Environments
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2024
·Vol. 11
·期 7
·136
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IF 3.5
Junhao Zheng,Mei Jiang,Qingzhu Li,Weichun Yang
Fe/Mn (hydr)oxides are metallic compounds that exhibit significant redox activity in environmental media and play a pivotal role in geochemical processes, thereby influencing the fate of metals in porous media. The morphology of Fe/Mn (hydr)oxides in natural environments and their interactions with trace metals are significantly influenced by the presence of natural organic matter (NOM). However, there is limited understanding regarding the formation, transport, and stability of Fe/Mn (hydr)oxides in the environment. The present study employed humic acid (HA) as a representative NOM material to investigate the positive influence of HA on the formation of Fe/Mn colloids. However, there remains limited comprehension regarding the formation, transport, and stability of Fe/Mn (hydr)oxides in the natural environment. In this study, we investigated the positive effect of natural organic matter (NOM) on the formation of Fe/Mn colloids using humic acid (HA) as a representative NOM material. We comprehensively characterized the chemical and physical properties of HA–Fe/Mn colloids formed under various environmentally relevant conditions and quantitatively analyzed their subsequent aggregation and stability behaviors. The findings suggest that the molar ratios of C to Fe/Mn (hydr)oxide play a pivotal role in influencing the properties of HA–Fe/Mn colloids. The formation and stability of HA–Fe/Mn colloids exhibit an upward trend with increasing initial molar ratios of C to Fe/Mn. Redox and metal–carboxylic acid complexation reactions between HA and hydrated iron/manganese oxides play a pivotal role in forming colloidal HA–Fe/Mn complexes. Subsequent investigations simulating porous media environments have demonstrated that the colloidal structure resulting from the interaction between HA and Fe/Mn facilitates their migration within surrounding porous media while also enhancing their retention in the surface layers of these media. This study offers novel insights into the formation and stabilization mechanisms of HA–Fe/Mn colloids, which are pivotal for comprehending the behavior of Fe/Mn colloids and the involvement of Fe/Mn (hydr)oxides in geochemical cycling processes within porous media.
研究领域:
环境科学
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地球化学
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胶体化学
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DOI
高影响因子
ENVIRONMENT INTERNATIONAL
·
2025
·
IF 9.7
Jiaqi Shi,Yan Li,Qi Wei,Xin Zhu,Shaohua Cao,Wenyi Xie,Yang Guo,Jing Wei,Zekai Li,Tao Long
The widely used rubber antioxidant N-(1,3-Dimethylbutyl)-N’-phenyl-p-phenylenediamine (6PPD) and its ozonated product, 6PPD-quinone (6PPD-Q), are highly toxic to aquatic life, yet understanding on their environmental behaviors is limited. This study comprehensively investigated their adsorption and transformation processes on natural Fe-Mn nodules (NFMN), which commonly exist in sediments and soils through a combination of diverse experimental and computational methods. The maximum adsorption capacity of 6PPD-Q (719.2 μg·g −1 ) is significantly higher than that of 6PPD (133.8 μg·g −1 ) at 293 K, and it is more difficult to desorb. They follow different kinetic and isothermal adsorption models, and environmental conditions (including temperature, pH, and anions) exert distinct influences on the adsorption of the two substances. Adsorption mechanisms involving electrostatic attraction, charge transfer, hydrogen bonding, and Lewis acid-base complexation were unveiled. For 6PPD, electrostatic adsorption and Lewis acid-base complexation contribute significantly to its adsorption. Conversely, for 6PPD-Q, the contribution of Lewis acid-base complexation outweighs that of hydrogen bonding, while the effect of electrostatic adsorption is relatively negligible. The stronger electrostatic attraction, more efficient charge transfer, and a greater number of binding sites for hydrogen bonding and Lewis acid-base complexation with NFMN results in more robust adsorption of 6PPD-Q. Furthermore, 6PPD can transform into 6PPD-Q on NFMN, facilitated by dissolved Mn(III). This study advances understanding of the adsorption behavior and mechanism of 6PPD and 6PPD-Q, and highlights a new pathway for 6PPD-Q formation, which provides valuable reference for assessing the water body exposure risks and formulating environmental remediation strategies for such pollutants. Environmental Implication This study offers the first comprehensive insight into the interactions between 6PPD/6PPD-Q and NFMN, illuminating their environmental behavior in water and soil systems. It reveals the adsorption discrepancy between 6PPD and 6PPD-Q, and elucidates the mechanisms underlying the difference in adsorption. Additionally, it uncovers a novel pathway for 6PPD-Q formation, offering valuable implications for risk assessment and environmental remediation strategies.
