CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Yunjin Yao,Wei Wang,Hongwei Hu,Lijie Zhang,Ziwei Ma,Shaobin Wang
Nickel–manganese bimetallic sulfide microparticles in situ grown on Ni foam (NiMnS@NF) with controllable morphology and composition were developed via a hydrothermal method to boost potassium periodate activation for oxidation of multiple micropollutants. Benefiting from the unique morphology and structure, along with a synergistic effect of different components, the optimized NiMnS@NF exhibits outstanding performance and durability in potassium periodate activation, surpassing other oxidant systems (e.g., H 2 O 2 , peroxydisulfate, and peroxymonosulfate). Electron spin resonance analysis, scavenging tests, electrochemical analysis, and galvanic oxidation tests unveiled that NiMnS@NF can initiate the activation of potassium periodate, resulting in the formation of high-potential metastable intermediates (NiMnS@NF–potassium periodate*). Additionally, superoxide radical anions play a cooperative role in organic elimination. The experimental results further indicate that the synergy among Mn/Ni and S induces a local charge redistribution, improving electron transfer capability and Mn(II)/Mn(III)/Mn(IV) and Ni(II)/Ni(III) redox reactions. This work proposes a feasible and efficient monolithic catalyst for environmental 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
WATER RESEARCH
·
2021
·
IF 11.236
Yuan Gao,Yang Zhou,Su-Yan Pang,Jin Jiang,Yong-Ming Shen,Yang Song,Jie-Bin Duan,Qin Guo
In recent years, the activation of persulfates (peroxydisulfate (PDS) and peroxymonosulfate (PMS)) via transition metal ions for contaminants degradation has received extensive attention in water treatment. There has been growing interest on the mechanism (radical versus non-radical pathway) of activation processes. Interestingly, in contrast to copper, iron or cobalt ions regarded as effective activators for persulfates, manganese ion (Mn(II)) is inefficient for persulfates activation. Inspired by the enhanced stability of manganese species by ligands, this study for the first time systematically investigated the Mn(II)/persulfates with different ligands as a novel oxidation technology. UV-vis spectrometry, chemical probing method and mass spectrometry were used to explore the reactive intermediate (free radical versus high-valent manganese species) therein. It was surprisingly found that the oxidation efficiency of Mn(II)/ligand/persulfates system was highly dependent on the nature of persulfates and ligands. Mn(II) chelated by amino ligands such as ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetate (NTA) could efficiently trigger the oxidation of contaminants (e.g., recalcitrant compounds nitrophenol, benzoic acid and atrazine) by PMS , suggesting a promising Mn(II)/ligand/PMS technology for environmental decontamination especially under manganese-rich conditions. High-valent Mn species (Mn(V)) but not free radicals was demonstrated to be the dominant reactive intermediate, where Mn(III) species played a vital role in Mn(V) generation. The formation of Mn(III) species was found to be affected by the reactivity of persulfates and the type of ligands, thus influencing its further oxidation to Mn(V) species. This study presents a new oxidation process based on the combination of PMS and Mn(II) complex and broadens the knowledge of persulfates activation as well as manganese chemistry for decontamination in water treatment.
研究领域:
环境科学
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水处理技术
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DOI
PubMed
高影响因子
WATER RESEARCH
·
2023
·
IF 12.8
Lin Zhao,Jing Zhang,Jun Ma
Although permanganate (Mn(VII)) is extensively utilized as a strong oxidizer for the purification of water, the direct reaction rates between some refractory pollutants and Mn(VII) are moderate or relatively low. In this study, we found that 2-phenyl-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl (PTIO), could act as a redox mediator to enhance bisphenol A (BPA) degradation by Mn(VII) at pH 5.0 − 9.0, with a removal higher than 80% over 5 min. Moreover, the Mn(VII)/PTIO system is highly efficient toward a broad spectrum of contaminants. Mechanism was elucidated as following: PTIO was oxidized by Mn(VII) to PTIO + , an oxoammonium cation. As a newly generated reactive species, PTIO + could oxidize organics and be reduced to PTIOH (PTIO hydroxylamine) or PTIO simultaneously. The redox cycle of PTIO in consecutive runs as an electron shuttle proved its stability and reusability in Mn(VII) oxidation. In addition to being an electron shuttle, PTIO also acts as an activator of Mn(VII) to promote the production of MnO 2 , which plays a vital role in enhancing BPA abatement at the acidic condition. For the purpose of further understanding the interaction between PTIO and target contaminants, three corresponding degradation pathways for BPA were proposed. Notably, the transformation products of BPA coupling with PTIO were detected, indicating PTIO inhibited the self-coupling of BPA and facilitated the ring-opening pathway. In addition, the ubiquitous humic acid has a positive effect on the Mn(VII)/PTIO system, suggesting a high promise of this system for practical application.
