理中下降了>99%。随后，使用"低浓度"等离子体反应器去除额外的 PFAAs。在该反应器中，添加 CTAB（十六烷基三甲基溴化铵，一种阳离子表面活性剂）可使除 PFBA 以外的短链 PFAAs在 90 分钟的处理时间内降至检测限以下。总的来说，在处理过程中，SB 中存在的 TOP 有>99%被去除。从六个 SB 样品中回收氟的比例为 47%至 117%。从 SB 中处理 PFOA 和 PFOS 的能源需求（EE/O）范围为 380 至 830kWh/m。
