Correlation of oxidated and reduced forms of noble metals in the Amur region

About the authors:

Sergey M. Radomskiу, Cand. Geol.-Min. Sci., principal researcher, Institute of Geology and Nature Management of FEB RAS
Valentina I. Radomskaya , Cand. Chem. Sci., principal researcher, Institute of Geology and Nature Management of FEB RAS

Abstract:

Noble metals (NM) are extended in nature extremely unevenly. The oxidation of minerals NM is accomplished over the surface and is described by the second law of thermodynamics and by the equation of Nernst. Important task is the determination of the individual forms of the presence NM of the oxidized form — Сox. characterizing migration and scattering in the natural medium and of the reduced form — Cred., that characterizes mineral accumulation. For the determination Сox. in practice, it is proposed to separate by filtration the oxidized forms from the reduced forms NM with heating of the hinge quantity of test in the solution of 3M HCl to the boiling point. In the filtrate remain Сox., while in the sediment Cred. the forms NM. The concentrations of the reduced forms Cred. of NM also can be determined according to the equation Cred. = Cgross — Сox., where Cgross — general concentration NM in the test. Connection (Сox./Cred.) individual NM with the geometric dimensions by us is given by equation (1), where n — quantity of minerals, which is changed from i = 1, 2,…, n, i — ordinal number of mineral, ri — radius i of mineral, — the middle radius of minerals in μm; = Σri/n; Ssp — area of sphere; Vsp — volume of the sphere: . For the surface water, the soils, the plants were determined Сox./Cred., the corresponding for the predominantly elapsing process mineral formations NM above their scattering in the natural landscapes. It is shown that a quantity of oxidized forms NM depends on chemical nature individual NM, its gross concentration, middle radius of its minerals and physical chemistry properties of the open fixed system (temperature, pressure, pH, Eh).

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