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Activation of Persulfate by Magnetic MnFe2O4-bentonite for Catalytic Degradation of 2,4-Dichlorophenol in Aqueous Solutions

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Chemical Research in Chinese Universities 2017年第3期33卷 415-421页

作者： ZHAO Yongsheng LI Qin REN Hejun ZHOU Rui Key Laboratory of Groundwater resources and environment Ministry of Education College of Environment and Resources Jihn University Changehun 130021 P. R. China

Magnetic MnFe2O4-bentonite was synthesized by chemical co-precipitation method（CCM） and applied as catalyst in heterogeneous activation of persulfate（PS） to oxidize a target pollutant, 2,4-dichlorophenol（2,4-DCP）, in aqueous solutions. The surface morphology and structure of MnFe2On-bentonite were characterized by X-ray diffraction（XRD）, scanning electron microscope（SEM）, energy dispersive X-ray（EDX） and X-ray photoelectron spectroscopy（XPS） *** catalytic activity of MnFe2O4-bentonite for 2,4-DCP degradation was evaluated considering the effects of various process parameters, such as mass ratio of MnFe2O4 to bentonite, concentration of catalyst, PS concentration, and pH. The MnFe2O4-bentonite hybrid exhibited higher catalytic activity than pure MnFe2O4. Treatment with 5 g/L MnFe2O4-bentonite at 30℃ for 240 rain oxidized 92% of 100 mg/L 2,4-DCP（70.2% mineralization）, whereas treatment with pure MnFe2O4 under the same condition oxidized only 70% of the pollutant. This result indicate the erdlanced performance of the activated PS. Moreover, MnFe2O4-bentonite exhibits stable performance with minimal loss in activity after five successive runs. Thus, MnFe2O4-bentonite could be a promising catalyst in oxidative degradation of 2,4-DCE

关键词： 2,4-Dichlorophenol Advanced oxidation process Heterogeneous reaction MnFe2O4-bentonite Sulfate radical

Geochemical Characteristics and Occurrence States of RE Element in Phosphorite in Xinhua , Zhijin, Guizhou

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Journal of Rare Earths 2004年第z1期22卷 320-324页

作者： Zhang Jie Zhang Qin Chen Dailiang Cheng Jiyan Zhu Lei Chengdu University of Technology Geosciences College Chengdu 610059 China Guizhou University College of Resources and Environment Guiyang 550003 China Guizhou University College of Resources and Environment Guiyang 550003 China GuiZhou Geological Survey Academy Ministry of Chemical Industry Zunyi 563100 China Guizhou University College of Resources and Environment Guiyang 550003 China Guizhou University College of Resources and Environment Guiyang 550003 China

The RE and composition of trace elements analysis show that phosphorite-ores are rich in ∑ RE concentration generally in Xinhua, *** phosphorites were measured to gather LRE and HRE *** is higher than other *** phosphorite has enriched Y, La and Nd chemical *** are leading characteristics of concentrated La, LRE and Y, *** chondrite-normalized RE element patterns of the Xinhua dolomitic phosphorite distribute mode for rightwards type to one side of the ***/HRE ＞ 1, (La/Sm)N ＞ (Gd/Yb)N, and all indicate that LRE content is higher than *** test mode of chemical analysis of single mineral, chemistry phase analysis, scan electric analysis and micro-electronics probe analysis were *** chart of EDAX showed that there was representative element-Y(RE) in *** was no independent mineral of the *** is show that part of the few rare earth chemical element is adsorbed by the clay mineral, much for the type of quality isomorphic form exist in the apatite crystal structure of phosphorite inside.

关键词： occurrence of RE phosphorites in Xinhua rare earths

Vc-Functionalized Fe3O4 Nanocomposites as Peroxidase-like Mimetics for H2O2 and Glucose Sensing

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Chemical Research in Chinese Universities 2018年第2期34卷 260-268页

作者： REN Hejun MA Taigang ZHAO Jian ZHOU Rui Key Laboratory of Groundwater resources and environment Ministry of EducationCollege of Environment and Resources Jilin University Changchun 130021 P. R. China

A simple and efficient colorimetric biosensing for hydrogen peroxide and glucose with peroxidase-like vitamin C（Vc） functionalized Fe3O4 magnetic nanoparticles（Vc/Fe3O4MNPs） as a catalyst is reported. Compared with Fe3O4 MNPs and other catalysts, Vc/Fe3O4 MNPs exhibited superior catalytic properties. Kinetic studies indicated that vitamin C incorporated on Fe3O4 MNPs improved the affinity toward H2O2. As low as 0,29 μmol/L H2O2 can be detected with a wide linear range of 0.5-100 μmol/L H2O2; moreover, as low as 0.288 μmol/L glucose can be detected with a linear range of 0.5-25 μmol/L glucose. The detection method was highly sensitive in sensing H2O2 and glucose. The robustness of Vc/Fe3O4 MNPs rendered them suitable for wide ranging applications.