研究领域:
环境化学
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水处理
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污染物降解
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产品关联
DOI
PubMed
高影响因子
Materials Today Physics
·
2024
·
IF 10
Yuping Duan,Meiqi Li,Yuan Guo,Ning Zhu,Huifang Pang,Chenxu Dou
High-entropy alloys, as a novel type of absorber, exhibit exceptional electromagnetic modulation capabilities and significant potential for electromagnetic wave absorption. In this work, the FeCoNiCrMn high-entropy alloy absorbent prepared through a mechanical alloying process demonstrates a dual-phase solid solution structure comprising face-centered cubic (FCC) and body-centered cubic (BCC) phases. By varying the manganese (Mn) content in the system, it is possible to enhance the degree of crystallinity, maintain the integrity of the crystal structure, and effectively control the relative proportion of the BCC phase within the overall phase composition. This adjustment improves the brittleness of the sheet-like particles, reduces particle size, and significantly lowers the permittivity. When the molar ratio of Mn is 0.6, the sample exhibits improved impedance matching due to the optimal permittivity and permeability. Notably, the impedance matching and attenuation constant can also be balanced. At 6.42 GHz, the FeCoNiCr 0.4 Mn 0.6 alloy powder achieves the maximum reflection loss of −48.49 dB at a matching layer thickness of 3 mm. When the matching thickness is reduced to 2 mm, it can effectively cover a frequency range of 8.7–14.1 GHz (effective absorption bandwidth of 5.4 GHz), along with a wide absorption bandwidth and high absorption efficiency.
研究领域:
材料科学
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电磁学
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产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
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2024
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IF 3.2
Bin Cheng,Xiaohui Yan,Junkun Wu,Lunhua He,Wenbin Guo,Xiuyun Lei,Congling Yin,Xiaojun Kuang
Hexagonal perovskite manganite has attracted much attention due to its rich structural chemistry and magnetic properties . The transformation between Ba M x Mn 1− x O 3 polymorphs can be caused by the change in substitution level or oxygen vacancies . In this study, we find a new polymorph change from 10 H Ba 5 Sb 0.7 Mn 4.3 O 15 ( P 6 3 / mmc ) to 12 R Ba 4 Sb 0.85 Mn 3.15 O 12 ( R 3 ‾ m ) via a ‘topochemical’ reaction with excess Sb 2 O 3 . The 10 H Ba 5 Sb 0.7 Mn 4.3 O 15 structure contains BaO 3 layers in a ( cchhh ) 2 sequence and face-shared MnO 6 tetramers (Mn 4 clusters), while the 12 R Ba 4 Sb 0.85 Mn 3.15 O 12 structure consists of BaO 3 layers in a ( cchh ) 3 stacking and face-shared MnO 6 trimers (Mn 3 clusters). The 10 H → 12 R phase conversion accompanies the exsolution of the Mn 3 O 4 phase in trace amounts. For both 10 H Ba 5 Sb 0.71 Mn 4.29 O 15 and 12 R Ba 4 Sb 0.85 Mn 3.15 O 12 , the Mn 3+ cation on the corner-shared octahedra at M 1 sites mediated competing ferromagnetic and antiferromagnetic exchanges between the magnetic Mn 3 and Mn 4 clusters, leading to spin-freezing transition at T F ≈ 11–15 K. The 10 H → 12 R phase change leads to an abrupt change of 2 K saturation moment from M s ≈ 0.1 μ B of 10 H Ba 5 Sb 0.71 Mn 4.29 O 15 to M s ≈ 1.75 μ B of 12 R Ba 4 Sb 0.85 Mn 3.15 O 12 .
