JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2014
·
IF 3.552
X. Ge,C.D. Gu,X.L. Wang,J.P. Tu
Manganese oxides with desired structure are controllably obtained through annealing MnCO 3 precursors with required structures. The structures of MnCO 3 precursors are determined by a “mesocrystal formation” process in an ionic liquid system of a choline chloride/urea (CU) mixture. Without addition of surfactants, only CU solvent and manganese chloride are needed in the reaction system, in which the CU acts as reaction medium as well as control agent for particle growth. A shape transformation of MnCO 3 particles from well-defined rhombohedral mesocrystals to ellipsoidal polycrystal ensembles, and to nanoparticulate aggregates is observed when heating the reaction system for 4 h at 120, 150, and 180 °C, respectively. With a longer aging time at 120 °C, etching and disassembly of MnCO 3 mesocrystals happened. The correlation between the microstructure and the underlying formation mechanism is highlighted. Porous and nanowire-like MnO x nanostructures are obtained through a facile thermal conversion process from the diverse MnCO 3 precursors, which are demonstrated as effective and efficient adsorbents to remove organic waste (e.g. Congo red) from water. Significantly, the nanowire-like MnO x nanostructures obtained by annealing the MnCO 3 mesocrystals at 300 °C for 4 h can remove about 95% Congo red in waste water at room temperature in only one minute, which is superior to the reported hierarchical hollow nanostructured MnO 2 .
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2016
·
IF 4.917
Chunyan Li,Shuting Wang,Xiaopeng Du,Xiaosong Cheng,Meng Fu,Ning Hou,Dapeng Li
In this study, three bacteria with high Fe- and Mn-oxidizing capabilities were isolated from groundwater well sludge and identified as Acinetobacter sp., Bacillus megaterium and Sphingobacterium sp. The maximum removal ratios of Fe and Mn (99.75% and 96.69%) were obtained by an optimal combination of the bacteria at a temperature of 20.15 °C, pH 7.09 and an inoculum size of 2.08%. Four lab-scale biofilters were tested in parallel for the removal of iron and manganese ions from groundwater. The results indicated that the Fe/Mn removal ratios of biofilter R4, which was inoculated with iron- and manganese-oxidizing bacteria and a biofilm-forming bacterium, were approximately 95% for each metal during continuous operation and were better than the other biofilters. This study demonstrated that the biofilm-forming bacterium could promote the immobilization of the iron- and manganese-oxidizing bacteria on the biofilters and enhance the removal efficiency of iron and manganese ions from groundwater.
研究领域:
微生物学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2016
·Vol. 41
·期 2
·677-684
·
IF 3.277
Shaqi Ge,Ka Wai Wong,Ka Ming Ng
Digenite Cu1.8S and covellite CuS nanoparticles can both be obtained through the hot-injection synthetic process by controlling the synthesis temperature and time. Compared with digenite Cu1.8S, covellite CuS attracts more attention due to the extraordinary LSPR effect. However, digenite Cu1.8S is thermally more stable and suitable for applications at elevated temperature. In this work, LSPR was found to be induced by incorporation of manganese (Mn) into originally weakly absorbing digenite Cu1.8S nanoparticles. In addition, it was observed that the intensity of the LSPR effect could be controlled by tuning the manganese content in the new Mn-incorporated digenite Cu1.8S (CuxMnyS) nanoparticles.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
·
2024
·
IF 1.6
Hao Yan,Wenhua Tong,Jiepeng Wang,Panyu Li,Xuqian Wang,Yongkui Zhang
Waste sulphur produced in industrial processes is often exposed to the air, and its diffusion and combustion in the environment can produce harmful substances, posing a significant risk to ecological safety and human health. Herein, a novel method for the direct treatment of solid sulphur with manganese dioxide based on a simple sealed reactor is proposed. Significantly, the developed sulphur treatment technology could prepare high purity manganese sulphate at the same time. Under the optimum conditions of the reaction temperature of 187.2°C, reaction time of 21.6 h, sulphuric acid loading of 1.00 mol ∙ L −1 , and manganese dioxide dosage of 4.00 mol ∙ mol-S −1 derived by the response surface method (RSM), the removal efficiency of sulphur could reach near 100%, and the purity of the manganese sulphate product obtained was more than 98%. Kinetic model fitting analysis and several characterization methods were adopted to confirm that the reaction process between sulphur and manganese dioxide follows the unreacted nuclear model controlled by surface chemical reaction, and the transformation paths of Mn and S elements were proposed. This study provides a novel method for the resource treatment of waste sulphur and the preparation of high purity manganese sulphate.