关键词： Vc/Fe3O4 Colorimetric biosensing Enzyme mimetics Hydrogen peroxide Glucose

Thermodynamic Characteristics and Mechanisms of Heavy Metals Adsorbed onto Urban Soil

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Chemical Research in Chinese Universities 2013年第1期29卷 42-47页

作者： LI Yue-ming KANG Chun-li CHEN Wei-wei MING Lian ZHANG Sai GUO Ping Key Lab of Groundwater resources and environment Ministry of Education College of Environment and Resources Jilin University Changchun 130012 P. R. China

The thermodynamic characteristics of heavy metals adsorbed onto urban soil and the relative adsorption mechanisms were studied by the batch experiment. The results show that there existed dynamic adsorption-desorption equilibrium processes of cationic and anionic ions of heavy metals onto urban soil, which may have an impact on the pH of the adsorption system. The amounts of heavy metals adsorbed onto urban soil increased with the increase of the equilibrium concentration, but their adsorption amounts were not the maximum adsorption amounts. The higher the pH was, the greater the adsorption capacity of the urban soil at the same equilibrium concentration was, and the adsorption amounts of heavy metals onto urban soil followed the order of Pb〉Cu〉Cd〉Zn〉Ni. There were coordination reaction, hydrolysis reaction, exchange reaction in the adsorption processes of heavy metals onto urban soil. With the increase of pH, the influencing degree of pH on the different reactions of heavy metals in the soil increased, meanwhile the effects of other physicochemical properties of soil on the adsorption of heavy metals were weakened.

关键词： Urban soil Heavy metal Adsorption pH

Highly efficient and selective removal of low-concentration antibiotics from aqueous solution by regenerable Mg（OH）2

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Journal of environmental Sciences 2020年第1期32卷 228-237页

作者： Yongjing Wang Jingjing Lin Yonghao Wang Zemeng Liu Jinlu Lian Minghua Liu Fujian Provincial Engineering Research Center for High-value Utilization Technology of Plant resources College of Environment and ResourcesFuzhou University

The prevalent presence of fluoroquinolone antibiotics in aquatic environments has attracted considerable attention because of their harmful effects on humans and the ecological *** hydroxide nanocrystals were found to act as a simple and effective adsorbent to remove low-concentration ciprofloxacin(CIP)in aqueous *** as-prepared Mg(OH)2 nanocrystals exhibited excellent CIP adsorption performance and high selectivity toward CIP molecules compared with other antibiotics or aromatics,e.g.,norfloxacin(NOR)and eosin B(EB).The adsorbent showed pH-dependent adsorption,indicating that the adsorption process is probably dominated by an electrostatic interaction *** addition,structural analysis of the adsorbent indicated that coordination and hydrogen bonding between CIP and Mg(OH)2 nanocrystal might also be involved in the adsorption ***,the adsorbent could be easily recovered by pyrolysis and hydration without significant reduction of adsorption *** superior adsorption behavior of Mg(OH)2 nanocrystal indicates that it may serve as a potential adsorbent material candidate for the selective removal of CIP from aquatic environments.

关键词： Magnesium hydroxide nanocrystals Antibiotics Adsorption Selectivity adsorption Regenerable

A novel method to assess the effect of diagenesis on fossil teeth:Rare earth element signatures

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Journal of Rare Earths 2011年第7期29卷 710-715页

作者：文星跃王成善黄成敏柏松张擎 college of Architecture and environment Sichuan University college of resources and environmental Engineering Mianyang Normal University School of Earth Science and resources China University of Geosciences college of Chemistry and environment Protection Engineering Southwest University for Nationalities Chengdu Institute of Relics and Archaeology

An attempt was made to test the validity of the signatures of rare earth elements （REE） as a tool to judge the effect of diagenesis on fossil teeth. Sample REE contents and features of fossil teeth and sediments from Jinsha Relics, Sichuan, Southwest China were analyzed. The difference in REE content between fossil teeth is significantly greater than that between sediments at the Jinsha Relics. Chondrite-normalized REE patterns showed that obvious LREE enrichment and strong Ce and HREE depletion occurred in all fossil teeth samples. Meanwhile δCe and δEu values varied more dramatically in fossil teeth than in sediments. Accordingly, low content, LREE enrichment, strong Ce depletion, the significantly positive correlation between LREE/HREE and δCe, and unchanged （La/Yb）N demonstrated that the fossil teeth from Jinsha Relics have not been contaminated by diagenesis. The REE signature might be a potential proxy to assess the effect of diagenesis on fossil teeth.

