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Phylogenetic analysis and arsenate reduction effect of the arsenic-reducing bacteria enriched from contaminated soils at an abandoned smelter site

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Journal of Environmental Sciences 2008年第12期20卷 1501-1507页

作者： ZHANG, Xuexia jia, yongfeng WANG, Xin XU, Liying Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate University Chinese Academy of Sciences Beijing 100039 China

Microbial reduction of As(V)(i.e.,arsenate)plays an important role in arsenic(As)mobilization in aqueous *** this study,we investigated As(V)reduction characteristics of the bacteria enriched from the arsenic-contaminated soil at an abandoned smelter *** was found that As(V)was completely reduced to As(III)(i.e.,arsenite)in 21 *** 3-d incubation,a yellow solid was precipitated and the concentration of As(III)decreased *** 150 h incubation,ca.65%of soluble arsenic was removed fro...

关键词： microbial reduction arsenic phylogenetic analysis

Bioaccumulation of cadmium bound to humic acid by the bivalve Meretrix meretirx Linnaeus from solute and particulate pathways

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Journal of Environmental Sciences 2010年第2期22卷 198-203页

作者： Xing Wu yongfeng jia Huijie Zhu He Wang Key Laboratory of Pollution Ecology and Environmental Engineering lnstimte of Applied Ecology Chinese Academy of Sciences Shengyang 110016 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

Humic acid is an important pool of heavy metals in sediments. Generally, the presence of refractory humic matter in aquatic systems would decrease the bioavailability of Cd and hence control the bioaccumulation of Cd in benthic animals. In the present work, we applied a suspending system to determine the relative importance of particulate and dissolved fractions of humic acid as Cd sources for the bivalve Meretrix meretrix and to investigate the difference of bioaccumulation characteristics of Cd adsorbed on different fractions of humic acid. The results showed *** bioaccumulation characteristics of Cd from particulate and dissolved fractions of humic acid were apparently different due to biological responses of the clam to the particulates. At Cd concentration of 140 mg/kg, the accumulation of Cd from Cd associated with humic acid mixtures was mainly attributed to the dissolved fractions of humic acid. Compared to particulate fractions, Cd associated with the dissolved fractions of humic acid may be more bioavailable.

关键词： humic acid bioaccumulation cadmium Meretrix meretrix Linnaeus

Effects of pore size and dissolved organic matters on diffusion of arsenate in aqueous solution

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Journal of Environmental Sciences 2017年第2期29卷 190-196页

作者： Yulong Wang Shaofeng Wang Xin Wang yongfeng jia Key Laboratory of Pollution Ecology and Environmental Engineering Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China

Presented here is the influence of membrane pore size and dissolved organic matters on the diffusion coefficient（D） of aqueous arsenate, investigated by the diffusion cell method for the first time. The p H-dependent diffusion coefficient of arsenate was determined and compared with values from previous studies; the coefficient was found to decrease with increasing p H, showing the validity of our novel diffusion cell method. The D value increased dramatically as a function of membrane pore size at small pore sizes, and then increased slowly at pore sizes larger than 2.0 μm. Using the Exp Assoc model, the maximum D value was determined to be 11.2565 × 10^-6cm^2/sec. The presence of dissolved organic matters led to a dramatic increase of the D of arsenate, which could be attributed to electrostatic effects and ionic effects of salts. These results improve the understanding of the diffusion behavior of arsenate, especially the important role of various environmental parameters in the study and prediction of the migration of arsenate in aquatic water systems.

关键词： Arsenate Diffusion Pore p H Dissolved organic matters Migration

Bacterial reduction and release of adsorbed arsenate on Fe(III)-, Al- and coprecipitated Fe(III)/Al-hydroxides

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Journal of Environmental Sciences 2012年第3期24卷 440-448页

作者： Xuexia Zhang yongfeng jia Shaofeng Wang Rongrong Pan Xudong Zhang Key Laboratory of Pollution Ecology and Environmental Science Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Guangdong Institute of Eco-Environment and Soil Sciences Guangzhou 510650China

Mobilization of arsenic under anaerobic conditions is of great concern in arsenic contaminated soils and sediments. Bacterial reduction of As（V） and Fe（III） influences the cycling and partitioning of arsenic between solid and aqueous phase. We investigated the impact of bacterially mediated reductions of Fe（III）/Al hydroxides-bound arsenic（V） and iron（III） oxides on arsenic release. Our results suggested that As（V） reduction occurred prior to Fe（III） reduction, and Fe（III） reduction did not enhance the release of arsenic. Instead, Fe（III） hydroxides retained their dissolved concentrations during the experimental process, even though the new iron mineral-magnetite formed. In contrast, the release of reduced As（III） was promoted greatly when aluminum hydroxides was incorporated. Thus, the substitution of aluminum hydroxides may be responsible for the release of arsenic in the contaminated soils and sediments, since aluminum substitution of Fe（III） hydroxides universally occurs under natural conditions.

