To gain a deeper understanding of the geochemical processes involved in the interactions between ionic solutions and clay minerals in natural systems, the dissolution rate of an Fe-rich saponite from Mt. Prinzera (Taro Valley, Italy) was measured as a function of pH and time at 25 degrees C. Also, its ability to adsorb Cr was studied at varying metal concentrations (3.22, 5.50, 8.50 mEq l(-1)) and with different competing anions (CH3COO-, Cl-, NO3-). It was found that there is a correlation between the experimentally determined release rate constant (k), as defined by the relase of Si, and pH. In acidic solutions, the k values correlate negatively with pH, whereas the opposite occurs for basic solutions. The extent of Cr uptake was measured by analysis of the liquid portion separated by centrifugation after a controlled period of exposure. The Cr adsorbed for different concentrations and anionic environments shows the dependence of Cr uptake on the initial metal concentration and on accompanying anions in the order CH3COO- < Cl- < NO3-.

Iron-rich saponite: dissolution reactions and Cr uptake / Brigatti, Maria Franca; Lugli, Cristina; Poppi, Luciano; G., Venturelli. - In: CLAY MINERALS. - ISSN 0009-8558. - STAMPA. - 34:(1999), pp. 637-645. [10.1180/000985599546497]

Iron-rich saponite: dissolution reactions and Cr uptake

BRIGATTI, Maria Franca;LUGLI, Cristina;POPPI, Luciano;
1999

Abstract

To gain a deeper understanding of the geochemical processes involved in the interactions between ionic solutions and clay minerals in natural systems, the dissolution rate of an Fe-rich saponite from Mt. Prinzera (Taro Valley, Italy) was measured as a function of pH and time at 25 degrees C. Also, its ability to adsorb Cr was studied at varying metal concentrations (3.22, 5.50, 8.50 mEq l(-1)) and with different competing anions (CH3COO-, Cl-, NO3-). It was found that there is a correlation between the experimentally determined release rate constant (k), as defined by the relase of Si, and pH. In acidic solutions, the k values correlate negatively with pH, whereas the opposite occurs for basic solutions. The extent of Cr uptake was measured by analysis of the liquid portion separated by centrifugation after a controlled period of exposure. The Cr adsorbed for different concentrations and anionic environments shows the dependence of Cr uptake on the initial metal concentration and on accompanying anions in the order CH3COO- < Cl- < NO3-.
34
637
645
Iron-rich saponite: dissolution reactions and Cr uptake / Brigatti, Maria Franca; Lugli, Cristina; Poppi, Luciano; G., Venturelli. - In: CLAY MINERALS. - ISSN 0009-8558. - STAMPA. - 34:(1999), pp. 637-645. [10.1180/000985599546497]
Brigatti, Maria Franca; Lugli, Cristina; Poppi, Luciano; G., Venturelli
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

Licenza Creative Commons
I metadati presenti in IRIS UNIMORE sono rilasciati con licenza Creative Commons CC0 1.0 Universal, mentre i file delle pubblicazioni sono rilasciati con licenza Attribuzione 4.0 Internazionale (CC BY 4.0), salvo diversa indicazione.
In caso di violazione di copyright, contattare Supporto Iris

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11380/303808
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 8
  • ???jsp.display-item.citation.isi??? 8
social impact