Journal of Environmental Chemical Engineering
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2024
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IF 7.4
Jia-Yi Liu,Dayong Zhang,Hao Zhou,Xianliang Yi,Yang Liu
A series of pyrolusite-manganite composites with five levels of phosphotungstic acid additions (HPWxMn, x indicating the added mass of phosphotungstic acid) were applied in the catalytic oxidation of 330–350 mg/m 3 formaldehyde under ambient conditions. Different techniques were used to characterize the pristine composite and the best-performed HPW0.2Mn catalyst. Compared to the effects of hydrogen (replacing a small part of structural K + ions) and phosphorus (not detected in the HPW0.2Mn catalyst) elements in phosphotungstic acid, the doping of tungsten would prefer to occur via forming W-O-Mn species, which significantly altered the crystallite growth and induced numerous defects. As to formaldehyde degradation, the best 91% conversion and 72% CO 2 yield were achieved on HPW0.2Mn. The uniqueness of tungsten doping on boosting formaldehyde oxidation was expounded from the angles of intimate elemental interaction (XPS), redox behavior and molecular O 2 activation (CO-TPR, UV-Vis DRS and O 2 -TPD). The incorporation of tungsten led to higher surface Mn 3+ concentration, higher content of surface oxygen vacancies , better low-temperature reducibility and abounding chemically adsorbed oxygen species (They were proposed to be the dominant oxidants for formaldehyde oxidation in this study), which were well correlated with the sequence of catalytic activity. Finally, possible reaction pathways were examined by coupling the characterizations of used catalysts.
研究领域:
环境科学
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催化材料科学
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DOI
高影响因子
Journal of Environmental Chemical Engineering
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2024
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IF 7.4
Huan He,Feiyuan Liu,Zhicheng Liao,Min Shi,Keyu Ma,Shanshan Yang,Bin Huang,Xuejun Pan
Manganese minerals are ubiquitous in aquatic environments, where both inorganic and organic components can form complexes with them, thereby impacting the release of reactive Mn(III) and the fate of pollutants . The available information about these processes remains insufficient, however, impeding the study of the migration and transformation of pollutants in the environment. In this study, pyrophosphate and humic acid were selected as inorganic and organic ligands typical of aquatic environments, and their impacts on the degradation of Bisphenol A by the β- and δ- variants of MnO 2 were investigated. The results indicate that 1.0–5.0 mM pyrophosphate promotes the generation of reactive Mn(III) from β-MnO 2 , resulting in enhanced degradation of Bisphenol A . Pyrophosphate inhibits δ-MnO 2 -mediated degradation of Bisphenol A due to competition for reactive sites. Humic acids increase the degradation of Bisphenol A mediated by δ-MnO 2 by forming complexes with reactive Mn(III) released from the δ-MnO 2 . The degradation of Bisphenol A mediated by minerals in the presence of ligands occurs primarily through hydroxylation , one-electron transfer, and free radical coupling. These findings provide new insights into the role of ligands in the reductive dissolution of manganese minerals and their synergistic effect on the fate of Bisphenol A in aqueous environments.
研究领域:
环境科学
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污染生态学
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产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
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2022
·Vol. 29
·期 47
·71766-71773
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IF 5.19
Huo Junyu,Li Chaoyu,Hu Xiaojin,Xie Huijun,Hu Zhen,Wu Haiming,Liang Shuang,Zhang Jian
Iron ore and manganese ore were used as substrate of constructed wetlands (CWs) to enhance nitrogen (N) removal. However, the N purification performance in CWs filled with iron or manganese ore under antibiotics stress needs further study. In this study, three groups of CWs filled with river sand, limonite (a kind of iron ore), and manganese ore sand were constructed, which were named as C-CWs, Fe-CWs, and Mn-CWs, respectively. The effect and mechanism of the composite antibiotics sulfamethoxazole (SMX) and trimethoprim (TMP) on N removal in CWs were investigated. While the addition of SMX and TMP inhibited about 40% nitrification and promoted about 25% denitrification in all CWs, Fe-CWs and Mn-CWs always had better N removal performance than C-CWs. Changes in microbial community structure in CWs indicated that the better N removal performance in Fe-CWs and Mn-CWs was attributed to the presence of more abundant and diverse N-associated bacteria, especially Fe- and Mn-driven autotrophic denitrifying bacteria. What’s more, the addition of iron ore or manganese ore contributed to the better N removal performance with highest relative abundance of N-transferring bacteria under antibiotics stress.
