Impact of ionic strength on goethite colloids co-transported with arsenite (As 3+ ) through a saturated sand column under anoxic condition: Experiment and mathematical modeling.

Autor: Boonkaewwan S; International Postgraduate Programs in Environmental Management, Graduate School, Chulalongkorn University, Bangkok, 10330, Thailand; Center of Excellence on Hazardous Substance Management (HSM), Chulalongkorn University, Bangkok, 10330, Thailand. Electronic address: minkbkw@gmail.com., Chotpantarat S; Department of Geology, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand; Center of Excellence in Environmental Innovation and Management of Metals (EnvIMM), Environmental Research Institute, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok, 10330, Thailand. Electronic address: Srilert.C@chula.ac.th.
Jazyk: angličtina
Zdroj: Environmental research [Environ Res] 2024 Nov 01; Vol. 260, pp. 119660. Date of Electronic Publication: 2024 Jul 22.
DOI: 10.1016/j.envres.2024.119660
Abstrakt: The knowledge about co-transport of goethite and As 3+ to investigate the effect of goethite colloids on As 3+ transport under various degrees of seawater intrusion, particular extremely conditions, in groundwater environment is still limited. The main objective is to investigate the influence of seawater intrusion on the sorption, migration, and reaction of As 3+ and goethite colloids into sand aquifer media under anoxic conditions by using the bench-scale and reactive geochemical modeling. The research consisted of two parts as follows: 1) column transport experiments consisting of 8 columns, which were packed by using synthesis groundwater at IS of 0.5, 50, 200, and 400 mM referring to the saline of seawater system in the study area, and 2) reactive transport modeling, the mathematical model (HYDRUS-1D) was applied to describe the co-transport of As 3+ and goethite. Finally, to explain the interaction of goethite and As 3+ , the Derjaguin-Landau-Verwey-Overbeek (DLVO) calculation was considered to support the experimental results and HYDRUS-1D model. The results of column experiments showed goethite colloids can significantly inhibit the mobility of As 3+ under high IS conditions (>200 mM). The R f of As 3+ bound to goethite grows to higher sizes (47.5 and 65.0 μm for 200 and 400 mM, respectively) of goethite colloid, inhibiting As 3+ migration through the sand columns. In contrast, based on R f value, goethite colloids transport As 3+ more rapidly than a solution with a lower IS (0.5 and 50 mM). The knowledge gained from this study would help to better understand the mechanisms of As 3+ contamination in urbanized coastal groundwater aquifers and to assess the transport of As 3+ in groundwater, which is useful for groundwater management, including the optimum pumping rate and long-term monitoring of groundwater quality.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024 Elsevier Inc. All rights reserved.)
Databáze: MEDLINE
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