研究领域:
环境科学
·
材料化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
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
·
催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 21
·52199
·
IF 3.057
Wenjiao Wang,Mingming Zheng,Jiajia Ren,Mingliang Ma,Xunqian Yin,Tingxi Li,Yong Ma
Magnetic Fe 3 O 4 /MnO 2 /TiO 2 /polypyrrole (PPy) heterostructure as adsorbent for adsorbing Mn 7+ was synthesized by combining hydrothermal method and chemical oxidation method. The heterostructure was characterized by field-emission scanning electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, and vibrating sample magnetometer. Its saturation magnetization is 18.88 emu/g, so it is easy to separate it from the solution. The feasibility of Fe 3 O 4 /MnO 2 /TiO 2 /PPy heterostructure to remove Mn 7+ was researched in detail. It is found that the optimal pH is 2. The initial adsorption rate can reach 4.60 mg/g min. At 288.15 K, the maximum equilibrium adsorption capacity is 202.8 mg/g. Adsorption kinetics follows a pseudo second order model, as well as is determined by through membrane diffusion processes. The Langmuir isotherm model is used to describe the adsorption isotherm behavior. Besides, thermodynamic parameters indicate spontaneous adsorption behavior, and entropy of the endothermic reaction increases. Finally, the cycle test results show that the adsorbent has better cycle performance, displaying broad application prospects.
研究领域:
环境科学
·
材料科学
·
化学工程
·
纳米技术
·
污染控制
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2023
·Vol. 13
·期 10
·1600
·
IF 5.3
He Zhang,Ruixue Xiong,Shijie Peng,Desheng Xu,Jun Ke
In this paper, high-activity manganese oxide was prepared from electrolytic manganese anode slime to realize the efficient removal of antibiotics. The effects of sulfuric acid concentration, ethanol dosage, liquid–solid ratio, leaching temperature and leaching time on the leaching of manganese from electrolytic manganese anode slime were systematically studied. Under the optimal conditions, the leaching rate of manganese reached 88.74%. In addition, a Mn3O4catalyst was synthesized and used to activate hydrogen persulfate (PMS) to degrade tetracycline hydrochloride (TCH). The synthesized Mn3O4was characterized by XRD, XPS, Raman, SEM and HRTEM. As a result, the prepared Mn3O4is spherical, with high purity and crystallinity. The catalytic activity of Mn3O4for PMS to degrade TCH was increased to 82.11%. In addition, after four cycles, the performance remained at 78.5%, showing excellent stability and recyclability. In addition, O2−and1O2are the main active species in the degradation reaction. The activity of Mn3O4is attributed to it containing Mn(II) and Mn(III) at the same time, which can quickly realize the transformation of high-valence and low-valence manganese, promote the transfer of electrons and realize the degradation of organic pollutants.Keywords:solid waste recycling;electrolytic manganese anode slime;manganese oxide;antibiotics;advanced oxidation process
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
CHEMOSPHERE
·
2020
·
IF 5.778
Zhao-Feng Yuan,Williamson Gustave,John Boyle,Raju Sekar,Jonathan Bridge,Yuxiang Ren,Xianjin Tang,Bin Guo,Zheng Chen
The sharp redox gradient at soil-water interfaces (SWI) plays a key role in controlling arsenic (As) translocation and transformation in paddy soils . When Eh drops, As is released to porewater from solid iron (Fe) and manganese (Mn) minerals and reduced to arsenite . However, the coupling or decoupling processes operating within the redox gradient at the SWI in flooded paddy soils remain poorly constrained due to the lack of direct evidence. In this paper, we reported the mm-scale mapping of Fe, As and other associated elements across the redox gradient in the SWI of five different paddy soils. The results showed a strong positive linear relationship between dissolved Fe, Mn, As, and phosphorus (P) in 4 out of the 5 paddy soils, indicating the general coupling of these elements. However, decoupling of Fe, Mn and As was observed in one of the paddy soils. In this soil, distinct releasing profiles of Mn, As and Fe were observed, and the releasing order followed the redox ladder. Further investigation of As species showed the ratio of arsenite to total As dropped from 100% to 75.5% and then kept stable along depth of the soil profile, which indicates a dynamic equilibrium between arsenite oxidization and arsenate reduction. This study provides direct evidence of multi-elements’ interaction along redox gradient of SWI in paddy soils.
