Rapid degradation of PFOA by the activated peroxymono-sulfate with FeCo/MoS2 catalyst. Issue 2 (April 2023)

• Record Type: Journal Article
• Authors: Lv, Yuancai; He, Shiyu; Liu, Shuting; Yu, Zhendong; Jiang, Yanting; Hu, Yihui; Liu, Yifan; Lin, Chunxiang; Ye, Xiaoxia; Yang, Guifang; Liu, Minghua
• Is Part Of: Journal of environmental chemical engineering. Volume 11:Issue 2(2023)
• Publication Date: 2023-04
• Subjects: Persulfate activation -- Perfluorooctanoic acid (PFOA) -- Ecotoxicity; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2023.109467
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: Doping polymetals on Fe-based catalysts is proved to be an effective way to improve the performance on activating persulfate. In this paper, a highly efficient persulfate activation catalyst (FeCo@MoS2 ) was successfully synthesized by introducing MoS2 onto the surface of FeCo nanoboxes. During the activation of PMS the introduced of MoS2 effectively promoted the formation of free radicals (∙OH, SO4 · - ), 1 O2 and Fe(IV). Due to the synergistic effects between Mo and Fe, FeCo@MoS2 has better catalytic activity (2.01 times larger of defluorination efficiency and 3.91 times larger of the apparent rate constant ( k obs )) than FeCo. Under the optimal conditions (catalyst dosage of 0.2 g L −1, PMS dosage of 1.0 g L −1 and initial pH 4.0), the perfluorooctanoic acid (PFOA, 10 mg L −1 ) could be degraded in 60 min, with 90.26 ± 2.64% of the defluorination efficiency. The LC- MS results showed that under the attack of free radicals (∙OH, SO4 · - ), 1 O2 and Fe(IV), the PFOA underwent step-by-step defluorination process. In addition, the ECOSAR results showed that during the whole degradation of PFOA in FeCo@MoS2 /PMS system, no highly toxic intermediates was accumulated, suggesting a green degradation process. This work showed new ideas and strategies for studying the influence of polymetallic doping on the catalytic process of PMS multiphase catalytic system. Highlights: Structure and chemical composition of FeCo@MoS2 were studied. Performance on PMS activation for PFOA was evaluated. Role of MoS2 in promoting PMS activation was also explored. Pathway and mechanism for PFOA degradation were proposed. Toxicity of the intermediates during PFOA degradation were evaluated.