研究领域:
材料科学
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固体物理学
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产品关联
DOI
高影响因子
WATER AIR AND SOIL POLLUTION
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2024
·Vol. 235
·期 11
·1-22
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IF 3.8
Zhang Liping,Wang Weiwei,Guo Xiangshuai,Wang Lifang,Chen Jiale,Cui Xingjian,Li Huitong
Iron and Manganese pollution were widespread in the water of northern Chinese mines, exacerbating regional water scarcity and potential ecological issues. This study aimed to remove dissolved iron and manganese from acid mine water using serpentine-loaded manganese oxide (Serp-MO) prepared by a simple coprecipitation-loaded metal method. Serp-MO was microscopically characterized, and the adsorption performance and adsorption mechanism of the Serp-MO composite adsorbent for Fe 2+ and Mn 2+ were analyzed. After loading, the specific surface area and pore volume of the particles significantly increased, and the surface pore structure improved, which was conducive to the simultaneous adsorption and removal of iron and manganese. The optimal reaction conditions for Serp-MO treatment of composite water samples with Fe 2+ and Mn 2+ mass concentrations of 20 mg/L and 5 mg/L respectively, were as follows: dosage of Serp-MO 550 mg/L, temperature 35 ℃, oscillation rate 180 r/min, and reaction time 140 min. Under these conditions, the removal rates of Fe 2+ and Mn 2+ were 99.8% and 99.6%, respectively. The presence of coexistence cations Zn 2+ and Cu 2+ can inhibit the removal of Fe 2+ and Mn 2+ by Serp-MO, while SO 4 2- can promote the removal. The pseudo-second-order kinetic model and Langmuir isothermal adsorption model well described the adsorption process of Fe 2+ and Mn 2+ by the Serp-MO. The maximum adsorption capacities of Serp-MO for Fe 2+ and Mn 2+ were 14.31 mg/g and 24.04 mg/g, representing improvements of 470.12% and 626.28%, respectively, compared to Serp-MO. The adsorption thermodynamics showed that ΔG was <0 and ΔH and ΔS were greater than 0 at all test temperatures, which was an entropy-increasing reaction, and that increasing the temperature was favorable for the removal of Fe 2+ and Mn 2+ . Based on the analysis of adsorption products, Serp-MO primarily facilitates the precipitation of iron in water, while the removal of manganese was mainly by adsorption. A regeneration study over five cycles indicated that Serp-MO possessed promising reusability potential. Furthermore, the safety leaching test indicated that the material caused minimal secondary pollution.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2025
·
IF 6.3
Wenhao Peng,Xin Min,Shiping Luo,Aijuan Xie
Transition metal oxides (TMOs) and sulfides (TMSs) have garnered significant attention as promising electrode materials for supercapacitors due to their complementary properties, including high conductivity, abundant active sites, and structural stability. The rational design and facile synthesis of TMO-TMS hybrid materials with unique architectures are critical to achieving high-performance energy storage devices. This study presents a novel CuMn 2 O 4 @CuMn 2 S 4 core-shell nanostructure developed on a nickel foam substrate through hydrothermal and sulfurization processes. The CuMn 2 O 4 core offers robust structural support and high conductivity, while the CuMn 2 S 4 shell enhances electrochemical activity and ion diffusion. The synthesized material, CuMn 2 O 4 @CuMn 2 S 4 NF-2, achieved a specific capacitance of 760.5 F·g −1 at 1.0 A·g −1 , demonstrating superior electron transfer resistance ( R ct =2.06 Ω) and excellent cycling stability, retaining 85.2 % of capacitance after 5000 cycles. Furthermore, an asymmetric supercapacitor (ASC) with CuMn 2 O 4 @CuMn 2 S 4 NF-2 as the positive electrode and activated carbon as the negative electrode delivered a maximum energy density of 35.31 Wh·kg −1 at a power density of 750 W·kg −1 and retained 75.5 % capacitance after 5000 cycles. This study underscores the significant potential of integrating oxide and sulfide materials in a single architecture, offering a promising pathway for designing high-performance energy storage systems that capitalize on the synergistic properties of both material types.
