Novel DGT method with tri-metal oxide adsorbent for in situ spatiotemporal flux measurement of fluoride in waters and sediments

WATER RESEARCH

卷:99

Article

Zhou, Chun-Yang¹  Guan, Dong-Xing¹  Williams, Paul N.²  Luo, Jun¹  Ma, Lena Q.^1,3 

[1] Nanjing Univ, Sch Environm, State Key Lab Pollut Control & Resource Reuse, Nanjing 210023, Jiangsu, Peoples R China

[2] Queens Univ Belfast, Sch Biol Sci, Inst Global Food Secur, Belfast BT9 7BL, Antrim, North Ireland

[3] Univ Florida, Soil & Water Sci Dept, Gainesville, FL 32611 USA

关键词: Fluoride;    Diffusive gradients in thin-films;    Sediment;    Surface water;   

DOI  :  10.1016/j.watres.2016.04.062

来源: Elsevier

【 摘 要 】

Natural mineral-water interface reactions drive ecosystem/global fluoride (F-) cycling. These small-scale processes prove challenging to monitoring due to mobilization being highly localized and variable; influenced by changing climate, hydrology, dissolution chemistries and pedogenosis. These release events could be captured in situ by the passive sampling technique, diffusive gradients in thin-films (DGT), providing a cost-effective and time-integrated measurement of F- mobilization. However, attempts to develop the method for F- have been unsuccessful due to the very restrictive operational ranges that most F--absorbents function within. A new hybrid-DGT technique for F- quantification containing a three-phase fine particle composite (Fe Al Ce, FAC) adsorbent was developed and evaluated. Sampler response was validated in laboratory and field deployments, passing solution chemistry QC within ionic strength and pH ranges of 0-200 mmol L-1 and 43-9.1, respectively, and exhibiting high sorption capacities (98 8 g cm-2). FAC-DGT measurements adequately predicted up to weeklong averaged in situ F- fluvial fluxes in a freshwater river and F- concentrations in a wastewater treatment flume determined by high frequency active sampling. While, millimetre-scale diffusive fluxes across the sediment-water interface were modeled for three contrasting lake bed sediments from a F--enriched lake using the new FAC-DGT platform. (C) 2016 Elsevier Ltd. All rights reserved.

【 授权许可】

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