TY - JOUR

T1 - Термодинамика арсенатов, селенитов и сульфатов в зоне окисления сульфидных руд. XIII. Расчет стандартных термодинамических функций образования кобальтоменита, альфельдита и халькоменита из данных по растворимости

AU - Вишневский, Андрей Вячеславович

AU - Белогуб, Е. В.

AU - Чарыкова, М.В.

AU - Кривовичев, В.Г.

AU - Блинов, И.А.

PY - 2016

Y1 - 2016

N2 - Understanding mechanisms of selenium's behavior in the near-surface conditions is an actual problem of the modern mineralogy and geochemistry, and it is very important for solving some environmental challenges. The aim of the present work is to define the Gibbs energy of formation (Δ f G 0 ) for synthetic analogues of three minerals: cobaltomenite (CoSeO 3 2H 2 O), alpheldite (NiSeO 3 2H 2 O) and chalcomenite (CuSeO 3 2H 2 O) on the base of their solubility in water. Solubility was determined by the isothermal saturation method in ampoules at temperature 25 °C. Calculations of ions' activities in the solution in equilibrium with solid phases were spent by means of the software package Geochemist's Workbench (GMB 9.0). It has been revealed that dissolution of cobaltomenite, alpheldite and chalcomenite is the incongruent one and accompanied by formation of Co, Ni and hydroxides. Detected Δ f G 0 values are: CoSeO 3 2H 2 O = -937.5 kJ/mol, NiSeO 3 2H 2 O = -931.3 kJ/mol, and Cu-SeO 3 2H 2 O = -836.3 kJ/mol. These data are well corresponding to the Δ f G 0 values obtained by calorimetric investigations of thermodynamic characteristics of synthetic analogs of cobaltomenite, ahlfeldite and chalcomenite.

AB - Understanding mechanisms of selenium's behavior in the near-surface conditions is an actual problem of the modern mineralogy and geochemistry, and it is very important for solving some environmental challenges. The aim of the present work is to define the Gibbs energy of formation (Δ f G 0 ) for synthetic analogues of three minerals: cobaltomenite (CoSeO 3 2H 2 O), alpheldite (NiSeO 3 2H 2 O) and chalcomenite (CuSeO 3 2H 2 O) on the base of their solubility in water. Solubility was determined by the isothermal saturation method in ampoules at temperature 25 °C. Calculations of ions' activities in the solution in equilibrium with solid phases were spent by means of the software package Geochemist's Workbench (GMB 9.0). It has been revealed that dissolution of cobaltomenite, alpheldite and chalcomenite is the incongruent one and accompanied by formation of Co, Ni and hydroxides. Detected Δ f G 0 values are: CoSeO 3 2H 2 O = -937.5 kJ/mol, NiSeO 3 2H 2 O = -931.3 kJ/mol, and Cu-SeO 3 2H 2 O = -836.3 kJ/mol. These data are well corresponding to the Δ f G 0 values obtained by calorimetric investigations of thermodynamic characteristics of synthetic analogs of cobaltomenite, ahlfeldite and chalcomenite.

M3 - статья

VL - 145

SP - 110

EP - 117

JO - ЗАПИСКИ РОССИЙСКОГО МИНЕРАЛОГИЧЕСКОГО ОБЩЕСТВА

JF - ЗАПИСКИ РОССИЙСКОГО МИНЕРАЛОГИЧЕСКОГО ОБЩЕСТВА

SN - 0869-6055

IS - 5

ER -