Colloid formation in groundwater by subsurface aeration: characterisation of the geo-colloids and their counterparts

A. Wolthoorn, E.J.M. Temminghoff, W.H. van Riemsdijk

Research output: Contribution to journalArticleAcademicpeer-review

19 Citations (Scopus)

Abstract

Subsurface aeration is used to oxidise Fe in situ in groundwater to make the water potable. In a groundwater system with pH > 7, subsurface aeration results in a non-mobile Fe precipitate and mobile Fe colloids. Since originally the goal of subsurface aeration is to remove Fe in situ, the formation of non-mobile Fe precipitate is the desired result. In addition to this intended effect, subsurface aeration may also strongly enhance the microbiological removal of NH4 in the purification station. A hypothesis is that mobile Fe colloids may be the link between subsurface aeration and the positive effect on the microbiological removal of NH4. The objective of this study is to characterise the mobile Fe colloids and to derive a synthetic substitute for the naturally formed Fe colloids in order to be able to apply the Fe colloids as a management tool to enhance the removal of NH4 in the process of producing drinking water from groundwater. At a purification station in The Netherlands natural Fe colloids from an aerated well were sampled. Furthermore, eight synthetic Fe colloids were prepared by oxidising synthetic solutions differing in elemental composition. The colloids were analysed using chemical analysis and electron microscopy (SEM and SEM-EDAX). The Fe colloids sampled in the field contained Fe, Ca, Na, PO4 and Mn. Also in the synthetic Fe colloids PO4, Ca, Na and Mn were the most important elements next to Fe. Phosphate and dissolved organic C strongly influenced the morphology of the synthetic Fe colloids. When both the elemental composition and the morphology of the Fe colloids are taken into account, the synthetic Fe colloids formed in the synthetic solution containing Fe, Mn, PO4, SiO4 and dissolved organic matter best match the Fe colloids from the field. (C) 2004 Elsevier Ltd. All rights reserved.
Original languageEnglish
Pages (from-to)1391-1402
JournalApplied Geochemistry
Volume19
Issue number9
DOIs
Publication statusPublished - 2004

Fingerprint

Colloids
colloid
aeration
Groundwater
groundwater
Drinking Water
Purification
Potable water
Precipitates
purification
Chemical analysis
scanning electron microscopy
drinking water
Scanning electron microscopy
Organophosphates
Biological materials
electron microscopy
Electron microscopy
dissolved organic matter
chemical analysis

Keywords

  • lepidocrocite surface
  • fe(ii) oxidation
  • eutrophic lake
  • scanning force
  • iron removal
  • phosphate
  • goethite
  • adsorption
  • transport
  • media

Cite this

Wolthoorn, A. ; Temminghoff, E.J.M. ; van Riemsdijk, W.H. / Colloid formation in groundwater by subsurface aeration: characterisation of the geo-colloids and their counterparts. In: Applied Geochemistry. 2004 ; Vol. 19, No. 9. pp. 1391-1402.
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abstract = "Subsurface aeration is used to oxidise Fe in situ in groundwater to make the water potable. In a groundwater system with pH > 7, subsurface aeration results in a non-mobile Fe precipitate and mobile Fe colloids. Since originally the goal of subsurface aeration is to remove Fe in situ, the formation of non-mobile Fe precipitate is the desired result. In addition to this intended effect, subsurface aeration may also strongly enhance the microbiological removal of NH4 in the purification station. A hypothesis is that mobile Fe colloids may be the link between subsurface aeration and the positive effect on the microbiological removal of NH4. The objective of this study is to characterise the mobile Fe colloids and to derive a synthetic substitute for the naturally formed Fe colloids in order to be able to apply the Fe colloids as a management tool to enhance the removal of NH4 in the process of producing drinking water from groundwater. At a purification station in The Netherlands natural Fe colloids from an aerated well were sampled. Furthermore, eight synthetic Fe colloids were prepared by oxidising synthetic solutions differing in elemental composition. The colloids were analysed using chemical analysis and electron microscopy (SEM and SEM-EDAX). The Fe colloids sampled in the field contained Fe, Ca, Na, PO4 and Mn. Also in the synthetic Fe colloids PO4, Ca, Na and Mn were the most important elements next to Fe. Phosphate and dissolved organic C strongly influenced the morphology of the synthetic Fe colloids. When both the elemental composition and the morphology of the Fe colloids are taken into account, the synthetic Fe colloids formed in the synthetic solution containing Fe, Mn, PO4, SiO4 and dissolved organic matter best match the Fe colloids from the field. (C) 2004 Elsevier Ltd. All rights reserved.",
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Colloid formation in groundwater by subsurface aeration: characterisation of the geo-colloids and their counterparts. / Wolthoorn, A.; Temminghoff, E.J.M.; van Riemsdijk, W.H.

