ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
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2015
·Vol. 23
·期 4
·3609-3620
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IF 2.828
Su Pingru,Zhu Huicen,Shen Zhemin
Manganese dioxide formed in oxidation process by potassium permanganate exhibits promising adsorptive capacity which can be utilized to remove organic pollutants in wastewater. However, the structure variances of organic molecules lead to wide difference of adsorption efficiency. Therefore, it is of great significance to find a general relationship between removal rate of organic compounds and their quantum parameters. This study focused on building up quantitative structure activity relationship (QSAR) models based on experimental removal rate ( r
exp ) of 25 organic compounds and 17 quantum parameters of each organic compounds computed by Gaussian 09 and Material Studio 6.1. The recommended model is r
pre = −0.502 − 7.742 f (+) x + 0.107 E
HOMO + 0.959 q (H + ) + 1.388 BO
x . Both internal and external validations of the recommended model are satisfied, suggesting optimum stability and predictive ability. The definition of applicability domain and the Y-randomization test indicate all the prediction is reliable and no possibility of chance correlation. The recommended model contains four variables, which are closely related to adsorption mechanism. f (+) x reveals the degree of affinity for nucleophilic attack. E
HOMO represents the difficulty of electron loss. q (H + ) reflect the distribution of partial charge between carbon and hydrogen atom. BO
x shows the stability of a molecule.
研究领域:
环境科学
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化学
✓ 已验证
DOI
高影响因子
Surfaces and Interfaces
·
2025
·
IF 6.3
Jun Hua,Xianwen Wu,Fangxi Xie,Mingmei Wu
Manganese-based aqueous zinc-ion batteries are considered to be one of the most promising candidates owing to its abundant resources, environmental friendliness and high safety. However, some severe problems associated with cathode are mainly plagued by Mn (III) disproportionation and Jahn-Teller distortion, leading to undesired manganese dissolution and reduced their cycle life. Herein, Cr-doped δ-MnO 2 is synthesized by a simple hydrothermal method. This study demonstrates how Cr-doping addresses these challenges by narrowing the lattice spacing between MnO 2 layers, promoting self-confinement, and mitigating Mn 2+ dissolution. As a result, Cr-doped δ-MnO 2 exhibits enhanced crystal structure stability, with superior capacity retention of 65.80 % compared to 51.53 % for pristine δ-MnO 2 after 300 cycles at 500 mA/g. Our findings provide an alternative avenue for mitigating Mn dissolution, laying the groundwork for the adoption of Zn/MnO 2 batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Qian Liu,Liying Wang,Guohua Chen,Gaoqi Wu,Jingjing Wang,Zhiwei Liu,Zhenzhu Cao,Yongfeng Zhang
Transition metal sulphides and oxides have been identified as potential cathode materials for lithium-ion batteries with high initial capacity and high selectivity. Nevertheless, the low ground conductivity and volume expansion have constituted significant obstacles to the advancement of this field of study. In this study, the heterostructure CoMn₂O₄/MnS₂@C1-2-2 of MnS₂ and CoMn₂O₄ was obtained through high-temperature (Ar. 450 °C) calcination of a novel red single crystal [CoMn(TDC)] n precursor. The resulting structure exhibited excellent lithium-ion transport properties. The biphasic heterostructure with a porous carbon framework is capable of forming a multitude of phase interfaces and conductive pathways, which facilitate charge migration, enhance conductivity, and expand the contact area with the electrolyte, thereby augmenting the charge transfer capability. The CoMn 2 O 4 MnS 2 @C1-2-2 composite displays remarkable lithium storage capabilities, with a specific capacity of 689 mA h g −1 even after 400 cycles at 0.5 A g −1 .
