Effect of FeS Colloids on Desorption of As(Ⅴ) Adsorbed on Ferric Iron
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摘要: 地下水中的含铁胶体颗粒会携带污染物如砷等运移，但人们对该过程中的机理缺乏认识.通过群组静态吸附解吸模拟实验, 探究FeS胶体对吸附在覆Fe2O3石英砂上As(Ⅴ)的解吸作用, 以及腐殖酸(HA)、H2PO4-和HCO3-对解吸的影响.实验结果表明，室内合成的FeS胶体具有纳米级粒径和较大的比表面积，且能均匀稳定存在于水溶液中.低浓度的FeS胶体主要通过竞争覆Fe2O3石英砂表面的吸附点位将As(Ⅴ)解吸，而高浓度的FeS胶体主要通过与覆Fe2O3石英砂竞争对As(Ⅴ)的吸附而导致解吸.HA、H2PO4-和HCO3-对As(Ⅴ)的竞争解吸作用降低了FeS胶体导致的解吸效率.Abstract: The iron colloids in groundwater are associated with contaminants such as arsenate in transport processes, but the mechanism underlying the process is not clear. In this study, batch static adsorption and desorption experiments were conducted to investigate the effect of FeS colloids on desorption of As(Ⅴ) adsorbed on Fe2O3-coated sand, as well as the influences of HA, H2PO4- and HCO3- on the desorption. Results show that FeS colloids at low concentrations desorbed As (V) mainly by competing adsorption sites on the surface of Fe2O3-sand, while desorption at high concentrations is mainly due to the competitive adsorption for As (V) with Fe2O3-sand. As HA (humic acid), H2PO4- and HCO3- could desorb As (V) from Fe2O3-sand, As (V) desorption by FeS colloids was reduced. The results may better our understanding of the mechanisms of the arsenate release from sediments into groundwater.
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Key words:
- FeS colloids /
- sediment /
- As(Ⅴ) /
- groundwater
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图 1 FeS胶体对水溶液中As(Ⅴ)的吸附时间曲线
Fig. 1. Time profiles of As (V) adsorption by FeS colloids in aqueous solution
图 2 FeS胶体对As(Ⅴ)的解吸时间曲线(a)，以及溶液中FeS浓度随时间的变化(b)
Fig. 2. Time profiles of As(Ⅴ) desorption by FeS colloids (a), the change of FeS concentration by time in the solution (b)
图 4 不同浓度H2PO4-对FeS胶体解吸As(Ⅴ)的影响(a)，以及对溶液中H2PO4-浓度的变化(b)
Fig. 4. Effects of H2PO4- on As (V) desorption by FeS colloids (a), and the change of H2PO4- concentration in the solution (b)
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[1] Acharyya, S.K., Chakraborty, P., Lahiri, S., et al., 1999.Arsenic Poisoning in the Ganges Delta.Nature, 401(6753):545-545.doi: 10.1038/44052 [2] Anawar, H.M., Akai, J., Sakugawa, H., 2004.Mobilization of Arsenic from Subsurface Sediments by Effect of Bicarbonate Ions in Groundwater.Chemosphere, 54(6):753-762.doi: 10.1016/j.chemosphere.2003.08.030 [3] Appelo, C.A.J., Postma, D., 2005.Geochemistry, Groundwater and Pollution.CRC Press, New York. [4] Bauer, M., Blodau, C., 2006.Mobilization of Arsenic by Dissolved Organic Matter from Iron Oxides, Soils and Sediments.Science of the Total Environment, 354 (2-3):179-190.doi: 10.1016/j.scitotenv.2005.01.027 [5] Butler, E.C., Hayes, K.F., 1998.Effects of Solution Composition and pH on the Reductive Dechlorination of Hexachloroethane by Iron Sulfide.Environmental Science & Technology, 32(9):1276-1284.doi: 10.1021/es9706864 [6] Dong, H.R., Guan, X.H., Lo, I.M.C., 2012.Fate of As(Ⅴ)-Treated Nano Zero-Valent Iron:Determination of Arsenic Desorption Potential under Varying Environmental Conditions by Phosphate Extraction.Water Research, 46(13):4071-4080. doi: 10.1016/j.watres.2012.05.015 [7] Farquhar, M.L., Charnock, J.M., Livens, F.R., et al., 2002.Mechanisms of Arsenic Uptake from Aqueous Solution by Interaction with Goethite, Lepidocrocite, Mackinawite, and Pyrite:An X-Ray Absorption Spectroscopy Study.Environmental Science & Technology, 36(8):1757-1762.doi: 10.1021/es010216g [8] Fendorf, S., Michael, H.A., van Geen, A., 2010.Spatial and Temporal Variations of Groundwater Arsenic in South and Southeast Asia.Science, 328(5982):1123-1127.doi: 10.1126/science.1172974 [9] Huang, Y.X., Yang, J.K., Keller, A.A., 2014.Removal of Arsenic and Phosphate from Aqueous Solution by Metal (Hydr-) Oxide Coated Sand.ACS Sustainable Chemistry & Engineering, 2(5):1128-1138 doi: 10.1021/sc400484s [10] Huang, S.B., Wang, Y.X., Liu, C.R., et al., 2013.Hydrochemical and Fluorescent