Stream waters draining an old mining area present very high rare earth element (REE) contents, reaching 928 μg/l as the maximum total value (ΣREE). The middle rare earth elements (MREEs) are usually enriched with respect to both the light (LREEs) and heavy (HREEs) elements of this group, producing a characteristic “roof-shaped” pattern of the shale Post-Archean Australian Shales-normalized concentrations. At the Fenice Capanne Mine (FCM), the most important base metal mine of the study area, the REE source coincides with the mine tailings, mostly the oldest ones composed of iron-rich materials. The geochemical history of the REEs released into Noni stream from wastes in the FCM area is strictly determined by the pH, which controls the REE speciation and in-stream processes. The formation of Al-rich and mainly Fe-rich flocs effectively scavenges the REEs, which are readily and drastically removed from the solution when the pH approaches neutrality. Leaching experiments performed on flocs and waste materials demonstrate that Fe-oxides/oxyhydroxides play a key role in the release of lanthanide elements into stream waters. The origin of the “roof-shaped” REE distribution pattern as well as the peculiar geochemical behavior of some lanthanide elements in the aqueous system are discussed.

Protano, G., Riccobono, F. (2002). High contents of rare earth elements (REEs) in stream waters of a Cu-Pb-Zn mining area. ENVIRONMENTAL POLLUTION, 117(3), 499-514 [10.1016/S0269-7491(01)00173-7].

High contents of rare earth elements (REEs) in stream waters of a Cu-Pb-Zn mining area

PROTANO, G.;RICCOBONO, F.
2002-01-01

Abstract

Stream waters draining an old mining area present very high rare earth element (REE) contents, reaching 928 μg/l as the maximum total value (ΣREE). The middle rare earth elements (MREEs) are usually enriched with respect to both the light (LREEs) and heavy (HREEs) elements of this group, producing a characteristic “roof-shaped” pattern of the shale Post-Archean Australian Shales-normalized concentrations. At the Fenice Capanne Mine (FCM), the most important base metal mine of the study area, the REE source coincides with the mine tailings, mostly the oldest ones composed of iron-rich materials. The geochemical history of the REEs released into Noni stream from wastes in the FCM area is strictly determined by the pH, which controls the REE speciation and in-stream processes. The formation of Al-rich and mainly Fe-rich flocs effectively scavenges the REEs, which are readily and drastically removed from the solution when the pH approaches neutrality. Leaching experiments performed on flocs and waste materials demonstrate that Fe-oxides/oxyhydroxides play a key role in the release of lanthanide elements into stream waters. The origin of the “roof-shaped” REE distribution pattern as well as the peculiar geochemical behavior of some lanthanide elements in the aqueous system are discussed.
2002
Protano, G., Riccobono, F. (2002). High contents of rare earth elements (REEs) in stream waters of a Cu-Pb-Zn mining area. ENVIRONMENTAL POLLUTION, 117(3), 499-514 [10.1016/S0269-7491(01)00173-7].
File in questo prodotto:
File Dimensione Formato  
Protano_et_al_2002.pdf

non disponibili

Descrizione: Articolo
Tipologia: PDF editoriale
Licenza: NON PUBBLICO - Accesso privato/ristretto
Dimensione 431.59 kB
Formato Adobe PDF
431.59 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11365/27052