Publication Date:
2020-08-05
Description:
To clarify the element partitioning behavior between minerals and aqueous chloride solutions, we conducted experiments to investigate simultaneous partitioning of Ni2+, Mg2+, Co2+, Zn2+, Fe2+, and Mn2+ ions between alabandite (MnS) and 1 mol/L (Ni, Mg, Co, Zn, Fe)Cl2 aqueous solutions at 500–800 °C and 100 MPa. The bulk partition coefficients calculated using the following equation were in the order of Fe2+ 〉 Co2+ 〉 Ni2+ ≈ Zn2+ 〉 Mn2+ 〉〉 Mg2+; KPN = (xMeS/mMeaq)/(xMnS/mMnaq). A partition coefficient-ionic radius (PC-IR) curve was plotted with the logarithmic value of the partition coefficient on the y-axis and the ionic radius at the six-fold coordinated site on the x-axis. The peak of this curve was located near the ionic radius of Fe2+ and not near the ionic radius of Mn2+. Zn2+ showed a slight negative partitioning anomaly, which increased in the order of sulfide minerals 〈 arsenic sulfide minerals 〈 arsenide minerals as the covalent bond became stronger. Ni2+ showed a positive partitioning anomaly, which indicated that it preferred an octahedral structure. The width of the PC-IR curve decreased in the order of sulfide minerals 〉 arsenic sulfide minerals 〉 arsenide minerals as the covalent bond became stronger, that is, the ion selectivity became stronger.
Electronic ISSN:
2075-163X
Topics:
Geosciences
Permalink