Determination of dynamic metal complexes and their diffusion coefficients in the presence of different humic substances by combining two analytical techniques.
IR@NIO: CSIR-National Institute Of Oceanography, Goa
View Archive Info| Field | Value | |
| Creator |
Chakraborty, P.
Manek, A. Niyogi, S. Hudson, J. |
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| Date |
2014-05-06T11:33:36Z
2014-05-06T11:33:36Z 2014 |
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| Identifier |
Analytical Letters, vol.47; 2014; 1224–1241.
http://drs.nio.org/drs/handle/2264/4524 |
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| Description |
The combined use of a competing ligand exchange (CLE) method and a diffusive gradient in thin films (DGT) technique in a quasi-labile system provides a better understanding of dynamic metal (Cu and Ni) complexes in the presence of humic substances of different origins. The CLE and DGT techniques provide total labile (dynamic) metal complexes (Cu and Ni) and their dissociation rate constants in environmental systems. DGT was found to estimate lower concentrations of labile metal complexes than CLE. These discrepancies were caused by diffusion controlled metal flux (towards the binding resin gel) in the diffusive gel of DGT. The interactions of Cu and Ni with humic acids are stronger than their interactions with fulvic acid and natural organic matter. Changes in the lability of Ni and Cu complexes (complexed with humic substances of different origins) with the changing analytical detection window indicate that the complexes of these metals were formed with different binding sites with diverse binding energies in the humic substances. The combination of these two techniques was found to be very useful in determining diffusion coefficients of labile metal-humate complexes in quasi-labile systems. The values of diffusion coefficients of labile Ni and Cu complexes determined in this study are in good agreement with limited results from the literature. This finding is novel and can be very useful in further improving our understanding of the metal humate interactions in natural environments.
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| Language |
en
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| Publisher |
Taylor & Francis
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| Rights |
The final and definitive form of the preprint has been published in the "Analytical Letters" © 2014 Taylor & Francis; "Analytical Letters" is available online at http://www.tandfonline.com with open URL of article : http://dx.doi.org/10.1080/00032719.2013.865204. The term & condition associated with this preprint is at http://www.tandfonline.com/page/terms-and-conditions
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| Subject |
diffusion coefficients
chemical speciation dynamics metal ions technology |
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| Title |
Determination of dynamic metal complexes and their diffusion coefficients in the presence of different humic substances by combining two analytical techniques.
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| Type |
Journal Article
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