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[Display omitted] • A novel CoFe 2 O 4 -THFM was prepared via electro-deposition and followed by calcination. • The Fe(II) reinforced the valance transformation of Co(III) to Co(II). • The Co/Fe synergism played a key role in the non-radical-dominated oxidation mechanism. • The CoFe 2 O 4 -THFM MFPA process showed wide-pH adaptation and stability for water treatment. Constructing membrane filtration coupled with peroxymonosulfate (PMS) activation system has emerged as a promising strategy for efficient water purification. In this work, a novel CoFe 2 O 4 -titanium hollow fiber membrane (CoFe 2 O 4 -THFM) filtration system was proposed, aiming to integrate Co/Fe synergism and membrane filtration for enhancing PMS activation (MFPA) toward phenol (PE) removal. The performance of CoFe 2 O 4 -THFM MFPA process was rationally regulated via electro-deposition and calcination process, which displayed 100 % PE removal and showed 4.80 and 1.24 times (under 2 min running time) higher than that of FeO-THFM and CoO-THFM MFPA process. Mechanism analysis revealed a non-radical-dominated oxidation mechanism (involving 1O 2 , Fe(VI)=O and electron transfer), primarily attributed to the crucial role of Fe. On the one hand, the synergistic promotion mechanism of dual metal centers (Co(III)/Fe(II)) in the PMS activation process significantly enhanced the content of Co(II), and together with Fe(II) acted as active sites to generate reactive oxygen species (ROS, especially 1O 2) for PE removal. On the other hand, the generated Fe(VI)=O (from Fe(III)) tend to react with PE (electron-donating), while the formed CoFe 2 O 4 -THFM-PMS* complex (oxygen vacancy (O V) mediated) plundered electrons from PE (electron transfer), leading to its oxidation. The notable non-radical process (1O 2 , Fe(VI)=O and electron transfer) mentioned above contributed to the excellent performance in real water matrix. [ABSTRACT FROM AUTHOR]

Catalytic membrane process, which combines membrane filtration and advanced oxidation, has promising application prospects in water decontamination. In this work, a novel metal-free coal-based catalytic carbon membrane (PPy/CCM-800) was developed and applied for the typical EDC-bisphenol A (BPA) removal from water via activating peroxymonosulfate (PMS). Morphology investigation manifested that the N-doped carbon nanospheres derived from the pyrolytic PPy particles distributed evenly on the surface of coal-based carbon membrane (CCM). In contrast to bare CCM, catalytic performance of PPy/CCM-800 was significantly enhanced by the anchoring of N-doped carbon nanospheres, and 97.89 % of BPA and 60.83 % of total organic carbon (TOC) can be removed by PPy/CCM-800 during catalytic filtration treatment. Catalytic mechanism investigations confirmed that the excellent decontamination performance of PPy/CCM-800 was attributed to the synergistic effects of radical and non-radical oxidation pathway, and the non-radical pathway (1O 2 and direct electron transfer) played the dominant role. Moreover, the possible BPA degradation pathways were proposed based on the density functional theory (DFT) calculations and HPLC-MS results. [Display omitted] • N-doped carbon nanospheres functionalized coal-based catalytic carbon membrane was developed. • The deposition of N-doped carbon nanospheres significantly improve the catalytic performance of CCM. • Non-radical mechanism played the dominant role in BPA removal during the treatment. • PPy/CCM-800 exhibits excellent applicability for BPA removal in different water matrixes. [ABSTRACT FROM AUTHOR]

Co-based peroxymonosulfate (PMS) activation system with fascinating catalytic performance has become a promising technology for water purification, but it always suffers from insufficient mass transfer, less exposed active sites and toxic metal leaching. In this work, a carbon nanotube membrane confining Co 3 O 4 inside (Co 3 O 4 -in-CNT) was prepared and was coupled with PMS activation (catalytic membrane process) for sulfamethoxazole (SMX) removal. Compared with counterpart with surface-loaded Co 3 O 4 (Co 3 O 4 -out-CNT), the Co 3 O 4 -in-CNT catalytic membrane process exhibited enhanced SMX removal (99.5% vs. 89.1%) within residence time of 2.89 s, reduced Co leaching (20 vs. 147 μg L−1) and more interestingly, the nonradical-to-radical mechanism transformation (from 1O 2 and electron transfer to SO 4 •− and •OH). These phenomena were ascribed to the nanoconfinement effect in CNT, which enhanced mass transfer (2.80 × 10−4 vs. 5.98 × 10−5 m s−1), accelerated Co3+/Co2+ cycling (73.4% vs. 65.0%) and showed higher adsorption energy for PMS (cleavage of O–O bond). Finally, based on the generated abundant reactive oxygen species (ROS), the seven degradation pathways of SMX were formed in system. [Display omitted] • A novel flow-through confined cobalt-based PMS activation system was constructed. • The Co 3 O 4 -in-CNT catalytic membrane process showed a superfast SMX removal. • Nonradical-to-radical-dominated mechanism was regulated via nanoconfinement effect. • The redox potential played a key role in high selectivity for SMX removal. • The degradation pathways of SMX were deduced by theoretical calculations and HPLC-MS. [ABSTRACT FROM AUTHOR]

