Environmental Science-Nano
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2020
·Vol. 7
·期 8
·2229-2239
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IF 7.683
Xianjun Tan,Guanhan Chen,Dingyu Xing,Wenhui Ding,Hao Liu,Ting Li,Yuxiong Huang
More and more attention has been redirected to per- and polyfluorinated alkyl substances (PFASs), particularly perfluorooctanoic acid (PFOA), owing to their ecotoxicity and environmental risks. As one of the major emerging and persistent contaminants in the environment, the current treatment processes could not remove PFOA efficiently. The recent advances in heterogeneous photocatalysis have demonstrated high efficiencies in degrading persistent contaminants, which provides an alternative approach for PFOA removal. Notably, Ga2O3-based photocatalysts exhibited great potential for PFOA remediation due to their high oxidizing capability and energy sustainability. Thus, Ga2O3 hierarchical nanosheets modified by a series of transition metals were rationally developed, and applied as heterogeneous photocatalysts for fast and efficient PFOA degradation. Noteworthily, the indium modified Ga2O3 hierarchical nanosheets achieved prominent PFOA decomposition activity, which can completely degrade 20 mg L−1 PFOA within 1 hour. The In–Ga2O3 hierarchical composites have dramatically enhanced the degradation kinetics for PFOA, which was 7.8 times higher than that of pristine Ga2O3. With in-depth mechanism investigation, we have demonstrated that In modification can not only enhance light harvesting and suppress photogenerated carrier recombination, but also favor the improvement of the adsorption ability for PFOA through the coexistence of monodentate and bidentate/bridging coordination modes. The transition metals–modification strategy paves the way for fabricating high-performance nanoscale photocatalysts for the removal of PFASs in water.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2024
·
IF 11.4
Jinjing Huang,Kaixing Fu,Zhuoya Fang,Jinming Luo
The effective protocol for treating per- and polyfluoroalkyl substances (PFAS) in water at environmentally relevant concentrations (∼ ng L −1 ) has received unprecedented attention due to the stringent drinking water standards. In order to ensure safe water treatment, sorption using quaternary ammonium functionalized strong-base anion exchange resins (SB-AERs) is considered a viable option for treating PFAS when compared to commercialized activated carbon, as SB-AERs can be in situ regenerated with long-term operation capabilities. However, the harsh conditions required for traditional direct synthesis of SB-AERs (such as prolonged reaction times, complex processes, and environmental pollution caused by the organic reagents used) limit their applications. In this study, we present a novel indirect synthesis method that can effectively pre-functionalizes cellulose for quaternization. This modified cellulose is subsequently loaded onto chloromethylated polystyrene to produce a quaternized cellulose-functionalized polymer resin (QC-CMPS). The process is straightforward to implement, reduces the use of toxic chemicals, and effectively mitigates water safety risks associated with hazardous reagent leaks. As results, the prepared QC-CMPS demonstrates exceptional selective capability for PFAS removal in real environmental water matrices, achieving over 99 % removal efficiency at an initial concentration of 1000 ng L −1 . Additionally, QC-CMPS demonstrates low sensitivity to pH and background ions, effectively removing PFAS from both tap water and lake water with efficiency rates exceeding 95 %. The exhausted QC-CMPS can be readily rejuvenated by rinsing with 1 % NaCl and MeOH (V/V=3/7) mixture, as demonstrated by five successful consecutive cycles. The fixed-bed column test confirmed that ∼ 11,000 bed volumes (∼ 292.70 L) of the feed streams (∼250 ng L −1 ) can be effectively treated with the enrichment factor of 26.42, 25.16, 27.77 and 21.17 for PFOA, PFOS, PFBS, and GenX, respectively, highlighting significant potential for practical applications.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Houlong Yang,Muqiao Han,Wentian Zhang,Ming Yi,Lichao Xia,Fangang Meng,Yan Wang,Shanshan Zhao
Two-dimensional (2D) separation membranes have proved their superiorities in addressing global water scarcity and recycling resources. However, current 2D membranes usually suffer from swelling and irregular stacking issues, which result in poor separation performance. Herein, we developed novel mix-dimensional assembled MXene composite membranes with high permeability and selectivity by intercalating 1D carboxylated cellulose nanofibers (CNFs) into 2D lamellar MXene nanosheets. The effects of chain length of CNFs and MXene/CNFs mass ratios on the morphologies, physicochemical properties, and separation performances of composite membranes were systematically investigated. The optimized MXC-3-L membrane exhibited superior rejection to Congo red (CR, >99%) and remarkable separation efficiency of dye/salt. The separation factors for the CR/NaCl and CR/Na 2 SO 4 mixtures were 512.0 and 517.2, respectively. Moreover, the MXC-3-L membrane showed distinct rejections to perfluoroalkyl substances (PFAS) (>95%) with a nearly 8-fold increase of permeance in comparison with the commercial polyamide membrane. The 2D X-ray diffraction analysis verified that the intercalation of 1D CNFs into 2D MXene nanosheets via strong hydrogen bonding can regulate the nanochannel into more stable and regularly stacking lamellar structures, which plays a key role in high permeance and excellent molecular separation efficiency. In addition, 1D CNFs play an essential role as “threading” and “stitching”, shielding the defects between adjacent MXene nanosheets and improving the separation efficiencies. Our work provides new insights into design of defect-free and highly selective 2D materials-based membranes for enhanced wastewater treatment and molecular sieving.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Cuizhu Sun,Zhenggang Wang,Xinfei Li,Yadan Luo,Hao Zheng,Xuan Li,Lingyun Chen,Fengmin Li
Pollution of water environments by perfluoroalkyl substances (PFASs) has attracted global attention because of their potential risk to the human health. Hence, effective methods for PFAS removal in water environments are urgently needed. Therefore, herein, chitin/polyethylene imine/oxygen-doped graphitic carbon nitride (O-g-C 3 N 4 ) sponges (ChPCNs) are prepared for the efficient removal of two representative PFASs, namely, perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), via an adsorption–photocatalysis “synergistic” mechanism. All ChPCNs exhibit good compressibility and high mechanical strength, and the combination of O-g-C 3 N 4 and chitin enhances the photocatalytic performance of ChPCNs by reducing the bandgap energy, improving the light absorption ability and suppressing the photogenerated electron–hole (h + ) recombination. A ChPCN prepared with an O-g-C 3 N 4 concentration of 200 mg/100 mL (ChPCN-200) efficiently removes 97.9 % and 99.7 % of PFOA and PFOS, respectively, via electrostatic, hydrophobic, and hydrogen bond interactions and hole filling, while ·OH, ·O 2 − , and h + are confirmed to be the active species participating in photodegradation. Notably, the degradation pathway of PFASs involves Kolbe decarboxylation, HF elimination, and oxidation, removing the –CF 2 groups in a step-by-step manner, resulting in gradual degradation into short-chain PFASs and releasing F − . Importantly, the removal efficiency for PFASs by ChPCNs reaches 93.7 % in simulated reclaimed water, with the sponges exhibiting good reusability. This study successfully develops reusable chitin-based materials for efficient removal of PFASs from reclaimed water, providing a promising method for the control of emerging pollutants in water environments.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）