关键词： arsenic aluminium hydroxides ferric hydroxides bacterial reduction

The long-term stability of calcium arsenates:Implications for phase transformation and arsenic mobilization

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Journal of Environmental Sciences 2019年第10期31卷 29-41页

作者： Danni Zhang Shaofeng Wang Ying Wang Mario A.Gomez yongfeng jia Key Laboratory of Pollution Ecology and Environmental Engineering Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Institute of Environmental Protection Shenyang University of Chemical Technology Shenyang 110142 China

It is well known that calcium arsenates may not be a good choice for arsenic removal and immobilization in hydrometallurgical ***,they are still produced at some plants in the world due to various ***,calcium arsenates can also naturally precipitate under some specific ***,the transformation process of poorly crystalline calcium arsenates(PCCA)and the stability of these samples under atmospheric CO2 are not yet well *** work investigated the transformation process of PCCA produced by using different neutralization reagents(CaO ***)with various Ca/As molar ratios at pH 7-12 in the presence of atmospheric *** aging at room temperature for a period of time,for samples neutralized with NaOH and precipitated at pH 10 and 12,release of arsenic back into the liquid phase *** contrast,for the samples precipitated at pH 8,the aqueous concentration of arsenic was observed to ***,Raman,and SEM results suggested that the formation of various types of crystalline calcium carbonates and/or calcium arsenates controls the arsenic ***,the application of lime may enhance the stability of the generated ***,no matter what neutralization reagent is used,the stability of the generated PCCA is still of concern.

关键词： Arsenic Precipitate Calcium Stability CO2

Simultaneous removal and oxidation of arsenic from water byδ-MnO 2 modified activated carbon

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Journal of Environmental Sciences 2020年第8期32卷 147-160页

作者： Yulong Wang Hupeng Liu Shaofeng Wang Xuhui Li Xin Wang yongfeng jia Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions College of Environment and PlanningHenan UniversityKaifeng 475004China Key Laboratory of Pollution Ecology and Environmental Engineering Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China National Demonstration Center for Environmental and Planning Henan UniversityKaifeng 475004China

The ubiquitous arsenic in groundwater poses a great risk to human health due to its environmental toxicity and *** the present work,a new adsorbent,δ-MnO2 modified activated carbon,was prepared,and its performance for the uptake of arsenate and arsenite species from aqueous solutions was investigated by batch *** techniques,including FESEM-EDX,p-XRD,XPS and BET surface area analysis,were employed to characterize the properties of the adsorbent and the arsenic adsorption *** results showed thatδ-MnO2 covered on the surface and padded in the pores of the activated *** kinetic studies revealed that approximately 90.1%and 76.8%of As(Ⅲ)and As(V),respectively,were removed by the adsorbent in the first 9 hr,and adsorption achieved equilibrium within 48 *** maximum adsorption capacities of As(V)and As(Ⅲ)at pH 4.0 calculated from Langmuir adsorption isotherms were 13.30 and 12.56 mg/g,*** effect of pH on As(Ⅴ)and As(Ⅲ)removal was similar,and the removal efficiency significantly reduced with the increase of solution *** oxidation and adsorption kinetics showed that the As(Ⅴ)concentration in solution due to As(Ⅲ)oxidation and reductive dissolution of MnO2 increased rapidly during the first 12 min,and then gradually *** on the XPS analysis,nearly 93.3%of As(Ⅲ)had been oxidized to As(V)on the adsorbent surface and around 38.9%of Mn(Ⅳ)had been reduced to Mn(Ⅱ)after As(Ⅲ)*** approach provides a possible method for the purification of arsenic-contaminated groundwater.

关键词： δ-MnO 2 modified activated carbon Arsenate Arsenite Adsorption Oxidation

Characterization of Fe5(AsO3)3Cl2(OH)4·5H2O,a new ferric arsenite hydroxychloride precipitated from FeCl3-As2O3-HCl solutions relevant to arsenic immobilization

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Journal of Environmental Sciences 2020年第4期32卷 205-215页

作者： Zidan Yuan Xu Ma Xing Wu Guoqing Zhang Xin Wang Shaofeng Wang yongfeng jia Key Laboratory of Pollution Ecology and Environmental Engineering Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China

Tooeleite(Fe6(As03)4 SO4(OH)4·4 H2 O)is widely precipitated for direct As(III)removal from sulfate-rich industrial ***,whether or not Fe(III)-As(III)-Cl(-I)precipitate is produced in chloridizing leaching media for As immobilization is almost *** work founded the existence of ferric arsenite(hydroxy)chloride as a new mineral for As(III)*** chemical composition and solid characterization were subsequently studied by using scanning electron microscope with an energy dispersive spectrometer(SEM-EDS),X-ray diffraction(XRD),infrared(FT-IR),Raman spectroscopy and thermogravimetric(TG)*** results showed the formation of a yellow precipitate after 3-days reaction of Fe(III)/As(III)with molar ratio≈1.7 in chloride solution at pH 2.3 neutralized with *** with tooeleite,chemical analysis and solid characterization indicated that Cl(-I)replaces S04(-II)producing ferric arsenite hydroxychloride with formula Fe5(As03)3-Cl2(OH)4·5 H2 *** new plate shaped solid showed better crytallinity than tooeleite,although it has similar morphology and characteristic bands to *** FT-IR bands at 628,964 cm-1 and the Raman bands at 448,610,961 cm-1 were assigned to Fe-O or As(Ⅲ)-O-Fe or As(Ⅲ)-O bending/stretching vibration,indicating that both arsenite and chloride substituted for the position of sulfate for ferric arsenite hydro xychloride produced due to the lack of the ***-(I)also contributed to increase As removal efficiency in aqueous sulfate media under acidic pH conditions via the probable formation of sulfatechloride ferric arsenite.

