Research output: Contribution to journal › Article › peer-review
A Calorimetric and Thermodynamic Investigation of the Synthetic Analogue of Mandarinoite, Fe2(SeO3)3∙5H2O. / Lelet, Maxim I.; Charykova , Marina V.; Holzheid , Astrid; Ledwig , Brenan; Krivovichev, Vladimir G.; Suleimanov, Evgeny V.
In: Geosciences (Switzerland), Vol. 8, No. 11, 391, 11.2018.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - A Calorimetric and Thermodynamic Investigation of the Synthetic Analogue of Mandarinoite, Fe2(SeO3)3∙5H2O.
AU - Lelet, Maxim I.
AU - Charykova , Marina V.
AU - Holzheid , Astrid
AU - Ledwig , Brenan
AU - Krivovichev, Vladimir G.
AU - Suleimanov, Evgeny V.
N1 - Lelet, M.I.; Charykova, M.V.; Holzheid, A.; Ledwig, B.; Krivovichev, V.G.; Suleimanov, E.V. A Calorimetric and Thermodynamic Investigation of the Synthetic Analogue of Mandarinoite, Fe2(SeO3)3∙5H2O. Geosciences 2018, 8, 391.
PY - 2018/11
Y1 - 2018/11
N2 - Thermophysical and thermochemical calorimetric investigations were carried out on the synthetic analogue of mandarinoite. The low-temperature heat capacity of Fe2(SeO3)3∙5H2O(cr) was measured using adiabatic calorimetry between 5.3 and 324.8 K, and the third-law entropy was determined. Using these Cp,mo(T) data, the third law entropy at T = 298.15 K, Smo, is calculated as 520.1 ± 1.1 J∙K–1∙mol–1. Smoothed Cp,moT values between T →0 K and 320 K are presented, along with values for Smo and the functions [HmoT-Hmo0] and [ΦmoT-Φmo0]. The enthalpy of formation of Fe2(SeO3)3∙5H2O(cr) was determined by solution calorimetry with HF solution as the solvent, giving ΔfHmo(298 К, Fe2(SeO3)3∙5H2O, cr) = –3124.6 ± 5.3 kJ/mol. The standard Gibbs energy of formation for Fe2(SeO3)3∙5H2O(cr) at T = 298 K can be calculated on the basis on ΔfHmo(298 К) and ΔfSmo(298 К): ΔfGmo(298 К, Fe2(SeO3)3∙5H2O, cr) = ‒2600.8 ± 5.4 kJ/mol. The value of ΔfGm for Fe2(SeO3)3·5H2O(cr) was used to calculate the Eh–pH diagram of the Fe–Se–H2O system. This diagram has been constructed for the average contents of these elements in acidic waters of the oxidation zones of sulfide deposits. The behaviors of selenium and iron in the surface environment have been quantitatively explained by variations of the redox potential and the acidity-basicity of the mineral-forming medium. These parameters precisely determine the migration ability of selenium compounds and its precipitation in the form of solid phases.
AB - Thermophysical and thermochemical calorimetric investigations were carried out on the synthetic analogue of mandarinoite. The low-temperature heat capacity of Fe2(SeO3)3∙5H2O(cr) was measured using adiabatic calorimetry between 5.3 and 324.8 K, and the third-law entropy was determined. Using these Cp,mo(T) data, the third law entropy at T = 298.15 K, Smo, is calculated as 520.1 ± 1.1 J∙K–1∙mol–1. Smoothed Cp,moT values between T →0 K and 320 K are presented, along with values for Smo and the functions [HmoT-Hmo0] and [ΦmoT-Φmo0]. The enthalpy of formation of Fe2(SeO3)3∙5H2O(cr) was determined by solution calorimetry with HF solution as the solvent, giving ΔfHmo(298 К, Fe2(SeO3)3∙5H2O, cr) = –3124.6 ± 5.3 kJ/mol. The standard Gibbs energy of formation for Fe2(SeO3)3∙5H2O(cr) at T = 298 K can be calculated on the basis on ΔfHmo(298 К) and ΔfSmo(298 К): ΔfGmo(298 К, Fe2(SeO3)3∙5H2O, cr) = ‒2600.8 ± 5.4 kJ/mol. The value of ΔfGm for Fe2(SeO3)3·5H2O(cr) was used to calculate the Eh–pH diagram of the Fe–Se–H2O system. This diagram has been constructed for the average contents of these elements in acidic waters of the oxidation zones of sulfide deposits. The behaviors of selenium and iron in the surface environment have been quantitatively explained by variations of the redox potential and the acidity-basicity of the mineral-forming medium. These parameters precisely determine the migration ability of selenium compounds and its precipitation in the form of solid phases.
KW - Adiabatic calorimetry
KW - Enthalpy of formation
KW - Entropy
KW - Heat capacity
KW - Mandarinoite
KW - The gibbs energy of formation
KW - SULFATES
KW - ARSENATES
KW - heat capacity
KW - SULFIDE ORES
KW - ZINC
KW - SOLUBILITY
KW - adiabatic calorimetry
KW - entropy
KW - enthalpy of formation
KW - mandarinoite
KW - CHALCOMENITE
KW - SYSTEMS
KW - SELENITES
KW - the Gibbs energy of formation
KW - OXIDATION ZONE
KW - HEAT-CAPACITY
UR - http://www.scopus.com/inward/record.url?scp=85056266788&partnerID=8YFLogxK
U2 - 10.3390/geosciences8110391
DO - 10.3390/geosciences8110391
M3 - Article
VL - 8
JO - Geosciences (Switzerland)
JF - Geosciences (Switzerland)
SN - 2076-3263
IS - 11
M1 - 391
ER -
ID: 35316568