关键词： fossil teeth sediment REE diagenesis Jinsha Relics

Distribution and enrichment patterns of selenium in the Ediacaran and early Cambrian strata in the Yangtze Gorges area, South China

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Science China Earth Sciences 2017年第7期60卷 1268-1282页

作者： TIAN XingLei LUO KunLi Institute of Geographic Sciences and Natural resources Research Chinese Academy of Sciences college of resources and environment University of the Chinese Academy of Sciences

The distribution and enrichment patterns of selenium(Se) in the E-?1 strata in the Yangtze Gorges area of South China were obtained. The geochemical characteristics of the significantly and non-significantly enriched strata of Se were *** observed enrichment factor(EF, relative to the upper continental crust) and concentration coefficient(CC, relative to the similar lithology in Eastern China) both suggest that Se is the most enriched/concentrated(SeEF=26.97, SeCC=48.04) among the analyzed23 trace elements the E-?1 strata. The normalized enrichment factor(EF′, EF after Al or Th normalized) shows Se is secondly enriched(SeEF′=218.73), which is slightly lower than cadmium(CdEF′=288.46) but significantly higher than the third enriched trace element arsenic(AsEF′=97.49). Se concentrations in the E-?1 strata vary from Yanjiahe(54.45)>Doushantuo(24.72)>Dengying(2.48)>Shipai(1.95)>lower Tianheban(1.24)Formations. Se concentrations in the E-?1 strata are best displayed on natural logarithm normal quantile-quantile(Q-Q) plots and shown as a positive-skewed distribution pattern. The Se significantly enriched(EF>10) strata sequences mainly include the lower and upper Doushantuo member II(DST-II), top DST-III, DST-IV, the basal and upper Yanjiahe Formation, and lower and upper Shuijingtuo Formation. Geochemical characteristics indicate that Se concentrations in the significantly enriched strata were generally influenced by terrigenous detrital as well as the combined action of single or multiple factors, such as hydrotherm,volcanic debris and deep source. Moreover, pyrite and organic matter promoted the enrichment of Se in the upper DST-II, DST-IV,upper Shuijingtuo Formation and lower DST-II, upper Shuijingtuo Formation, respectively. The Se concentrations in the n

关键词： Ediacaran-early Cambrian Selenium Distribution and enrichment patterns Elemental geochemistry

Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： Feng Zhang Chenyang Zhang Linlin Wu Wei Sun Hongliang Zhang Jianhua Chen Yong Pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

Solvothermal Synthesis,Crystal Structure and Photoluminescence Property of a 3D Lead(Ⅱ)Coordination Polymer Based on Terephthalic Acid

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Chinese Journal of Structural Chemistry 2016年第1期35卷 61-68页

作者：林小英杨攀陈君刘明华林诚 School of Chemical Engineering Fuzhou University college of Ecological environment and Urban Construction Fujian University of Technology college of environment and resources Fuzhou University

Solvothermal reaction of Pb（NO3）2·6H2O with rigid linear ligand terephthalic acid（H2pta） in N,N-dimethylformamide（DMF） produced a new three-dimensional（3D） lead（Ⅱ）coordination polymer[Pb2（pta）1.5（μ4-OH）（DMF）]n 1,and its structure was characterized by single-crystal X-ray diffraction *** polymer 1,the μ4-OH bridges the nearby lead（Ⅱ） ions into an infinite one-dimensional（1D） chain,and then the organic ligand pta^2- joins the neighbored chains into a 3D structure by two similar connection modes in different *** solid-state photoluminescent studies revealed that 1 exhibits a strong greenish emission mainly originating from ligand-to-metal charge transfer between the delocalized π bonds of the aromatic carboxylate ligand pta^2- and the p orbitals of the Pb^2＋ centers.

关键词： solvothermal synthesis lead(Ⅱ) coordination polymer terephthalic acid photoluminescence property crystal structure