In: Applied Geochemistry, Vol. 19, No. 9, 2004, p. 1391-1402.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - Colloid formation in groundwater by subsurface aeration: characterisation of the geo-colloids and their counterparts

AU - Wolthoorn, A.

AU - Temminghoff, E.J.M.

AU - van Riemsdijk, W.H.

PY - 2004

Y1 - 2004

N2 - Subsurface aeration is used to oxidise Fe in situ in groundwater to make the water potable. In a groundwater system with pH > 7, subsurface aeration results in a non-mobile Fe precipitate and mobile Fe colloids. Since originally the goal of subsurface aeration is to remove Fe in situ, the formation of non-mobile Fe precipitate is the desired result. In addition to this intended effect, subsurface aeration may also strongly enhance the microbiological removal of NH4 in the purification station. A hypothesis is that mobile Fe colloids may be the link between subsurface aeration and the positive effect on the microbiological removal of NH4. The objective of this study is to characterise the mobile Fe colloids and to derive a synthetic substitute for the naturally formed Fe colloids in order to be able to apply the Fe colloids as a management tool to enhance the removal of NH4 in the process of producing drinking water from groundwater. At a purification station in The Netherlands natural Fe colloids from an aerated well were sampled. Furthermore, eight synthetic Fe colloids were prepared by oxidising synthetic solutions differing in elemental composition. The colloids were analysed using chemical analysis and electron microscopy (SEM and SEM-EDAX). The Fe colloids sampled in the field contained Fe, Ca, Na, PO4 and Mn. Also in the synthetic Fe colloids PO4, Ca, Na and Mn were the most important elements next to Fe. Phosphate and dissolved organic C strongly influenced the morphology of the synthetic Fe colloids. When both the elemental composition and the morphology of the Fe colloids are taken into account, the synthetic Fe colloids formed in the synthetic solution containing Fe, Mn, PO4, SiO4 and dissolved organic matter best match the Fe colloids from the field. (C) 2004 Elsevier Ltd. All rights reserved.

AB - Subsurface aeration is used to oxidise Fe in situ in groundwater to make the water potable. In a groundwater system with pH > 7, subsurface aeration results in a non-mobile Fe precipitate and mobile Fe colloids. Since originally the goal of subsurface aeration is to remove Fe in situ, the formation of non-mobile Fe precipitate is the desired result. In addition to this intended effect, subsurface aeration may also strongly enhance the microbiological removal of NH4 in the purification station. A hypothesis is that mobile Fe colloids may be the link between subsurface aeration and the positive effect on the microbiological removal of NH4. The objective of this study is to characterise the mobile Fe colloids and to derive a synthetic substitute for the naturally formed Fe colloids in order to be able to apply the Fe colloids as a management tool to enhance the removal of NH4 in the process of producing drinking water from groundwater. At a purification station in The Netherlands natural Fe colloids from an aerated well were sampled. Furthermore, eight synthetic Fe colloids were prepared by oxidising synthetic solutions differing in elemental composition. The colloids were analysed using chemical analysis and electron microscopy (SEM and SEM-EDAX). The Fe colloids sampled in the field contained Fe, Ca, Na, PO4 and Mn. Also in the synthetic Fe colloids PO4, Ca, Na and Mn were the most important elements next to Fe. Phosphate and dissolved organic C strongly influenced the morphology of the synthetic Fe colloids. When both the elemental composition and the morphology of the Fe colloids are taken into account, the synthetic Fe colloids formed in the synthetic solution containing Fe, Mn, PO4, SiO4 and dissolved organic matter best match the Fe colloids from the field. (C) 2004 Elsevier Ltd. All rights reserved.

KW - lepidocrocite surface

KW - fe(ii) oxidation

KW - eutrophic lake

KW - scanning force

KW - iron removal

KW - phosphate

KW - goethite

KW - adsorption

KW - transport

KW - media

U2 - 10.1016/j.apgeochem.2004.01.023

DO - 10.1016/j.apgeochem.2004.01.023

M3 - Article

VL - 19

SP - 1391

EP - 1402

JO - Applied Geochemistry

JF - Applied Geochemistry

SN - 0883-2927

IS - 9

ER -