The stability of the rare sodium antimonate, brizziite, and it's role in Sb mobility

Adam J. Roper*, Peter Leverett, Timothy D. Murphy, Peter A. Williams

*Corresponding author for this work

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Synthesis and solubility studies of brizziite, NaSbO3, have been undertaken to determine the possible role of this rare secondary phase in the immobilization of Sb under supergene conditions and the conditions responsible for its formation in the supergene zone. Solubility studies were undertaken at T = 298.15 K. A value of ΔGf e) (NaSbO3, s, 298.15 K) = -806.66 ± 1.4 kJ mol-1 was derived. Calculations involving tripuhyite, FeSbO4, byströmite, MgSb2O6, ordoñezite, ZnSb2O6 and rosiaite, PbSb2O6, show that brizziite is a thermodynamically stable phase only at negligible activities of Pb2+(aq) at high pH and high salinity. Calculations involving mopungite Na[Sb(OH)6] combined with reported mineral associations suggest that mopungite is the thermodynamically unstable precursor to brizziite and its presence in natural settings must be due to kinetic stability. This explains why brizziite is such a rare secondary phase and therefore why it cannot exert any significant influence on the dispersion of Sb in the supergene environment.

Original languageEnglish
Pages (from-to)89-93
Number of pages5
JournalMineralogical Magazine
Volume82
Issue number1
DOIs
Publication statusPublished - Feb 2018
Externally publishedYes

Keywords

  • brizziite
  • antimony
  • solubility
  • stability
  • chemical mineralogy
  • supergene zone

Fingerprint Dive into the research topics of 'The stability of the rare sodium antimonate, brizziite, and it's role in Sb mobility'. Together they form a unique fingerprint.

Cite this