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Simultaneous determination of brominated phenols in soils

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Journal of environmental Sciences 2013年第11期25卷 2306-2312页

作者： Wei Han Sen Wang Honglin Huang lei luo shuzhen zhang state key laboratory of environmental chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Brominated phenols （BPs）, a widely used group of emerging flame retardants, are important environmental contaminants and exhibit endocrine disrupting potential. Method for simultaneous determination of tetrabromobisphenol A （TBBPA）, tribromophenol （TBP）, dibromophenols （DBPs） and monobromophenols （MBPs） in soils using gas chromatography-mass spectrometry analysis （GC/MS） was successfully developed. Cleanup methods for soil extracts including several solid-phase extraction cartridges and different elution solvents were compared and optimized. Florisil cartridge with dichloromethane as the elution reagent was selected for sample cleanup owing to its high and reproducible recoveries of the target analytes in soils. Derivatization conditions were tested and the optimal conditions were obtained with 20 μL silylation reagent at room temperature. The chromatographic separation was optimized with different columns and DB-XLB column was selected for its excellent separation of the analytes. The limits of detection for the target compounds were from 0.04 to 0.19 ng/g. Mean recoveries of the compounds from spiked soils exceeded 84% with a good reproducibility, excepting that the recovery of 2-bromophenol was relatively poor （lower than 55%） due to its instability. The developed method was applied to the determination of the BPs in the soils collected from e-waste sites. The contents of BPs in the soils were at ng/g levels with TBBPA and TBP the most frequently detected. To our knowledge, this is the first report for the simultaneous determination of TBBPA, TBP, DBPs and MBPs in soils.

关键词： brominated phenols analysis soil derivatization GC/MS

Selected dark sides of biomass-derived biochars as environmental amendments

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Journal of environmental Sciences 2017年第4期29卷 13-20页

作者： Zien Chen lei luo Diyi Xiao Jitao Lv Bei Wen Yibing Ma shuzhen zhang state key laboratory of environmental chemistry and ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of Sciences Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences

With the rapid increase in the application of biochars as amendments, studies are needed to clarify the possible environmental risks derived from biochars to use safely the biomass resources. This work reported selected dark sides of maize straw-and swine manurederived biochars pyrolyzed at 300 and 500°C. During the pyrolysis processes, total heavy metals in the biochars were enriched greatly accompanying with considerable emission of the heavy metals into atmosphere and the trends became increasingly obvious with pyrolysis temperature. Meanwhile, the biochars showed distinctly decreased available heavy metals compared with raw feedstocks, which could be mainly attributed to the sorption by the inorganics in the biochars. The water-and acid-washing treatments significantly increased the releasing risks of heavy metals from biochars into the environments. Electron paramagnetic resonance analysis indicated that persistent free radicals, emerged strongly in the biochars as a function of the aromatization of biomass feedstocks, were free from the influence of water-, acid-, or organic-washing of the biochars and could remain stable even after aged in soils for 30 days. Dissolved biochars, highly produced during pyrolysis processes, showed distinct properties including lower molecular weight distribution while higher aromaticity compared with soil dissolved organic *** results of this study provide important perspectives on the safe usage of biochars as agricultural/environmental amendments.

关键词： Biochar Swine manure Heavy metal Free radical Dissolved biochar

双酚S在两种典型地带性土壤中的吸附/解吸行为研究

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环境科学学报 2020年第4期40卷 1452-1459页

作者：黄晓妍裴志国罗磊张爱佳刘彦霞秦菲可欣张庆华沈阳航空航天大学能源与环境学院沈阳110136 中国科学院生态环境研究中心环境化学与生态毒理学国家重点实验室北京100085 北京联合大学生物化学工程学院北京100023

采用批平衡实验方法研究了双酚S(BPS)在两种典型地带性土壤中的吸附/解吸行为.结果表明,吸附动力学曲线符合拟二级动力学方程.吸附等温线呈非线性,且同时符合Freundlich和Langmuir方程.相比而言,BPS更易吸附在高有机质含量的黑土中,298 ... 详细信息

采用批平衡实验方法研究了双酚S(BPS)在两种典型地带性土壤中的吸附/解吸行为.结果表明,吸附动力学曲线符合拟二级动力学方程.吸附等温线呈非线性,且同时符合Freundlich和Langmuir方程.相比而言,BPS更易吸附在高有机质含量的黑土中,298 K反应温度下BPS在黑土和红壤上的最大吸附容量分别为497.8和156.6 mg·kg^-1.吸附到两种土壤中的BPS存在解吸滞后现象,这可能是由于BPS以化学吸附和微孔扩散的形式存在于土壤中的缘故.溶液pH与BPS在土壤中的吸附容量呈负相关关系,即中性形态的BPS比阴离子形态的BPS具有更高的吸附容量.与结构类似物双酚A(BPA)的吸附相比,BPS在土壤中的吸附量更低,因此具有更高的迁移能力,可能会引起更高的环境健康风险.本研究结果为了解BPS在土壤中的迁移规律提供了数据支持.

关键词：双酚S 土壤吸附动力学吸附解吸