• A novel confined Fe-based PMS catalytic membrane system was established. • The Fe 2 O 3 @OCNT MFPA process showed an efficient TC removal. • This system showed good anti-interference for real water treatment. • The non-radical electron transfer was enhanced via the nanoconfinement effect. • The degradation pathway of TC was proposed via LC-MS and theoretical calculations. The water treatment performance of metal-based peroxymonosulfate (PMS) catalytic membrane is always limited by the finite residence time and complex water matrixes. Therefore, the development of high efficiency and anti-interference PMS catalytic membrane is of great significance. In this work, an oxidized carbon nanotube membrane with Fe 2 O 3 nanoparticle confined inside (Fe 2 O 3 @OCNT) has been fabricated for enhanced PMS activation in the membrane filtration process (MFPA process). The experiment results showed that through fine-tuning the confinement degree of Fe 2 O 3 in OCNT, the non-radical electron transfer pathway was gradually enhanced and became the dominant process. Under the suitable confinement condition, the tetracycline (TC) removal in the Fe 2 O 3 @OCNT MFPA process was up to 96.1 % with a residence time of only 8.0 s, which remarkably outperformed the powder-based or batch process. The high efficiency of the membrane was attributed to the enhanced mass transfer and non-radical electron transfer process due to the nanoconfinement effect. This was supported by theoretical calculations, where it was showed that confining Fe 2 O 3 inside OCNT not only enhanced the electron activity in the lumen of OCNT, but also increased the adsorption energy for PMS. In addition, the four possible degradation pathways of TC were proposed based on Fukui function analysis and LC-MS results. This system displayed reusability and good stability for TC removal (5 cycles > 85 %, low Fe leaching of 10 μg·L-1, and long-term running of 48 h) and wide applicability for different pollutants, while also demonstrated unique anti-interference property in the presence of inorganic ions and in real water matrixes. [ABSTRACT FROM AUTHOR]

Developing high-efficient and stable catalytic membrane is of great significance for the removal of organic pollution from water. In this work, novel ZIF-67-derivative- functionalized Ti-based catalytic membranes (ZTM-T) with peroxymonosulfate (PMS) activation and membrane filtration dual-function was first designed and fabricated via a facile electro-deposition method combined with low temperature calcination. Changing deposition and calcination conditions could effectively tune the structure and thus catalytic performance of ZTM-T. Under optimal conditions, the as prepared ZTM-450 catalytic membrane exhibited superior sulfamethoxazole (SMX) removal efficiency of up to 96.3%, which was 216.7 and 3.8 times higher than that of membrane filtration alone and PMS alone, respectively. Meanwhile, ZTM-450 catalytic membrane also showed high treatment performance for real water matrix and long-term operation. The efficient SMX removal by ZTM-450 catalytic membrane was attributed to the combination of radical (SO 4 •− and •OH) and non-radical (1O 2 and electron transfer) oxidation pathways, and 1O 2 played the dominant role. In addition, it was found that the ZTM-450 catalytic membrane showed unique selectivity for SMX removal among six different antibiotics. Mechanism study demonstrated that this was mainly due to the preferential removal of negatively charged antibiotic pollutants based on electrostatic repulsion and electrophilic attack of 1O 2 , and SMX has the strongest hydrophobicity and the lowest redox potential among these antibiotic pollutants. Furthermore, a possible mechanism for the degradation of SMX was explored via density functional theory (DFT) analysis and HPLC-MS. [Display omitted] • A novel strategy was proposed to construct a MOF-based PMS-catalytic Ti membrane. • The efficient removal of ZTM-450 for SMX was due to radical and non-radical process. • The ZTM-450 showed a unique selectivity for SMX removal. • The degradation mechanism of SMX was illustrated via HPLC-MS and DFT analysis. [ABSTRACT FROM AUTHOR]