Influence of dissolved organic carbon on the efficiency of P sequestration by a lanthanum modified clay

Line Dithmer, Ulla Gro Nielsen, Daniel Lundberg, Kasper Reitzel

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

Resumé

A laboratory scale experiment was set up to test the effect of dissolved organic carbon (DOC) as well as ageing of the La–P complex formed during phosphorus (P) sequestration by a La modified clay (Phoslock®). Short term (7 days) P adsorption studies revealed a significant negative effect of added DOC on the P sequestration of Phoslock®, whereas a long-term P adsorption experiment revealed that the negative effect of added DOC was reduced with time. The reduced P binding efficiency is kinetic, as evident from solid-state 31P magic-angle spinning (MAS) NMR spectroscopy, who showed that the P binding did not change in the presence of DOC. 31P MAS NMR also reveals that up to 26% of the sequestered phosphate is as loosely bound redox-sensitive P species on the surface of rhabdophane (LaPO4 · nH2O, n ≤ 3). The ratio between the loosely bound P and lanthanum phosphate did not change with time, however both NMR and La LIII-extended x-ray absorption fine structure (EXAFS) spectroscopy shows a transformation of lanthanum phosphate from the initially formed rhabdophane towards the more stable monazite (LaPO4). Furthermore, the effect of natural DOC on the P binding capacity was tested using water and pore water from 16 Danish lakes. Whilst DOC has an immediate negative impact on P binding in the lake water, with time this effect is reduced.
OriginalsprogEngelsk
TidsskriftWater Research
Vol/bind97
Udgave nummerJune
Sider (fra-til)39-46
ISSN0043-1354
DOI
StatusUdgivet - 2016

Citer dette

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title = "Influence of dissolved organic carbon on the efficiency of P sequestration by a lanthanum modified clay",
abstract = "A laboratory scale experiment was set up to test the effect of dissolved organic carbon (DOC) as well as ageing of the La–P complex formed during phosphorus (P) sequestration by a La modified clay (Phoslock{\circledR}). Short term (7 days) P adsorption studies revealed a significant negative effect of added DOC on the P sequestration of Phoslock{\circledR}, whereas a long-term P adsorption experiment revealed that the negative effect of added DOC was reduced with time. The reduced P binding efficiency is kinetic, as evident from solid-state 31P magic-angle spinning (MAS) NMR spectroscopy, who showed that the P binding did not change in the presence of DOC. 31P MAS NMR also reveals that up to 26{\%} of the sequestered phosphate is as loosely bound redox-sensitive P species on the surface of rhabdophane (LaPO4 · nH2O, n ≤ 3). The ratio between the loosely bound P and lanthanum phosphate did not change with time, however both NMR and La LIII-extended x-ray absorption fine structure (EXAFS) spectroscopy shows a transformation of lanthanum phosphate from the initially formed rhabdophane towards the more stable monazite (LaPO4). Furthermore, the effect of natural DOC on the P binding capacity was tested using water and pore water from 16 Danish lakes. Whilst DOC has an immediate negative impact on P binding in the lake water, with time this effect is reduced.",
author = "Line Dithmer and Nielsen, {Ulla Gro} and Daniel Lundberg and Kasper Reitzel",
year = "2016",
doi = "10.1016/j.watres.2015.07.003",
language = "English",
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Influence of dissolved organic carbon on the efficiency of P sequestration by a lanthanum modified clay. / Dithmer, Line; Nielsen, Ulla Gro; Lundberg, Daniel; Reitzel, Kasper.

I: Water Research, Bind 97, Nr. June, 2016, s. 39-46.

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

TY - JOUR

T1 - Influence of dissolved organic carbon on the efficiency of P sequestration by a lanthanum modified clay

AU - Dithmer, Line

AU - Nielsen, Ulla Gro

AU - Lundberg, Daniel

AU - Reitzel, Kasper

PY - 2016

Y1 - 2016

N2 - A laboratory scale experiment was set up to test the effect of dissolved organic carbon (DOC) as well as ageing of the La–P complex formed during phosphorus (P) sequestration by a La modified clay (Phoslock®). Short term (7 days) P adsorption studies revealed a significant negative effect of added DOC on the P sequestration of Phoslock®, whereas a long-term P adsorption experiment revealed that the negative effect of added DOC was reduced with time. The reduced P binding efficiency is kinetic, as evident from solid-state 31P magic-angle spinning (MAS) NMR spectroscopy, who showed that the P binding did not change in the presence of DOC. 31P MAS NMR also reveals that up to 26% of the sequestered phosphate is as loosely bound redox-sensitive P species on the surface of rhabdophane (LaPO4 · nH2O, n ≤ 3). The ratio between the loosely bound P and lanthanum phosphate did not change with time, however both NMR and La LIII-extended x-ray absorption fine structure (EXAFS) spectroscopy shows a transformation of lanthanum phosphate from the initially formed rhabdophane towards the more stable monazite (LaPO4). Furthermore, the effect of natural DOC on the P binding capacity was tested using water and pore water from 16 Danish lakes. Whilst DOC has an immediate negative impact on P binding in the lake water, with time this effect is reduced.

AB - A laboratory scale experiment was set up to test the effect of dissolved organic carbon (DOC) as well as ageing of the La–P complex formed during phosphorus (P) sequestration by a La modified clay (Phoslock®). Short term (7 days) P adsorption studies revealed a significant negative effect of added DOC on the P sequestration of Phoslock®, whereas a long-term P adsorption experiment revealed that the negative effect of added DOC was reduced with time. The reduced P binding efficiency is kinetic, as evident from solid-state 31P magic-angle spinning (MAS) NMR spectroscopy, who showed that the P binding did not change in the presence of DOC. 31P MAS NMR also reveals that up to 26% of the sequestered phosphate is as loosely bound redox-sensitive P species on the surface of rhabdophane (LaPO4 · nH2O, n ≤ 3). The ratio between the loosely bound P and lanthanum phosphate did not change with time, however both NMR and La LIII-extended x-ray absorption fine structure (EXAFS) spectroscopy shows a transformation of lanthanum phosphate from the initially formed rhabdophane towards the more stable monazite (LaPO4). Furthermore, the effect of natural DOC on the P binding capacity was tested using water and pore water from 16 Danish lakes. Whilst DOC has an immediate negative impact on P binding in the lake water, with time this effect is reduced.

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DO - 10.1016/j.watres.2015.07.003

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