Role of Humic Substances on Cr(VI) Removal from Groundwater with Pyrite

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Tarih

2017

Dergi Başlığı

Dergi ISSN

Cilt Başlığı

Yayıncı

Springer

Erişim Hakkı

info:eu-repo/semantics/closedAccess

Özet

Groundwater composition may have a pronounced impact on long-termperformance of permeable reactive barriers (PRBs). Here, batch and column experiments were conducted to investigate the effects of humic acid (HA) on Cr(VI) removal by pyrite in systems containing cations such as Ca2+ and Mg2+. HAwas observed to have inhibitory effect on Cr(VI) uptake by pyrite under the experimental conditions studied (e. g., pH 3 to 8). HA sorbed onto pyrite surface and thus (1) competed against Cr(VI) for pyritic surface sites and/or (2) increased electrostatic repulsion between Cr(VI) and pyrite. In systems with HA and Ca2+/Mg2+, the Cr(VI) uptake by pyrite decreased drastically relative to HA alone due to the aggregation of HA with Ca2+/Mg2+. The formation of such HA aggregates/precipitates blocked Cr(VI) ions to reach its binding sites, thereby resulting in a substantial decrease in Cr(VI) uptake. Overall, the results have major implications for proper design and operation of PRBs with pyrite as the reactive material.

Açıklama

Anahtar Kelimeler

Pyrite, Humic acid, Chromium, Permeable reactive barrier (PRB), Reduction

Kaynak

Water Air and Soil Pollution

WoS Q Değeri

Q3

Scopus Q Değeri

Q2

Cilt

228

Sayı

1

Künye