研究领域:
环境科学
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微生物学
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产品关联
DOI
PubMed
高影响因子
POWDER TECHNOLOGY
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2023
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IF 5.2
Kuixin Cui,Shengming Jin,Nan Duan
The adsorption mechanism of benzohydroxamic acid (BHA) on rhodochrosite surfaces under Pb 2+ activation was systematically studied through a series of experiments. Comparing to the results of only BHA treatment, Pb 2+ ions raised the adsorption amount of BHA and the floatability of rhodochrosite, especially at pH 8.0–9.0. It was proven that Pb(OH) + was deemed as the critical species to adsorb onto rhodochrosite surfaces in the form of lead-containing complexes. Afterwards, rhodochrosite surfaces became much more activated for BHA adsorption. BHA collector reacted with adsorbed-Pb and Mn species of rhodochrosite surfaces, and the charged hydroxamic acid also adsorbed onto rhodochrosite surfaces through electrostatic attraction and co-adsorption. Besides, lead hydroxamate complexes generated in suspension had excellent adhesions on rhodochroganite surfaces. It was apparent that the BHA adsorption was strengthened under the activation of Pb 2+ ions. BHA collector matching with Pb 2+ ions had great potentials to improve the flotation recovery of rhodochrosite.
研究领域:
矿物加工工程
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表面化学
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产品关联
DOI
高影响因子
International Journal of Environmental Science and Technology
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2023
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IF 3.1
Cai Y.,Qiu C.,Yang K.,Tian B.,Bi Y.
Methylene blue is widely used in various industries. The discharge of industrial effluents with methylene blue residues may have hazardous effects on living systems. In this paper, the low-cost, eco-friendly, and abundant geoadsorbent natural manganese ore sand was used as an attractive material to remove methylene blue. The results indicated that the poorly crystalline manganese ore sand could simultaneously adsorb and degrade methylene blue. The pseudo-first-order and MnOII (I) kinetic models could describe the decolorization, but the latter had better predictive characteristics. The kinetics were affected by coexisting substances, but a decolorization efficiency of greater than 80% still could be achieved in actual water matrices. Characterization of manganese ore sand before and after use indicated that the degradation processes that occurred at pH values of 2, 3, 5, 7, and 10 included direct and indirect redox reactions. Specifically, the manganese ore sand behaved primarily as an oxidant at acidic pH, as a catalyst at alkaline pH, and simultaneously as oxidant and catalyst at a neutral pH. Possible degradation routes were proposed based on the suggested intermediates. The main behavior of the oxidant was demethylation of C–CH 3 from methylene blue, and the degree of demethylation increased with decreased pH. As the catalyst, the C–N and C–S bonds on the central heterocycle could be further broken by manganese ore sand after demethylation. The performance of manganese ore sand is related to the content of high-valent Mn species.
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
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
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2015
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IF 1.178
Chang-xin LI,Hong ZHONG,Shuai WANG,Jian-rong XUE,Fang-fang WU,Zhen-yu ZHANG
The extraction of manganese from low-grade manganese oxide ores using CaS derived from CaSO 4 as reductant was investigated. The effects of mass ratio of CaS to ore, reduction temperature, reduction time, liquid to solid ratio (L/S ratio), stirring speed, leaching temperature, leaching time and H 2 SO 4 concentration on the leaching rates of Mn and Fe during the reduction–acid leaching process were discussed. The leaching rates of 96.47% for Mn and 19.24% for Fe were obtained under the optimized conditions of mass ratio of CaS to manganese oxide ore 1:6.7, L/S ratio 5:1, stirring speed 300 r/min, reduction temperature of 95 °C for 2.0 h in the reduction process and leaching stirring speed of 200 r/min, H 2 SO 4 concentration of 1.5 mol/L, leaching temperature of 80 °C for 5 min in the leaching process. In addition, this process can be employed in the recovery of manganese from various manganese oxide ores, and Mn leaching rate above 95% is obtained.