研究领域:
环境科学
·
化学
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DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2020
·
IF 3.99
Jiahui Deng,Yalin Cheng,Min Liu,Biyang Tu,Shan Xue,Haisheng Tao
In this study, Fe-Mn co-embed sodium alginate carbon spheres (Fe-Mn/SA-C) were prepared as a cost-effective adsorbent for aqueous Cd(II) removal by a facile pyrolysis method. The morphology and chemical composition of Fe-Mn/SA-C were explored with various characterized techniques. The results indicate that Fe-Mn/SA-C possess porous structures and abundant oxide-based functional groups. Fe-Mn/SA-C exhibits excellent adsorption properties for aqueous Cd(II) and the adsorption process is pH-dependent. The adsorption data could fit pseudo second-order and Langmuir models well, suggesting that chemisorption is a dominant adsorption mechanism and the maximum adsorption capacity is 280.11 mg −1 . Thermodynamic analysis demonstrates that the adsorption is spontaneous and endothermic. The adsorption mechanisms of Cd(II) include the complexation of Cd(II) with oxygen-based functional groups, precipitation, and ion exchange. Finally, the granulated and magnetic Fe-Mn/SA-C is an efficient and practical adsorbent for cadmium-containing wastewater treatment.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Journal of Materials Chemistry A
·
2019
·Vol. 7
·期 6
·2845-2854
·
IF 10.733
Tianshu Zhang,Jing Wang,Wentao Zhang,Chengyuan Yang,Liang Zhang,Wenxin Zhu,Jing Sun,Guoliang Li,Tao Li,Jianlong Wang
Highly efficient decontamination of naturally occurring As(III) from aqueous media remains a rigorous task for public health and ecosystem protection. As its increasingly acute toxicity and mobile characteristics than those of As(V), it is imperative to exploit a technique for the simultaneous removal and detoxication of As(III). Herein, a novel strategy involving outer and inner structural engineering of an amorphous FeMn-MOF-74 adsorbent was developed via a facile temperature-controlled crystallization method, which integrated the inner amorphous structure with low-coordinated active centers and the outer optimized metal atomic ratio with homogeneous adsorption/oxidation sites for generating the synergistic effects of As(III) removal. An appropriate Fe/Mn ratio (∼1.96) with optimized temperature (denoted as aFMM-120) endows the synergic effect of iron and high-valence manganese nodes in the framework with the highest experimental adsorption capacity of 161.6 mg g−1 among MOF-based arsenic adsorbents. Detailed characterizations through X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy demonstrated the redox behavior of Mn species and surface coordination of oxygen molecules in FeO clusters toward As(III). All these results imply that amorphous aFMM-120 is an effective adsorptive oxidation material for efficient arsenic-contaminated water remediation.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2024
·Vol. 18
·期 11
·1-10
·
IF 4.3
Liang Haoting,Zhao Qiao,Liu Shengkun,Wei Chongyang,Wang Yidan,Wang Yue,Huang Shouying,Ma Xinbin
The Fe-Mn bimetallic catalyst is a potential candidate for the conversion of CO 2 into value-added chemicals. The interaction between the two metals plays a significant role in determining the catalytic performance, however which remains controversial. In this study, we aim to investigate the impact of tuning the proximity of Fe-Mn bimetallic catalysts with similar nanoparticle size. And its effect on the physicochemical properties of the catalysts and corresponding performance were investigated. It was found that closer Fe-Mn proximity resulted in enhanced CO 2 hydrogenation activity and inhibited CH 4 formation. The physiochemical properties of prepared catalysts were characterized using X-ray diffraction, H 2 temperature