研究领域:
材料科学
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能源存储
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产品关联
DOI
高影响因子
ENERGY & FUELS
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2020
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IF 3.421
Jun Chen,Yi Chen,Dzmitry Hrynsphan,Yu Mei,Hua Pan,Jiali Wu,Jianmeng Chen,Jiachao Yao
FeII(EDTA) solution has been considered an efficient option in wet flue gas denitrification, whereas the generated FeII(EDTA)–NO restricts its wide application, suggesting that FeII(EDTA)–NO reduction is the key to this process. This work investigated the performance, kinetics, and mechanism of FeII(EDTA)–NO reduction by Mn powder coupled with manganese ion (Mn2+) recovery. We initially studied the performance of FeII(EDTA)–NO reduction with respect to the major influencing factors (i.e., the particle size of Mn powder, initial FeII(EDTA)–NO concentration, Mn powder concentration, stirring speed, and temperature). Shrinking core model and Arrhenius law were applied to illustrate the kinetics and mechanism between FeII(EDTA)–NO solution and Mn powder, suggesting that the solid–liquid reaction was fitted on chemical reaction control, and the activation energy was calculated as 43.0 kJ mol–1. The effects of main operating parameters, such as precipitant concentration, pH value, and temperature, were studied on Mn2+ recovery. Results indicated that the pseudo-second-order model could precisely describe the kinetics of Mn2+ recovery. Finally, according to Arrhenius and Eyring–Polanyi equations, the reaction activation energy, enthalpy of activation, and entropy of activation for Mn2+ recovery were calculated as 17.25 kJ mol–1, 14.55 kJ mol–1, and 252.07 J (k mol)−1, respectively.
研究领域:
环境科学
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化学工程
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产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2019
·Vol. 26
·期 36
·36933-36941
·
IF 2.914
Chen Jun,He Jinjia,Wang Xiaoping,Hrynsphan Dzmitry,Wu Jiali,Chen Jianmeng,Yao Jiachao
Conversion of Fe II (EDTA)-NO or Fe III (EDTA) into Fe II (EDTA) is a key process in a wet flue gas denitrification technology with Fe II (EDTA) solution. In this work, the stoichiometry, kinetics, and thermodynamics of Fe II (EDTA)-NO reduction by Mn powder were investigated. We first studied the Fe II (EDTA)-NO reduction and product distribution to speculate a possible stoichiometry of Fe II (EDTA)-NO reduction by Mn powder. Then, the effects of major influencing factors, such as pH value, temperature, and Mn concentration, were studied. The pseudo-second-order model was established to describe the Fe II (EDTA)-NO reduction. Simultaneously, according to Arrhenius and Eyring-Polanyi equations, the reaction activation energy ( E a ), enthalpy of activation (∆ H ‡ ), and entropy of activation (∆ S ‡ ) were calculated as 23.68 kJ/mol, 21.148 kJ/mol, and − 149.728 J/(k mol), respectively. Additionally, simultaneous reduction of Fe III (EDTA) and Fe II (EDTA)-NO was investigated to better study the mechanism of Fe II (EDTA) regeneration, suggesting that there was a competition between the two reduction processes. Finally, a simple schematic mechanism of NO absorption by Fe II (EDTA) combined with regeneration of manganese ion and ammonium was proposed. These fundamental researches could offer a valuable guidance for wet flue gas denitrification technology with Fe II (EDTA) solution.