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Guocan Zheng,Yingchun Zhang,Qinrui Du,Yingxia Zhang,Kehao Wang,Jingxiao Du
Electrolytic manganese residue (EMR) represents a solid waste generated during the production of electrolytic manganese. Under the leaching and dissolution by rainwater, manganese, ammonia nitrogen, and heavy metal ions in EMR can infiltrate into the surrounding environment, thereby disrupting ecological balance and posing threats to human health. This study optimized the leaching conditions for manganese from EMR using ammonium persulfate(APS) through single-factor and orthogonal experiments. It was found that temperature, APS concentration, and reaction time significantly influenced the manganese leaching efficiency. Under leaching temperature of 80°C, leaching time of 3 hours, APS concentration of 30 g/L, and a liquid-to-solid mass ratio of 6 mL/g, a high manganese leaching rate of 88.91 % was achieved in a single process, and significant removal of ammonia nitrogen was observed. After enhanced leaching, the content of organic matter and the total amount of water-soluble salt were 4.10 wt% and 3.11 wt%, respectively. And it meets the requirements of the standard GB 18599–2020 for solid waste entering the class II site in China. Kinetic analysis revealed that the manganese leaching process was controlled by intraparticle diffusion within the solid phase. Mineralogical phase analysis indicated that the primary mineral structures were oxidatively decoupled and disrupted, leading to the dissociation of aggregates, which facilitated the leaching of manganese and ammonia nitrogen. This study provides a practical, green, and economical technological route for the harmless treatment of EMR.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Hongtao Wu,Gaole Yan,Xiangyue Liu,Gang Yang
Manganese-based lithium-ion sieves (LISs) exhibit remarkable potential for lithium extraction from salt lakes owing to their excellent adsorption properties and high selectivity. However, manganese dissolution severely limits the industrial application of manganese-based LISs. Herein, a series of molybdenum (Mo)-doped manganese-based LISs (LMMO-X%) with high adsorption capacity were synthesised using the sol-gel method. Results indicate that the introduction of Molybdenum atom enhances the Mn(IV) content in the material while promoting the growth of the (111) crystal plane of Li 4 Mn 5 O 12 and suppressing the growth rates of the (110) and (100) crystal planes. Compared to the undoped ion sieve, the lithium adsorption capacity of the Mo-doped material increased from 35.56 to 44.63 mg/g, while the manganese dissolution rate decreased from 3.79 % to 2.63 %, considerably improving the overall performance of the LIS adsorbent. X-ray diffraction and X-ray photoelectron spectroscopy confirmed that Mo was successfully doped into the material, increasing the Mn(IV) content from 35.3 % to 56.5 %, enhancing the structural stability of the material and alleviating the Jahn–Teller distortion during the acid elution process. In addition, the adsorption process follows a pseudo-second-order kinetic model and the Langmuir isotherm adsorption model. In competitive salt solutions, LMMO demonstrates excellent selectivity for Li + and retains 80.73 % of its adsorption capacity after 10 cycles. This study provides a novel strategy for enhancing the structural stability of doping-modified materials.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Tao Jin,Xiling Ye,Zhuo Chen,Shuai Bai,Yining Zhang
Aqueous zinc-ion batteries have attracted attention due to their low cost and high safety. Unfortunately, dendrite growth, hydrogen evolution reactions, cathodic dissolution, and other problems are more serious; not only that, but also the cathodic and anodic materials’ lattices contract when the temperature drops, and charge transfer and solid phase diffusion become slow, seriously aggravating dendrite growth. At present, there are few studies on the low-temperature system, and studies on retaining high specific capacity are even more rare. Herein, ethylene glycol (EG) and manganese sulfate (MSO) are selected as additives, and the manganese vanadate (MVO) cathode is used to find a high-performance solution at low temperature. MVO can provide higher specific capacity and better structural stability than MnO2 to adapt to a low-temperature environment. At the same time, Mn2+ in MSO can produce a cationic shield covering the initial zinc tip at an appropriate concentration to avoid the tip effect and inhibit the dissolution of MVO. EG can not only reduce the freezing point of the electrolyte but also promote the desolvation of [Zn(H2O)6]2+. The synergistic effect of the three elements prevents the dissolution equilibrium of Mn2+ in MVO from fluctuating greatly due to the change of temperature. Therefore, when we use EG@0.2 M MnSO4 + 2 M ZnSO4 (EG + 0.2Mn/2ZSO) electrolyte at −30 °C, the Zn||Zn batteries which used this type of electrolyte can remain 350 h at 1 mA cm–2 without failure. The Zn||Cu batteries can retain 100% Coulombic efficiency after more than 2000 cycles at 0.2 mA cm–2. The Zn||MVO battery can reach 231.13 mA h g–1 at its first cycle, and the capacity retention rate is still above 85% after 1000 cycles, which is higher than that of the existing low-temperature research system.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Bo Sun,Yiqiao Zhang,Zhaoyu Gong,Jian Zhang,Jing Zhang