研究领域:
冶金工程
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化学工程
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Kuixin Cui,Nan Duan,Shengming Jin
A novel collector 2-(4-Butoxyphenyl)acetohydroxamic acid (BAHA) was actively considered in the flotation of rhodochrosite. Flotation behaviors and BAHA adsorption concerning rhodochrosite, calcite and dolomite were systematacially investigated through microflotation tests, adsorption experiments, zeta potential measurements, FTIR and XPS analyses. Microflotation results showed that rhodochrosite performed a better floatability than calcite and dolomite at pH 8.0–10.0. Also, the adsorption amounts of BAHA collector on the rhodochrosite surface were obviously greater than those of calcite and dolomite. The results of zeta potential, FTIR and XPS analyses indicated that BAHA adsorbed onto rhodochrosite surfaces through chemisorption, electrostatic attraction and intermolecular hydrogen bonding, chemisorption and electrostatic attraction for calcite, and only chemisorption for dolomite. The interaction mechanisms between BAHA collector and mineral surfaces were responsible for the differences in the BAHA adsorption and floatability between rhodochrosite and two gangues. The flotation separation tests of three minerals confirmed that the rhodochrosite concentrate with Mn grade of 24.64% and recovery of 87.94% could be obtained. BAHA is a high selective collector and can realize the flotation separation of rhodochrosite against dolomite and calcite.
研究领域:
矿物加工工程
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表面化学
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DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2019
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IF 1.911
Dong Sun,Guangzhi Xin,Lu Yao,Lin Yang,Xia Jiang,Wenju Jiang
Manganese leaching during high concentration flue gas desulfurization process with semi-oxidized manganese ore was studied in this paper. It was found that there were different reaction pathways among which MnO 2, Mn 2 O 3 and MnCO 3 in semi-oxidized manganese ore during flue gas desulphurization and manganese leaching. High SO 2 concentration facilitated redox reaction between MnO 2 and SO 2 , and high concentration of H 2 SO 4 accelerated MnCO 3 /Mn 2 O 3 leaching from semi-oxidized ore. Kinetics study showed that manganese leaching in flue gas desulfurization process with semi-oxidized ore was controlled by a mixed-control model, that is the surface chemical reaction and mass diffusion dominated both the oxidation of SO 2 and manganese leaching process. The apparent activation energy was 13.05 kJ·mol −1 and the reaction orders with respect to SO 2 and H 2 SO 4 concentration were 1.38 and 0.10, respectively. Finally, a semi-empirical rate equation based on shrinking core model was derived to describe the process.
研究领域:
化学工程
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环境科学
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产品关联
DOI
高影响因子
LANGMUIR
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2025
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IF 3.9
Ruoyi Chen,Fuding Tan,Xiang Wang,Yuxin Hou,Ming Ouyang,Xingyun Guan,Peng Liu,Zuliang Wu,Shuiliang Yao,Steven L. Suib,Daiqi Ye
The transportation and transformation of biogenic isoprene are vital for the organic carbon cycle in the troposphere. As a typical mineral with high oxidation potential, Fe-substituted cryptomelane oxidizes the surface monolayer of isoprene into formic and acetic acids, and simultaneously, the Mn4+ ions in the structure are reduced to Mn3+ and Mn2+. The flow of H2O in isoprene decreases the adsorption and oxidation of isoprene significantly, even at low relative humidity (10%). As physisorbed H2O retains Fe-substituted cryptomelane’s crystal structure and oxidation ability, the adsorption and oxidation capacity recovers when H2O is absent in the isoprene flow. Theoretical calculations on (001) surfaces show that isoprene prefers to be adsorbed by the Fe3+ site and H2O tends to form hydrogen bonds. Due to the decrease in total adsorption energy of H2O and isoprene, Fe-substituted cryptomelane favors the adsorption of H2O in the flow of humid isoprene. The low oxidation performance at ambient relative humidity suggests that direct oxidation by aerosols of mineral dust might not be the transformation pathway of biogenic isoprene at night.
研究领域:
大气科学
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环境化学
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DOI
PubMed
高影响因子
Catalysis Science & Technology
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2025
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IF 4.2
Xiaohui Wang,Zhuang Li,Peng Zhao,Chao Yao,Jie Meng,Shixiang Zuo,Wei Zhu,Jingwei Liu,Fengqin Wu
Natural manganese ore (NMO) has received extensive attention on account of its inherent stability, abundant reserves, and low cost. The higher specific surface area and abundant active sites are considered crucial for catalytic combustion. However, owing to the limited specific surface area inherent to natural manganese ore, we employed an acid etching activation treatment to enlarge the specific surface area of NMO (from 17.8 m2 g−1 to 48.9 m2 g−1). Herein, we successfully fabricated composite catalysts consisting of activated natural manganese ore (HNMO) and Co3O4 using the ethylene glycol sol–gel method and then evaluated them for the catalytic combustion of ethane. Results showed that the catalytic performance of the composite catalysts for ethane could not be enhanced monotonically by increasing the introduction of Co indiscriminately. Among them, the Co2-HNMO catalyst exhibited a higher specific surface area, increased Mn4+ and Co3+ contents and higher oxygen mobility, which were attributed to the significant interaction between Co3O4 and HNMO. The T90 of the corresponding Co2-HNMO catalyst was 294 °C under a space velocity of 40 000 mL g−1 h−1. This work presents new insights into the design and synthesis of efficient composite catalysts based on natural minerals.