programmed reduction, and X-ray photoelectron spectroscopy, revealing that a closer Fe-Mn distance promoted electron transfer from Mn to Fe, thereby facilitating Fe carburization. The adsorption behavior of CO 2 and the identification of reaction intermediates were analyzed using CO 2 -temperature programed desorption and in situ Fourier transform infrared spectroscopy, confirming the intimate Fe-Mn sites contributed to CO 2 adsorption and the formation of HCOO* species, ultimately leading to increased CO 2 conversion and hydrocarbon production. The discovery of a synergistic effect at the intimate Fe-Mn sites in this study provides valuable insights into the relationship between active sites and promoters.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
WATER ENVIRONMENT RESEARCH
·
2022
·Vol. 94
·期 4
·e10714
·
IF 3.306
Yao Shi,Yifei Xing,Zhilian Song,Xueming Dang,Huimin Zhao
Fe–Mn binary oxide (FMBO) is a promising adsorbent for As(III) removal through combined adsorption and oxidation. The calcined oyster shell-supported Fe–Mn binary oxide (FMBO/OS) adsorbent was synthesized by the co-precipitation method. Results indicated that the calcined oyster shell, as a carrier, improved the stability of FMBO and its adsorption capacity for As(III). The maximum adsorption capacity of FMBO/OS on As(III) reached 140.5 mg·g −1 . Under pH 5.0 and 25°C, the removal efficiency of FMBO/OS to As(III) solution (C 0 = 10 mg·L −1 ) reached 87% within 12 h. Moreover, based on the characterization analyses, the removal mechanisms of As(III) were deduced to include the combined adsorption and oxidation process of FMBO and the synergistic effect of oyster shells. This work provides new insights into synthesizing efficient and green adsorbents to remove aqueous As(III). Meanwhile, it provides technical support for reusing waste biomass materials such as the oyster shell. Practitioner Points FMBO/OS was prepared by a simple hydrothermal co-precipitation method. The carrier alleviates the agglomeration of Fe–Mn oxides. The adsorbent shows a strong adsorption capacity of As(III) and good selectivity. The good results benefit from the synergistic effect of calcium arsenate generation. The prepared adsorbent can adsorb arsenic in real samples.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2021
·
IF 19.503
Zhe Chen,Xiaobin Liao,Congli Sun,Kangning Zhao,Daixin Ye,Jiantao Li,Gang Wu,Jianhui Fang,Hongbin Zhao,Jiujun Zhang
Constructing and excavating single atom catalysts with high-density active sites and long-life durability for energy storage and conversion devices still remain bestially challenges. In this paper, a novel dual-site electrocatalyst with atomically dispersed Fe/Mn-N x -C dual metal sites embedded in N-doped carbon matrix is successfully designed and synthesized, which exhibits a state-of-the-art oxygen reduction reaction (ORR) activity with a half-wave potential (E 1/2 ) of 0.88 V (vs. RHE) as well as a superior stability. Besides, the Fe/Mn-N x -C catalyst reaches a high power density of 208.6 mW cm −2 and a specific energy density of 825.5 W h kg -1 when this catalyst is employed in Zn-air battery, which is superior to most of the reported non-precious catalysts. Furthermore, theoretical DFT calculations reveal the excellent performance is induced through a synergic dual-site cascade mechanism, which overcomes the issue of low adsorption energy (E ads ) of *OH on Fe-N x site, followed by transfer of the *OH to adjacent Mn-N x sites. As a result, the first three steps during ORR more favored occur on the Fe-N x sites instead of the Mn sites to generate *OOH and *O intermediates due to the lower energy barriers. This mechanism is further approved by addition of methanol to verify the preferred adsorption of *OH on the Mn-N x site.
