Association of calcium with colloidal particles and speciation of calcium in the Kalix and Amazon rivers
A considerable amount of colloidally bound Ca has been detected in water samples from Amazonian rivers and the Kalix River, a sub-arctic boreal river. Fractionation experiments using several analytical techniques and processing tools were conducted in order to elucidate the matter. Results show that...
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Format: | Article in Journal/Newspaper |
Language: | English |
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Luleå tekniska universitet, Geovetenskap och miljöteknik
2004
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Online Access: | http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-15921 https://doi.org/10.1016/j.gca.2004.04.007 |
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ftluleatu:oai:DiVA.org:ltu-15921 2023-05-15T15:15:41+02:00 Association of calcium with colloidal particles and speciation of calcium in the Kalix and Amazon rivers Dahlqvist, Ralf Benedetti, Marc F. Andersson, Karen Turner, David Larsson, Tobias Stolpe, Björn Ingri, Johan 2004 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-15921 https://doi.org/10.1016/j.gca.2004.04.007 eng eng Luleå tekniska universitet, Geovetenskap och miljöteknik Department of Geology and Geochemistry, Stockholm University Laboratorie de Géochimie et Métallogénie, Universite Pierre et Marie Curie, Paris Department of Chemistry, Analytical and Marine Chemistry, Göteborg University Geochimica et Cosmochimica Acta, 0016-7037, 2004, 68:20, s. 4059-4075 http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-15921 doi:10.1016/j.gca.2004.04.007 ISI:000224514900003 Scopus 2-s2.0-5044235039 Local f7ed2750-7b31-11db-8824-000ea68e967b info:eu-repo/semantics/openAccess Geochemistry Geokemi Article in journal info:eu-repo/semantics/article text 2004 ftluleatu https://doi.org/10.1016/j.gca.2004.04.007 2022-10-25T20:54:32Z A considerable amount of colloidally bound Ca has been detected in water samples from Amazonian rivers and the Kalix River, a sub-arctic boreal river. Fractionation experiments using several analytical techniques and processing tools were conducted in order to elucidate the matter. Results show that on average 84% of the total Ca concentration is present as free Ca. Particulate, colloidal and complexed Ca constitute the remaining 16%, of which the colloidal fraction is significant. Ultrafiltration experiments show that the colloidal fraction in the sampled Amazonian rivers and the Kalix River range between 1% and 25%. In both the Amazonian and the Kalix rivers the technique of cross-flow ultrafiltration was used to isolate particles and colloids. The difference in concentration measured with ICP-AES and a Ca ion-selective electrode in identical samples was used to define the free Ca concentration and thus indirectly the magnitude of the particulate, colloidal and complexed fractions. Results from the Kalix and Amazonian rivers are in excellent agreement. Furthermore, the results show that the colloidal concentrations of Ca can be greatly overestimated (up to 227%) when conventional analysis and calculation of ultrafiltration data is used due to retention of free Ca ions during the ultrafiltration process. Calculation methods for colloidal matter are presented in this work, using complementary data from ISE analysis. In the Kalix River temporal changes in the fractionation of Ca were studied before, during and after a spring-flood event. Changes in the size distribution of colloidally associated Ca was studied using FlFFF (Flow Field-Flow Fractionation) coupled on-line to a HR ICP-MS. The FlFFF–HR ICP-MS fractograms clearly show the colloidal component of Ca, supporting the ultrafiltration findings. During winter conditions the size distribution of colloidally associated Ca has a concentration maximum at 5 to 10 nm in diameter, shifting to smaller sizes (<5 nm) during and after the spring flood. This shift in ... Article in Journal/Newspaper Arctic Luleå University of Technology Publications (DiVA) Arctic Kalix ENVELOPE(23.156,23.156,65.853,65.853) Geochimica et Cosmochimica Acta 68 20 4059 4075 |
institution |
Open Polar |
collection |
Luleå University of Technology Publications (DiVA) |
op_collection_id |
ftluleatu |
language |
English |