Permanganate is one of common oxidants used for organic pollutant abatement in water treatment . This study showed that the degradation rate of bisphenol A (BPA) by permanganate at pH 5.0 in the presence of aniline is much higher than that in the absence of aniline. 2, 5, and 10 μM of aniline enhanced BPA degradation rate by 104%, 326% and 601%, respectively. Colloidal MnO 2 was formed through the reduction of permanganate by aniline and contributed to BPA oxidation considerably. The reactivity of MnO 2 is sensitive to pH and is high under acidic conditions, resulting in the observed enhancement of aniline on BPA removal by permanganate at pH < 7.0. The role of MnO 2 was further confirmed by the relationship of MnO 2 formation and BPA/aniline removal, the inhibitory effect of Ca 2+ on the oxidation of BPA in the presence of aniline. Besides the aniline/BPA system, the pollutants which react with permanganate rapidly are likely to enhance the degradation of coexisting pollutants which show high reactivity towards MnO 2 . Due to the reduction of permanganate and stabilization of the in situ formed colloidal MnO 2 by water matrix, the oxidation rate of pollutant in real water is higher than that in pure water.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Ruifeng Zhang,Chuanyun Yang,Qiuyan Niu,Jing Yang
Finding a low-cost and high effective catalyst is an important problem in advanced oxidation processes (AOPs) based on PMS for organic matter removal. In this study, manganese oxide (MnO x ) was extracted from the backwashing sludge of a filter for manganese removal and used to activate peroxymonosulfate (PMS) to remove humic acid from water. It was found that thermal treatment had significant effects on the structure and catalytic activity of MnO x . When MnO x was treated at 500 °C, it showed excellent catalytic activity and the removal rate of HA was up to 81.0%. Characterization indicated that the MnO x was converted from buserite and birnessite to α-MnO x after treated at 500 °C, and the specific surface area and the percentage of Mn (III) and O latt on the surface increased significantly. The repeated utilization experiments indicated that the extracted MnO x still had high activity after reusing for 5 cycles. Quenching experiments showed that 1 O 2 was the dominant reactive oxygen species to oxidize HA in water. Finally, combining the results of FTIR and XPS spectra of MnO x before and after the catalytic reaction , the reaction mechanism was proposed: PMS was activated to be 1 O 2 by Mn (III) and O latt in MnO x with a valence transformation between Mn (II), Mn (III) and Mn (IV) and HA was mainly oxidized by the non-radical pathway through 1 O 2 . The experiments will provide a new strategy for recycling MnO x from backwashing sludge of the filter for Mn 2+ removal to remove natural organic matter from water.
研究领域:
环境科学
·
水处理工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2024
·
IF 7.1
Jinpeng Cao,Kaifeng Yu,Jianing Zhang,Biao Lu,Juezhi Yu,Shiqiang Huang,Feifei Zhang
Aqueous manganese redox flow batteries (AMRFBs) that rely on the two-electron transfer reaction of Mn2+/MnO2 have garnered significant interest because of their affordability, high voltage, and excellent safety features. Nevertheless, the deposited MnO2 tends to partially dissolve during discharge, impeding the sustained operation of AMRFBs, particularly at high areal capacities (>5 mA h cm–2). Herein, VO2+/VO2+ was introduced into the catholyte as a redox mediator (RM) to facilitate the efficient dissolution/deposition process of MnO2. In situ UV–vis spectroscopy and kinetic analysis elucidated the swift reaction mechanism between MnO2 and VO2+, which allows for efficient rejuvenation of “dead” MnO2 with facile amounts of mediator, further achieving a highly reversible MnO2 cathode. The assembled zinc–manganese redox flow battery with RM demonstrates a high Coulombic efficiency of 99% at 20 mA h cm–2 over 50 cycles. The areal capacity is further increased to 50 mA h cm–2, achieving an exceptional areal energy density exceeding 100 mW h cm–2, surpassing most reported areal capacity in the AMRFB. This work introduces a novel RM to address “dead” MnO2 and sheds valuable insights into the reaction mechanism between MnO2 and RM, which will promote the development of other deposition-type batteries.