研究领域:
材料科学
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催化化学
·
能源存储与转换
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
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2024
·
IF 4
Yue Yin,Yanming Xu,Ya-Nan Luan,Zhuo Zhao,Yihua Xiao,Changqing Liu
A novel porous Fe-Mn chitosan bead (PFMB) was fabricated through the freeze-drying technique for the enhanced oxidation and adsorption of arsenite (As(Ⅲ)) from aqueous solution. The porous internal structure of PFMB provided a significantly higher As(Ⅲ) oxidation and adsorption rate than solid Fe-Mn chitosan bead (FMB). The experimental results showed that FMB and PFMB exhibited the theoretical maximum As(Ⅲ) adsorption capacities of 27.42 and 49.80 mg/g, respectively. The real-time oxidation and adsorption progress of As(Ⅲ) onto PFMB was deeply evaluated: PFMB effectively oxidized As(Ⅲ) to As(Ⅴ) and the generated As(Ⅴ) was subsequently adsorbed. The operational parameters (initial pH, adsorbent dosage, ionic strength, and HA concentration) were thoroughly investigated and had no significant influence on As(Ⅲ) removal by PFMB. Finally, the regeneration experiment showed that PFMB can be easily regenerated and the recycled PFMB can successfully remove As(Ⅲ) in the following 5 cycles. Column experiments suggested that the column device could effectively remove the As(Ⅲ) in more than 3830 bed volume with the influent velocity at 0.5 mL/min before effluent concentration reached 0.05 mg/L. These results revealed the enhanced oxidation and adsorption performance of As(Ⅲ) onto PFMB and provided a reference for the future application of PFMB in arsenic-contaminated water treatment.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Surfaces and Interfaces
·
2025
·
IF 6.3
Jiangang Kang,Haihong Zhang,Yuehui He,Liang Wu,Hengdi Ye,Jinchao Wei
The novel Ni-Si intermetallic compounds are fabricated by elemental powder metallurgy. This study explores the synthesis of a series of catalysts (Ni-Si-M, M=Co, Fe, Mn) by alloying to augment the low-temperature efficiency of CO oxidation using Ni-Si intermetallic compounds. It is found the low-temperature catalytic activity of Ni-Si-Co, Ni-Si-Fe, and Ni-Si-Mn catalysts are significantly enhanced compared to the original Ni-Si. The catalytic activity among the catalysts ranks as follows: Ni-Si-Co > Ni-Si-Fe > Ni-Si-Mn > Ni-Si. The apparent activation energy (Ea) for Ni-Si-Co was the lowest at 57.3 kJ/mol, suggesting its efficient catalytic oxidation of CO. Additionally, the addition of Co, Fe and Mn elements actually promotes the generation of Ni 2+ as the CO adsorption site in the original Ni-Si. The addition of Co element also leads to the formation of Co 2+ as the adsorption site of O 2 in the process of CO oxidation reaction. The synergistic adsorption of Ni 2+ and Co 2+ to CO and O 2 promotes the CO oxidation reaction. Additionally, the catalysts demonstrate robust long-term stability in atmospheres containing H 2 O and SO 2 , with CO conversion initially suppressed but subsequently recovering and stabilizing at over 90%. This investigation offers novel insights into enhancing the low-temperature activity and stability of catalysts.
研究领域:
材料科学
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催化化学
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产品关联
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2021
·
IF 4.952
Yaru Han,Linpin Luo,Liang Zhang,Yi Kang,Hao Sun,Jie Dan,Jing Sun,Wentao Zhang,Tianli Yue,Jianlong Wang
Nanozymes have become a frontier of research recently and possess broad application prospects in the field of analytical sensing. Herein, a Fe–Mn bimetallic nanozyme (FeMnzyme) was proposed for colorimetric analysis of ascorbic acid (AA). The FeMnzyme, with high specific surface area, consisted of Fe–Mn mixed oxide amorphous core and α-FeOOH nanorod shell characterized by scanning electron microscope (SEM) and Powder X-ray diffraction (XRD). It exhibits typical oxidase-like properties to catalyze oxidation of colorless 3,3′,5,5′-tetramethylbenzidine (TMB) to generate visible blue oxidized TMB (oxTMB) without exogenous H 2 O 2 . Due to the reducibility of AA to oxTMB, the FeMnzyme/oxTMB system can be employed as a promising colorimetric sensor for quantitative analysis of AA. The method has a good linear concentration range of 8 μmol L −1 to 56 μmol L −1 , and the detection limit is as low as 0.88 μmol L −1 (3σ). Finally, the proposed biosensor has been favorably put into use to determine AA content in kiwi fruit, indicating its reliability for practical application.