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
WATER RESEARCH
·
2019
·
IF 7.913
Jiangkun Du,Guangfeng Xiao,Yanxing Xi,Xiaowei Zhu,Fan Su,Sang Hoon Kim
This study presents a novel periodate oxidation system mediated by manganese oxides for the rapid removal of aqueous contaminants. The catalytic activation of periodate on manganese oxides was demonstrated as an efficient advanced oxidation system for degradation of sulfanilamide. The reactivity of manganese oxides with different Mn valence followed the order of MnO 2 >Mn 3 O 4 >Mn 2 O 3 , all of which showed extraordinary reusability during repeated activation of periodate. Sulfanilamide was rapidly degraded along with stoichiometric transformation of IO 4 − to IO 3 − , and both processes exhibited good linear correlations with the dosage of manganese oxides. While the degradation of sulfanilamide in the MnO 2 /IO 4 − system was accelerated at lower solution pH, it was only slightly affected by ionic strength, water anions and humic acid . In contrast to the homogeneous system of Mn 2+ /IO 4 − , sulfanilamide degradation was not influenced in oxic and anoxic environment. It was evidenced by quenching studies and EPR tests that both singlet oxygen ( 1 O 2 ) and iodate radicals (IO 3 • ) were generated when the metastable Mn(IV)-O-IO 3 interacted with sulfanilamide. The XPS spectra of Mn 2p and O 1s before and after reactions indicated that the catalytic activation of periodate on MnO 2 was not in company with the redox cycling of Mn(IV) species.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Chuanming Zhang,Chunyang Shen,Zhenggang Huang,Hongxin Xu,Yaxiong Zeng,Baohong Guan
Ammonia nitrogen (NH 4 + -N), which exists in the dominant form of ammonium ion (NH 4 + ) under the pH of 6.5–8.5, is one of the regular indexes and the most important pollutants in drinking water. The selective conversion of NH 4 + -N into harmless substances is urgently needed and also a great challenge. Herein we propose a new NH 4 + -N conversion pathway based on a catalytic ozonation process with birnessite-type MnO 2 (δ-MnO 2 ) catalysts. The δ-MnO 2 exhibits a superior performance for NH 4 + -N (1.0 mg/L) removal in adsorption (8.26 %) and oxidation (44.6 %) as well as up to 95.2 % of N 2 selectivity, surpassing almost all the reported O 3 -based catalysts. Unlike the traditional radical oxidation, a singlet oxygen ( 1 O 2 )-dominated nonradical oxidation pathway is confirmed for the efficiently selective conversion of NH 4 + -N to N 2 through the successive dehydrogenation, leading to a 15.0-fold enhancement in NH 4 + -N oxidation rate compared with ozone oxidation. The Mn(III)/Mn(IV) redox sites and surface lattice oxygen in δ-MnO 2 act as the active sites promoting the decomposition of O 3 into •O 2 − and then 1 O 2 via electrons transfer. In application, δ-MnO 2 catalytic ozonation effectively removes NH 4 + -N in real drinking water and presents excellent stability. This work finds a nonradical reaction mechanism in catalytic ozonation for NH 4 + -N selective conversion to N 2 , and solidly solves the problem of low-concentration NH 4 + -N removal from drinking water under the limited pH of 6.5–8.5 condition.
研究领域:
环境科学
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水处理
·
催化
·
污染物去除
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产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Wenwei Tang,Meihuan Tong,Hui Liao,Peiqi Zhang,Xinping Zeng
Aureomycin (CTC) is a commonly used tetracycline antibiotic that causes water and soil pollution and greatly endangers the environment and human health. Microbial degradation to remove residual antibiotics in wastewater is of growing interest. Due to its unique structure and excellent oxidative properties, biogenic manganese oxides (BMO) has been widely studied in the field of water pollutant removal. However, the current preparation of BMO generally suffers from low yield and insufficient production efficiency. In this paper, an efficient manganese-oxidizing bacterium Bacillus sp. D-1 was isolated. Manganese-oxidizing engineering bacteria were constructed to achieve rapid and sufficient BMO production, and the structure and function of the BMO was characterized. SEM was used to characterize the layered structure of the nanoparticles. XPS and XRD were used to determine that the mixture was composed of manganese species with three valence states. BMO was used to degrade 10 mg·L −1 CTC, and the CTC removal rate reached 93.2 % in 24 h, with an optimal reaction pH of 7.6. Finally, LCMS and ECOSAR were used to analyze the oxidative degradation products of CTC and their biological toxicity. Therefore, this paper successfully constructed a high-performance manganese-oxidizing engineering bacterium, revealed the efficient degradation mechanism of CTC by BMO, provided a new strategy for the green treatment of combined pollution of manganese and antibiotics in water bodies, and realized the continuous removal of manganese and water pollutants.
研究领域:
环境微生物学
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环境工程
·
分子生物学
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污染物生物修复
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水处理技术
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）