Spectroscopic Evidences of Arsenic Mobilization in Groundwater.Earth Science, 38(5):1091-1098 (in Chinese with English abstract). https://www.researchgate.net/publication/279567256_Hydrochemical_and_fluorescent_spectroscopic_evidences_of_arsenic_mobilization_in_groundwater [11] Huang, Y.Y., Liu, D.D., Li, G.R., 2012.Adsorption Kinetics of As(Ⅲ) from Groundwater by Nanoscale Zero-Valent Iron.Earth Science, 37(2):294-300 (in Chinese with English abstract). https://www.researchgate.net/profile/Sushil_Kanel2/publication/7949207_Removal_of_ArsenicIII_from_Groundwater_by_Nanoscale_Zero-Valent_Iron/links/0deec52390d55a4465000000.pdf?origin=publication_detail [12] Jeong, H.Y., Lee, J.H., Hayes, K.F., 2008.Characterization of Synthetic Nanocrystalline Mackinawite:Crystal Structure, Particle Size, and Specific Surface Area.Geochimica et Cosmochimica Acta, 72(2):493-505. doi: 10.1016/j.gca.2007.11.008 [13] Komadel, P., Stucki, J.W., 1988.Quantitative Assay of Minerals for Fe2+ and Fe3+ Using 1, 10-Phenanthroline:Ⅲ.A Rapid Photochemical Method.Clays and Clay Minerals, 36(4):379-381.doi: 10.1346/ccmn.1988.0360415 [14] Li, M.D., Zhou, L., Wang, Y.X., et al., 2014.Molybdenum Isotope Geochemistry of Arsenic Mobilization in Groundwater System.Earth Science, 39(1):99-107 (in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-DQKX201401011.htm [15] Neubauer, E., von der Kammer, F., Knorr, K.H., et al., 2013.Colloid-Associated Export of Arsenic in Stream Water during Stormflow Events.Chemical Geology, 352:81-91.doi: 10.1016/j.chemgeo.2013.05.017 [16] Nickson, R., McArthur, J., Burgess, W., et al., 1998.Arsenic Poisoning of Bangladesh Groundwater.Nature, 395(6700):338-338.doi: 10.1038/26387 [17] Saalfield, S.L., Bostick, B.C., 2010.Synergistic Effect of Calcium and Bicarbonate in Enhancing Arsenate Release from Ferrihydrite.Geochimica et Cosmochimica Acta, 74(18):5171-5186. doi: 10.1016/j.gca.2010.05.022 [18] Sherman, D.M., Randall, S.R., 2003.Surface Complexation of Arsenic(V) to Iron(Ⅲ) (Hydr)Oxides:Structural Mechanism from Ab Initio Molecular Geometries and EXAFS Spectroscopy.Geochimica et Cosmochimica Acta, 67(22):4223-4230.doi: 10.1016/S0016-7037(03)00237-0 [19] Smedley, P.L., Kinniburgh, D.G., 2002.A Review of the Source, Behaviour and Distribution of Arsenic in Natural Waters.Applied Geochemistry, 17(5):517-568.doi: 10.1016/s0883-2927(02)00018-5 [20] State Environmental Protection Agency, 2002.Water and Wastewater Monitoring Analysis Method.China Environmental Science Press, Beijing, 216-219 (in Chinese). [21] Tadanier, C.J., Schreiber, M.E., Roller, J.W., 2005.Arsenic Mobilization through Microbially Mediated Deflocculation of Ferrihydrite.Environmental Science & Technology, 39(9):3061-3068.doi: 10.1021/es048206d [22] Wang, S.L., Mulligan, C.N., 2006.Effect of Natural Organic Matter on Arsenic Release from Soils and Sediments into Groundwater.Environmental Geochemistry and Health, 28(3):197-214.doi: 10.1007/s10653-005-9032-y [23] Wasserman, G.A., Liu, X.H., Parvez, F., et al., 2004.Water Arsenic Exposure and Children's Intellectual Function in Araihazar, Bangladesh.Environmental Health Perspectives, 112(13):1329-1333. doi: 10.1289/ehp.6964 [24] Wolthers, M., Charlet, L., van der Weijden, C.H., et al., 2005.Arsenic Mobility in the Ambient Sulfidic Environment:Sorption of Arsenic(V) and Arsenic(Ⅲ) Onto Disordered Mackinawite.Geochimica et Cosmochimica Acta, 69(14):3483-3492. doi: 10.1016/j.gca.2005.03.003 [25] 黄爽兵, 王焰新, 刘昌蓉, 等, 2013.含水层中砷活化迁移的水化学与DOM三维荧光证据.地球科学, 38(5):1091-1098. http://www.earth-science.net/WebPage/Article.aspx?id=2774 [26] 黄园英, 刘丹丹, 李桂荣, 2012.纳米铁对地下水中As(Ⅲ)的吸附动力学.地球科学, 37(2) :294-300. http://www.earth-science.net/WebPage/Article.aspx?id=2229 [27] 李梦娣, 周炼, 王焰新, 等, 2014.地下水系统中砷活化的钼同位素地球化学指示.地球科学, 39(1):99-107. http://www.earth-science.net/WebPage/Article.aspx?id=2833 [28] 国家环境保护总局, 2002.水和废水监测分析方法.北京:中国环境出版社, 216-219. -
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