topic |
Geochemistry Geokemi |
spellingShingle |
Geochemistry Geokemi Dahlqvist, Ralf Benedetti, Marc F. Andersson, Karen Turner, David Larsson, Tobias Stolpe, Björn Ingri, Johan Association of calcium with colloidal particles and speciation of calcium in the Kalix and Amazon rivers |
topic_facet |
Geochemistry Geokemi |
description |
A considerable amount of colloidally bound Ca has been detected in water samples from Amazonian rivers and the Kalix River, a sub-arctic boreal river. Fractionation experiments using several analytical techniques and processing tools were conducted in order to elucidate the matter. Results show that on average 84% of the total Ca concentration is present as free Ca. Particulate, colloidal and complexed Ca constitute the remaining 16%, of which the colloidal fraction is significant. Ultrafiltration experiments show that the colloidal fraction in the sampled Amazonian rivers and the Kalix River range between 1% and 25%. In both the Amazonian and the Kalix rivers the technique of cross-flow ultrafiltration was used to isolate particles and colloids. The difference in concentration measured with ICP-AES and a Ca ion-selective electrode in identical samples was used to define the free Ca concentration and thus indirectly the magnitude of the particulate, colloidal and complexed fractions. Results from the Kalix and Amazonian rivers are in excellent agreement. Furthermore, the results show that the colloidal concentrations of Ca can be greatly overestimated (up to 227%) when conventional analysis and calculation of ultrafiltration data is used due to retention of free Ca ions during the ultrafiltration process. Calculation methods for colloidal matter are presented in this work, using complementary data from ISE analysis. In the Kalix River temporal changes in the fractionation of Ca were studied before, during and after a spring-flood event. Changes in the size distribution of colloidally associated Ca was studied using FlFFF (Flow Field-Flow Fractionation) coupled on-line to a HR ICP-MS. The FlFFF–HR ICP-MS fractograms clearly show the colloidal component of Ca, supporting the ultrafiltration findings. During winter conditions the size distribution of colloidally associated Ca has a concentration maximum at 5 to 10 nm in diameter, shifting to smaller sizes (<5 nm) during and after the spring flood. This shift in ... |
format |
Article in Journal/Newspaper |
author |
Dahlqvist, Ralf Benedetti, Marc F. Andersson, Karen Turner, David Larsson, Tobias Stolpe, Björn Ingri, Johan |
author_facet |
Dahlqvist, Ralf Benedetti, Marc F. Andersson, Karen Turner, David Larsson, Tobias Stolpe, Björn Ingri, Johan |
author_sort |
Dahlqvist, Ralf |
title |
Association of calcium with colloidal particles and speciation of calcium in the Kalix and Amazon rivers |
title_short |
Association of calcium with colloidal particles and speciation of calcium in the Kalix and Amazon rivers |
title_full |
Association of calcium with colloidal particles and speciation of calcium in the Kalix and Amazon rivers |
title_fullStr |
Association of calcium with colloidal particles and speciation of calcium in the Kalix and Amazon rivers |
title_full_unstemmed |
Association of calcium with colloidal particles and speciation of calcium in the Kalix and Amazon rivers |
title_sort |
association of calcium with colloidal particles and speciation of calcium in the kalix and amazon rivers |
publisher |
Luleå tekniska universitet, Geovetenskap och miljöteknik |
publishDate |
2004 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-15921 https://doi.org/10.1016/j.gca.2004.04.007 |
long_lat |
ENVELOPE(23.156,23.156,65.853,65.853) |
geographic |
Arctic Kalix |
geographic_facet |
Arctic Kalix |
genre |
Arctic |
genre_facet |
Arctic |
op_relation |
Geochimica et Cosmochimica Acta, 0016-7037, 2004, 68:20, s. 4059-4075 http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-15921 doi:10.1016/j.gca.2004.04.007 ISI:000224514900003 Scopus 2-s2.0-5044235039 Local f7ed2750-7b31-11db-8824-000ea68e967b |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1016/j.gca.2004.04.007 |
container_title |
Geochimica et Cosmochimica Acta |
container_volume |
68 |
container_issue |
20 |
container_start_page |
4059 |
op_container_end_page |
4075 |
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1766346030926790656 |