研究领域:
化学工程
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催化材料科学
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DOI
高影响因子
Journal of Water Process Engineering
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2025
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IF 6.7
Shilong Wang,SuNa Wang,Weiyi Zhao,Shiyu Fang,E. Yang,Runze Xu,Fang Fang,Weijing Liu,Jiashun Cao,Song Cheng
Recovering phosphorus (P) from wastewater benefits both the environment and the field of clean energy. Vivianite is a key precursor for clean energy lithium batteries, making it a highly valuable and promising product in wastewater P recovery. As a widely used cathode material in lithium-ion batteries, LiFePO 4 is valued for its excellent thermal stability, safety, and long cycle life, making it a promising material for sustainable energy applications. However, the large amount of aluminium (Al) present in the recirculated sludge can be released into the supernatant during the anaerobic digestion process, which affects the recovery of vivianite and further impacts the performance of LiFePO 4 . This study investigated the effect of Al on vivianite crystallization throughout the P recovery process and explored the direct synthesis of LiFePO 4 using Al-containing vivianite. Varying initial Al concentrations were examined to understand their influence on the crystallization kinetics, purity, and morphology of vivianite. At low Al concentrations (1–50 mg/L), Al formed amorphous aluminium phosphate that attached to vivianite crystals via electrostatic interactions and surface adsorption. At high Al concentrations (100–300 mg/L), Al predominantly entered the solid phase through co-precipitation, significantly inhibiting vivianite formation. LiFePO 4 /C cathode materials were synthesized using the recovered Al-containing vivianite. The results revealed that Al existed as inert substances within LiFePO 4 /C, reducing its crystallinity and specific discharge capacity. These findings elucidate how Al affects vivianite crystallization during P recovery and provide theoretical insights for converting Al-containing vivianite into value-added LiFePO 4 .
研究领域:
环境科学
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能源材料科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
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IF 7.312
Zhihui Shen,Qin Zhang
Efficient separation of fine-disseminated rhodochrosite is a challenge in the purification of manganese carbonate ore and a key to reduce the discharge of electrolytic manganese slag. The agglomeration behavior of the fine particles is of importance for flotation separation. In this study, we investigated the agglomeration behavior and aggregate properties of rhodochrosite fines co-induced by oleic acid (OA) and shearing using particle size and structure analysis, surface properties measurement, extended DLVO (EDLVO) theoretical calculation and shear fracture model analysis. The results showed that rhodochrosite fines agglomerates obviously with the increasing OA concentration and pH value, and the average particle size reaches the maximum at the initial OA concentration of 1 × 10 -3 mol/L and pH of 6. The monolayer physical and chemical saturation adsorption of OA cause stronger hydrophobicity of rhodochrosite. Meanwhile, the hydrophobic attractive force between particles is stronger than electrostatic repulsive force, resulting in hydrophobic agglomeration. The moderate stirring rate is conducive to forming larger-sized and denser agglomerates with the critical rate of 500 rpm. However, intensive shearing will cause significant damage to the formed agglomerates. Besides, the volume concentrations of 10–30 μm and 30–45 μm particles increased with the increase of stirring rate after breakage and with a lower value of γ’ than 0.5, suggesting that the agglomerates breakage is mainly controlled by large-scale fragmentation mechanism. Interestingly, as recovering shearing from the higher rate to the initial rate, a secondary agglomeration is achieved by the regrowth of core (30–45 μm particles) and attach of branches and coatings (some < 10 μm and 10–30 μm particles) under the synergy of hydrophobic attraction and shearing. However, it did not fully recover back to the original balanced state before fragmentation, which was due to irreversible damage caused by excessive shearing. This research will be beneficial for in-depth understanding of agglomeration mechanisms of rhodochrosite fines and provide a basis for subsequent efficient flotation separation.
研究领域:
矿物加工
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胶体与界面化学
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资源利用技术
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环境工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）