[article]
Titre : |
Quantitative extraction of chromium VI and III from tanned leather : a comparative study of pretreatment methods |
Type de document : |
texte imprimé |
Auteurs : |
Mónica Gisel Arellano-Sánchez, Auteur ; Christine Devouge-Boyer, Auteur ; Marie Hubert-Roux, Auteur ; Carlos Afonso, Auteur ; Mélanie Mignot, Auteur |
Année de publication : |
2021 |
Article en page(s) : |
13 p. |
Note générale : |
Bibliogr. |
Langues : |
Anglais (eng) |
Catégories : |
Chrome hexavalent Complexes métalliques Cuir Ethylène diamine tétra acétiqueL'EDTA (Ethylène Diamine Tétra Acétique), ou acide éthylène diamine tétraacétique, est un acide diaminotétracarboxylique de formule C10H16N2O8.
L'EDTA comporte six sites basiques, quatre correspondant aux bases conjuguées (carboxylates) des fonctions carboxyliques et deux correspondant aux fonctions amines. Ces sites basiques sont également des centres ligands, faisant de l'EDTA un ligand hexadentate (ou parfois tétradentate, lorsque seuls les sites carboxyliques sont utilisés). C'est d'ailleurs sa principale caractéristique, son fort pouvoir chélatant (ou complexant) par lequel il forme des complexes métalliques très stables, ce qui en fait un traitement en cas d'intoxication aux métaux lourds comme le plomb, avec une concentration adaptée (Voir Applications et chélation). Dans les complexes, l'EDTA est lié aux cations métalliques sous la forme d'une de ses bases conjuguées9. Extraction (chimie) Spéciation (chimie) Technique des plasmas
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Index. décimale : |
675.2 Préparation du cuir naturel. Tannage |
Résumé : |
In this study, seven pretreatment methods for chromium speciation in tanned leather were evaluated: acidic mineralization, ethylenediaminetetraacetic acid (EDTA) extraction, diethylenetriaminepentaacetic acid (DTPA) extraction, alkaline extraction (NH4OH), ammonium nitrate extraction (NH4NO3), water extraction, and phosphate buffer extraction. Acidic mineralization permitted the decomposition of the organic matter and ensured the complete digestion of leathers, giving access to the total content of chromium in each sample using inductively coupled plasma-atomic emission spectrometry (ICP-AES). From all the extractant media tested, EDTA proved to be the most efficient, allowing the extraction of Cr(VI) and Cr(III) as a Cr(III)-EDTA complex, quantitatively. Method validation is presented for EDTA extraction and direct mineralization. For the EDTA extraction, method detection limit (MDL) and method quantification limit (MQL) for total Cr in leather were 3.4 ppb and 11.2 ppb (µg of total Cr per L of extraction solution), respectively. Due to the lack of leather certified reference materials (CRMs) for Cr(VI), accuracy was evaluated by spiking leather samples with a Cr(VI) solution. The spike recovery of EDTA microwave assisted extraction ranged from 91.0 to 108.6%. Interday precision was also evaluated and all variation coefficients were below 5%, for both mineralization and EDTA extraction. This article provides an efficient procedure to extract quantitatively chromium from leather, while maintaining the speciation, which can be further followed by ion chromatography-inductively coupled plasma-mass spectrometry (IC-ICP-MS). |
Note de contenu : |
- EXPERIMENTAL : Instrumentation - Materials - Total chromium determination - Sample preparation - Mineralization (or acidic digestion) - EDTA extraction - DTPA extraction - Alkaline extraction - Ammonium nitrate extraction - Water extraction - Phosphate buffer extraction - Sample spiking - Speciation by IC-ICP-MS
- RESULTS AND DISCUSSION : Evaluation of different pretreatment methods - Validation of the method - Speciation by IC-ICP-MS
- Table 1 : Pretreatment and determination methods for hexavalent chromium in leather samples
- Table 2 : Optimized operating conditions for ICP-AES and ICP-MS
- Table 3 : Extraction rates of different pretreatment methods. Comparison between direct mineralization and : a EDTA extraction ; b DTPA extraction ; c NH4OH extraction ; d NH4NO3 extraction ; e water extraction ; f phosphate buffer extraction ; 3 different samples were analyzed each day
- Table 4 : Interday precision of: a direct mineralization ; b EDTA extraction. 3 different samples were analyzed each day
- Table 5 : Spike recovery for : a direct mineralization ; b EDTA extraction |
DOI : |
https://doi.org/10.1186/s42825-021-00071-2 |
En ligne : |
https://link.springer.com/content/pdf/10.1186/s42825-021-00071-2.pdf |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37555 |
in JOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 3 (Année 2021) . - 13 p.
[article]
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