研究领域:
电化学
·
能源材料科学
✓ 已验证
DOI
高影响因子
RESOURCES CONSERVATION AND RECYCLING
·
2021
·
IF 10.204
Shun Zhang,Shiyu Miao,Xiaoqiang An,Huachun Lan,Ruiping Liu,Jianfeng Peng,Huijuan Liu,Jiuhui Qu
Many efforts have been made to improve the dewaterability during anaerobically digested sludge (ADS) conditioning. However, the conversion of substances in ADS conditioning, as an important process of sludge treatment and application, has received little attention. This study investigated the transformation process of typical components in sludge such as extracellular polymeric substances (EPS), sulfide, Fe and Mn species. The effects of KMnO 4 dosage and pH change on the ADS conditioning were investigated in detail. The results showed that the sludge particle size and capillary suction time decreased with the increase of KMnO 4 dosage. The water content of sludge cake by vacuum filtration gradually dropped from 84.5% to 78.8% after conditioning with 0–5.0 g KMnO 4 /L sludge. Based on fluorescence excitation-emission matrix, EPS and dissolved organic carbon measurements, the improvement of sludge dewaterability was due to the disruption of EPS and the release of intracellular substances. Interestingly, 11.5% sulphides (S 2− ) in ADS were oxidized into SO 4 2− at KMnO 4 dosage of 3.0 g/L, which can effectively inhibit the release of hazardous H 2 S even the sludge pH changed to 2 in conditioning process. Moreover, about 30 mg/L of PO 4 3− in centrifugate can be completely immobilized by the generated iron, manganese and their binary oxides as a result of the interaction between Fe 2+ and KMnO 4 . These findings provided a new insight to explore the sludge conditioning process and the transformation of typical components.
研究领域:
环境科学
·
污水处理
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Energy Research
·
2020
·
IF 2.746
Zhou Weijun,Wang Anran,Huang Aixiang,Chen Minfeng,Tian Qinghua,Chen Jizhang,Xu Xinwu
With the advantages of intrinsic safety, low price, high output potential, and acceptable energy density, aqueous rechargeable Zn–MnO2 batteries are gradually emerging as promising energy storage devices in recent years. Unfortunately, the structural instability and poor electrical conductivity of manganese dioxides still hinder their further applications. To tackle these issues, we demonstrate a high-performance cathode material for Zn–MnO2 batteries by hybridizing lignin-derived porous carbon with δ-MnO2 (denoted as LPC/δ-MnO2). Benefiting from the high electrical conductivity of porous carbon, the LPC/δ-MnO2 cathode material can offer high discharge capacity of 332.3 mAh g–1 at 0.2 A g–1 and excellent high-rate capability (196.1 mAh g–1 at 5 A g–1). Meanwhile, the assembled Zn–MnO2 battery displays good long-term cycling stability (82% capacity retention after 1000 cycles). Such superior performances are attributed to the synergetic effect of nanostructured δ-MnO2 and porous carbon scaffold, which is in favor of rapid Zn2+ ion diffusion and large contribution ratio of pseudocapacitive Zn2+ ion intercalation. The results of this study show great prospects of hybridizing biomass-derived carbon framework with electrochemically active materials toward advanced energy storage materials.
研究领域:
材料科学
·
能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2015
·
IF 5.33
Bo Sun,Xiaohong Guan,Jingyun Fang,Paul G. Tratnyek
MnO4– was activated by HSO3–, resulting in a process that oxidizes organic contaminants at extraordinarily high rates. The permanganate/bisulfite (PM/BS) process oxidized phenol, ciprofloxacin, and methyl blue at pHini 5.0 with rates (kobs ≈ 60–150 s–1) that were 5–6 orders of magnitude faster than those measured for permanganate alone, and ∼5 to 7 orders of magnitude faster than conventional advanced oxidation processes for water treatment. Oxidation of phenol was fastest at pH 4.0, but still effective at pH 7.0, and only slightly slower when performed in tap water. A smaller, but still considerable (∼3 orders of magnitude) increase in oxidation rates of methyl blue was observed with MnO2 activated by HSO3– (MO/BS). The above results, time-resolved spectroscopy of manganese species under various conditions, stoichiometric analysis of pH changes, and the effect of pyrophosphate on UV absorbance spectra suggest that the reactive intermediate(s) responsible for the extremely rapid oxidation of organic contaminants in the PM/BS process involve manganese(III) species with minimal stabilization by complexation. The PM/BS process may lead to a new category of advanced oxidation technologies based on contaminant oxidation by reactive manganese(III) species, rather than hydroxyl and sulfate radicals.
研究领域:
环境科学
·
化学工程
✓ 已验证
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）