研究领域:
分析化学
·
生物传感
·
食品科学
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产品关联
DOI
高影响因子
CHEMOSPHERE
·
2023
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IF 8.8
Qiong Wu,Chunying Dong,Maoxiang Chen,Yu Zhang,Meiqiang Cai,Yan Chen,Micong Jin,Zongsu Wei
In this study, SiO 2 -composited biochar decorated with Fe/Mn was prepared by co-pyrolysis method. The degradation performance of the catalyst was evaluated by activating persulfate (PS) to degrade tetracycline (TC). The effects of pH, initial TC concentration, PS concentration, catalyst dosage and coexisting anions on degradation efficiency and kinetics of TC were investigated. Under optimal conditions (TC = 40 mg L −1 , pH = 6.2, PS = 3.0 mM, catalyst = 0.1 g L −1 ), the kinetic reaction rate constant could reach 0.0264 min −1 in Fe 2 Mn 1 @BC-0.3SiO 2 /PS system, which was 12 times higher than that in the BC/PS system (0.00201 min −1 ). The electrochemical, X-ray diffractometer (XRD), Fourier transform infrared spectrum (FT-IR) and X-ray photoelectron spectroscopy (XPS) analysis showed that both metal oxides and oxygen-containing functional groups provide more active sites to activate PS. The redox cycle between Fe(II)/Fe(III) and Mn(II)/Mn(III)/Mn(IV) accelerated the electron transfer and sustained the catalytic activation of PS. Radical quenching experiments and electron spin resonance (ESR) measurements confirmed that surface sulfate radical (SO 4 •− ) play a key role in TC degradation . Three possible degradation pathways of TC were proposed based on high-performance liquid chromatography coupled with high-resolution mass spectrometry (HPLC-HRMS) analysis, the toxicity of TC and its intermediates was analyzed by bioluminescence inhibition test. In addition to the enhanced catalytic performance, the presence of silica also improved the stability of the catalyst, as confirmed by cyclic experiment and metal ion leaching analysis. The Fe 2 Mn 1 @BC-0.3SiO 2 catalyst, derived from low-cost metals and bio-waste materials, offer an environmentally friendly option to design and implement heterogenous catalyst system for pollutant removal in water.
研究领域:
环境科学
·
污染治理
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材料科学
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2019
·Vol. 26
·期 14
·14350-14361
·
IF 2.914
Wu Kang,Si Xiongyuan,Jiang Jin,Si Youbin,Sun Kai,Yousaf Amina
In this study, a novel Fe–Mn binary oxide (FMBO), which combined the oxidation capability of iron and manganese oxides, was constructed to remove sulfamethoxazole (SMX) effectively using the simultaneous co-precipitation and oxidation methods, and the reaction products were probed by liquid chromatography-mass spectrometry (LC/MS). Particularly, FMBO-mediated transformation mechanisms of SMX were explored using radical scavengers and electron paramagnetic resonance (EPR). Results indicated that the best removal efficiency was obtained at a pH of 4.0, with the H 2 O 2 of 6.0 mmol/L and the FMBO dosage of 2.0 g/L, giving 97.6% removal of 10 mg/L SMX within 60 min. More importantly, we found that the hydroxyl (•OH) radicals generated by FMBO through Fenton-like reaction were responsible for the SMX oxidation. EPR studies were confirmed that the peak intensities of hydroxyl adduct decreased remarkably with increasing pH values. Moreover, the four SMX degradation intermediate products were detected by LC/MS and a reaction pathway for the possible mineralization of SMX, with •OH radicals as the main oxidant, was proposed. These findings provide a novel insight into the removal of SMX by FMBO-mediated radical reactions in aquatic environments. Moreover, this research suggested that FMBO can act as an efficient catalyst to remove SMX in hospital wastewater.
研究领域:
环境科学
·
化学工程
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）