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Development of a novel method for the in-situ dechlorination of immovable iron elements: optimization of Cl(−) extraction yield through experimental design

The conservation of iron objects exposed to marine aerosol is threatened by the formation of akaganeite, a highly unstable Cl-bearing corrosion phase. As akaganeite formation is responsible of the exfoliation of the rust layer, chlorides trigger a cyclic alteration phenomenon that often ends with th...

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Autores principales: Veneranda, Marco, Prieto-Taboada, Nagore, Carrero, Jose Antonio, Costantini, Ilaria, Larrañaga, Aitor, Castro, Kepa, Arana, Gorka, Madariaga, Juan Manuel
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group UK 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8144618/
https://www.ncbi.nlm.nih.gov/pubmed/34031454
http://dx.doi.org/10.1038/s41598-021-90006-y
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author Veneranda, Marco
Prieto-Taboada, Nagore
Carrero, Jose Antonio
Costantini, Ilaria
Larrañaga, Aitor
Castro, Kepa
Arana, Gorka
Madariaga, Juan Manuel
author_facet Veneranda, Marco
Prieto-Taboada, Nagore
Carrero, Jose Antonio
Costantini, Ilaria
Larrañaga, Aitor
Castro, Kepa
Arana, Gorka
Madariaga, Juan Manuel
author_sort Veneranda, Marco
collection PubMed
description The conservation of iron objects exposed to marine aerosol is threatened by the formation of akaganeite, a highly unstable Cl-bearing corrosion phase. As akaganeite formation is responsible of the exfoliation of the rust layer, chlorides trigger a cyclic alteration phenomenon that often ends with the total consumption of the iron core. To prevent this degradation process, movable iron elements (e.g. archaeometallurgical artefacts) are generally immersed in alkaline dechlorination baths. Aiming to transfer this successful method to the treatment of immovable iron objects, we propose the in-situ application of alkaline solutions through the use of highly absorbent wraps. As first step of this novel research line, the present work defines the best desalination solution to be used and optimizes its extraction yield. After literature review, a screening experimental design was performed to understand the single and synergic effects of common additives used for NaOH baths. Once the most effective variables were selected, an optimization design was carried out to determine the optimal conditions to be set during treatment. According to the experimental work here presented, the use of 0.7 M NaOH solutions applied at high temperatures (above 50 °C) is recommended. Indeed, these conditions enhance chloride extraction and iron leaching inhibition, while promoting corrosion stabilization.
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spelling pubmed-81446182021-05-26 Development of a novel method for the in-situ dechlorination of immovable iron elements: optimization of Cl(−) extraction yield through experimental design Veneranda, Marco Prieto-Taboada, Nagore Carrero, Jose Antonio Costantini, Ilaria Larrañaga, Aitor Castro, Kepa Arana, Gorka Madariaga, Juan Manuel Sci Rep Article The conservation of iron objects exposed to marine aerosol is threatened by the formation of akaganeite, a highly unstable Cl-bearing corrosion phase. As akaganeite formation is responsible of the exfoliation of the rust layer, chlorides trigger a cyclic alteration phenomenon that often ends with the total consumption of the iron core. To prevent this degradation process, movable iron elements (e.g. archaeometallurgical artefacts) are generally immersed in alkaline dechlorination baths. Aiming to transfer this successful method to the treatment of immovable iron objects, we propose the in-situ application of alkaline solutions through the use of highly absorbent wraps. As first step of this novel research line, the present work defines the best desalination solution to be used and optimizes its extraction yield. After literature review, a screening experimental design was performed to understand the single and synergic effects of common additives used for NaOH baths. Once the most effective variables were selected, an optimization design was carried out to determine the optimal conditions to be set during treatment. According to the experimental work here presented, the use of 0.7 M NaOH solutions applied at high temperatures (above 50 °C) is recommended. Indeed, these conditions enhance chloride extraction and iron leaching inhibition, while promoting corrosion stabilization. Nature Publishing Group UK 2021-05-24 /pmc/articles/PMC8144618/ /pubmed/34031454 http://dx.doi.org/10.1038/s41598-021-90006-y Text en © The Author(s) 2021 https://creativecommons.org/licenses/by/4.0/Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) .
spellingShingle Article
Veneranda, Marco
Prieto-Taboada, Nagore
Carrero, Jose Antonio
Costantini, Ilaria
Larrañaga, Aitor
Castro, Kepa
Arana, Gorka
Madariaga, Juan Manuel
Development of a novel method for the in-situ dechlorination of immovable iron elements: optimization of Cl(−) extraction yield through experimental design
title Development of a novel method for the in-situ dechlorination of immovable iron elements: optimization of Cl(−) extraction yield through experimental design
title_full Development of a novel method for the in-situ dechlorination of immovable iron elements: optimization of Cl(−) extraction yield through experimental design
title_fullStr Development of a novel method for the in-situ dechlorination of immovable iron elements: optimization of Cl(−) extraction yield through experimental design
title_full_unstemmed Development of a novel method for the in-situ dechlorination of immovable iron elements: optimization of Cl(−) extraction yield through experimental design
title_short Development of a novel method for the in-situ dechlorination of immovable iron elements: optimization of Cl(−) extraction yield through experimental design
title_sort development of a novel method for the in-situ dechlorination of immovable iron elements: optimization of cl(−) extraction yield through experimental design
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8144618/
https://www.ncbi.nlm.nih.gov/pubmed/34031454
http://dx.doi.org/10.1038/s41598-021-90006-y
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