研究领域:
土壤学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Tian Wang,Xufang Qian,Dongting Yue,Xuan Yan,Hiromi Yamashita,Yixin Zhao
Perovskite oxides ABO 3 with unique structure showed promising performance on persulfates activation. Previous research works mainly focused on Co-based or rare earth metal (La, Sr)-based perovskite oxides for peroxymonosulfate (PMS) activation. Here, we firstly studied perovskite CaMnO 3 metal oxide composed with the low cost and eco-friendly Ca and Mn elements for PDS activation. Perovskite CaMnO 3 metal oxide achieve the superior catalytic activity for reactive oxygen species generation than the regular Mn oxides (β-MnO 2 and Mn 2 O 3 ) and other types Ca x Mn y O z (spinel-type CaMn 2 O 4 and Ca 2 MnO 4 ) solid solution due to the tolerance of Mn multivalence and defects in the perovskite structure and the excellent Mn 3+ /Mn 4+ redox capacity in CaMnO 3 . The CaMnO 3 /PDS system could be applied at a wide pH range from 4 to 12, and exhibited better performance in basic conditions. Different active species including SO 4 − , OH reactive radicals and singlet oxygen 1 O 2 were found and responsible for effective pollutants degradation. Our study shows eco-friendly perovskites possess great potential in the refractory organic pollutants removal by catalytic activation of PDS.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2024
·Vol. 171
·期 5
·050541
·
IF 3.1
Ye-ba Yan,Yue Fang,Jia-liang Wang,Heng-xue Zhou,Yi Long,Bo Liang,Ying-bang Yao,Libin Tian,Sheng-guo Lu,Tao Tao
Due to a lack of portable flexible power supply, flexible electronic products can still not be applied in a large scale, particularly in the high energy density devices. To resolve this issue, flexible solid-state lithium batteries with a high safety, excellent mechanical property, and high energy densit，is proposed. In this paper, a flexible solid-state lithium-manganese battery is developed, which is assembled with a lithium cloth composite anode, a composite solid-state electrolyte poly (vinylidene fluoride)-hexafluoropropylene (PVDF-HFP)/Li6.4La3Zr1.4Ta0.6O12 (LLZTO), and a composite cathode (Fe ion-doped MnO2-carbon cloth). To improve the conductivity and stability of cathode, a mixture of conductive carbon black (Super P) and sodium alginate (SA) is employed. To ensure the high capacity and low price, the MnO2-based cathode is used.The obtained solid state batteries can deliver an initial capacity of 275.9 mAh g−1 at a current density of 1 C and a capacity retention of 57.9% (159.7 mAh g−1) after 1000 cycles. Also the produced flexible punch cell can light up the light-emitting diode(LED), and its capacity is 0.58 mAh cm−2 after 100 cycles at current density of 0.2 C.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Fan Feng,Suli Chen,Shiqiang Zhao,Wenli Zhang,Yigao Miao,Haiying Che,Xiao-Zhen Liao,Zi-Feng Ma
Sodium manganese hexacyanoferrate (PBM) is one of the most promising cathode materials for sodium-ion batteries due to its high theoretical capacity, high voltage, and low cost. However, its cycling performance is limited by serious Mn ions dissolution during Na + insertion/extraction. In this work, a facile in situ ion-exchange strategy is developed to synthesize sodium manganese hexacyanoferrate coated by sodium nickel hexacyanoferrate (PBM@PBN). The as-prepared PBM@PBN showed superior cyclic stability and enhanced rate capability. PBM@PBN exhibited a high reversible capacity of 126.9 mAh g −1 (1 C), with a capacity retention of 74.3% after 800 cycles. ICP results proved that superior cyclic stability was attributed to the inhibition of Mn ions dissolution by PBN coating. Besides, PBM@PBN also exhibited enhanced rate capability, and it delivered a high capacity of 87.2 mAh g −1 at 10 C. Ex -situ XRD proved that the PBM@PBN undergoes a reversible structural change (monoclinic ↔ cubic/tetragonal) during the whole cycle. PBN coating inhibited the PBM from suffering serious Mn ions dissolution during Na + insertion/extraction, thus ensured the framework stability of PBM during long-term cycling and contributed to the excellent electrochemical performance. The simple preparation of PBM@PBN makes it accessible for large-scale applications.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2024
·
IF 7.7
Mei An,Xiaoxiang Cheng,Xinsheng Luo,Tao Yang,Xianpeng Sun,Jingtao Xu,Dao Xiao,Daoji Wu,Heng Liang
Ultrafiltration (UF) is a highly efficient technique for algal-rich water purification, but it is heavily contaminated due to the complex water characteristics. To solve this problem, potassium permanganate (KMnO 4 ) oxidation enhanced with sodium sulfite (Na 2 SO 3 ) was proposed as a pretreatment means. The results showed that the end-normalized flux was elevated from 0.10 to 0.91, and the reversible fouling resistance was reduced by 99.95%. The membrane fouling mechanism also changed obviously, without the generation of cake filtration. Regarding the properties of algal-rich water, the zeta potential was decreased from −29.50 to −5.87 mV after KMnO 4 /Na 2 SO 3 pretreatment, suggesting that the electrostatic repulsion was significantly reduced. Meanwhile, the fluorescent components in algal-rich water were significantly eliminated, and the removal of dissolved organic carbon was increased to 67.46%. In the KMnO 4 /Na 2 SO 3 process, reactive manganese species (i.e., Mn(V), Mn(III) and MnO 2 ) and reactive oxygen species (i.e., SO 4 •− and • OH) played major roles in purifying algal-rich water. Specifically, SO 4 •− , • OH, Mn(V) and Mn(III) could effectively oxidize algal pollutants. Simultaneously, the in-situ adsorption and coagulation of MnO 2 could accelerate the formation of flocs by decreasing the electrostatic repulsion between cells, and protect the algal cells from being excessive oxidized. Overall, the KMnO 4 /Na 2 SO 3 process showed significant potential for membrane fouling alleviation in purifying algal-rich water.
研究领域:
环境科学
·
水处理工程
✓ 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）