关键词： Chloride ion Acidic pH Ferric arsenite hydroxychloride Characterization Immobilization

Enhanced removal of high-As(Ⅲ)from Cl(-Ⅰ)-diluted SO_(4)(-Ⅱ)-rich wastewater at pH 2.3 via mixed tooeleite and(Cl(-Ⅰ)-free)ferric arsenite hydroxychloride formation

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Journal of Environmental Sciences 2023年第2期124卷 31-41页

作者： Zidan Yuan Guoqing Zhang Xing Wu Xu Ma Jinru Lin Shaofeng Wang yongfeng jia Key Laboratory of Pollution Ecology and Environmental Engineering Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control Ministry of EducationHenan Key Laboratory for Environmental Pollution ControlSchool of EnvironmentHenan Normal UniversityHenan 453007China Key Laboratory of Industrial Ecology and Environmental Engineering(Ministry of Education China)School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China

An advanced cost-saving method of removal of high-As(Ⅲ)from SO_(4)(-Ⅱ)-rich metallurgical wastewater has been developed by diluting the SO_(4)(-Ⅱ)content with As(Ⅲ)-Cl(-Ⅰ)-rich metallurgical wastewater and then by the direct precipitation of As(Ⅲ)with Fe(Ⅲ)at pH ***(Ⅲ)removal at various SO_(4)(-Ⅱ)/Cl(-Ⅰ)molar ratios and temperatures was *** results showed that 65.2–98.2%of As(Ⅲ)immobilization into solids occurred at the SO_(4)(-Ⅱ)/Cl(-I)molar ratios of 1:1–32 and 15–60℃in 3 days,which were far higher than those in aqueous sole SO4(-Ⅱ)or Cl(-Ⅰ)media at the equimolar SO_(4)(-Ⅱ)or Cl(-Ⅰ)and the same ***_(4)(-Ⅱ)/Cl(-Ⅰ)molar ratio of 1:4 and 25℃were optimal conditions to reach the As removal *** aqueous SO4(-Ⅱ)and Cl(-Ⅰ)played a synergetic role in the main tooeleite formation together with(Cl(-Ⅰ)-free)ferric arsenite hydroxychloride(FAHC)involving the substitution of AsO_(3)^(3−)for Cl(-Ⅰ)for enhanced As *** competitive complexation among FeH_(2)AsO_(3)^(2+),FeSO_(4)^(+)and FeCl^(2+)complexes was the main mechanism for the maximum As(Ⅲ)precipitation at the SO4(-Ⅱ)/Cl(-I)molar ratio of 1:*** As(Ⅲ)immobilization at high temperature with increased Fe(Ⅲ)hydrolysis was due to the formation of As(Ⅲ)-bearing ferrihydrite with the relatively high Fe/As molar ratio at acidic pH.

关键词： High-As(III) Sulfate Chlorine ion Removal Complex

Spatial and temporal evolutions of groundwater arsenic approximately along the flow path in the Hetao basin, Inner Mongolia

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Chinese Science Bulletin 2013年第25期58卷 3070-3079页

作者： GUO HuaMing ZHANG Yang jia yongfeng ZHAO Kai KIM Kangjoo State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences School of Water Resources and Environment China University of Geosciences Department of Environmental Engineering Kunsan National University

Patchy distribution of high As groundwater has normally been observed in As-affected areas. Spatial and temporal evolutions help in better understanding mechanisms of As mobilization and in developing effective strategies for ensuring drinking water safety. Four multilevel samplers were installed approximately along the groundwater flow path to investigate spatial and temporal variations in groundwater As in the Hetao basin, Inner Mongolia. Both water chemistry and groundwater level were monitored for about two years. Groundwater As concentration generally showed increasing trends, and Eh values showed decreasing trends along the flow path, indicating that As was mobilized via reductive dissolution of Fe oxides. However, in evaporation discharge area, shallow groundwater As was generally lower than those upstream and downstream. In addition to evaporation, siderite and pyrite precipitations controlled groundwater As concentrations. The negative correlations between As concentration and SIpyrite (or SIsiderite) implied that siderite and pyrite precipitations wold scavenge groundwater As and lower As concentration. Temporal variation showed different trends in different locations. It may reflect replenishment of high/low As groundwater for the increase/decrease in As concentrations, resulting from water level fluctuation. The increase trends in groundwater As concentrations at depth around 15m in the discharge areas would result from the increase in the recharge of underlying groundwater (20m) with high As concentration due to enhanced evaporation in the seasons with high water levels. The investigation suggested that monitoring of groundwater As should be routinely carried out to ensure the drinking water safety in the As-affected areas.

关键词：地下水流流动路径河套盆地内蒙古高砷时间演化空间