Thermodynamic properties of high-temperature aqueous solutions. X. Electrode potentials of sulfate ion electrodes from 0 to 100.deg.. Activity coefficients and the entropy of aqueous sulfuric acid

1969 ◽  
Vol 73 (6) ◽  
pp. 2021-2024 ◽  
Author(s):  
William L. Gardner ◽  
R. E. Mitchell ◽  
J. W. Cobble
Keyword(s):  
Sulfuric Acid ◽  
High Temperature ◽  
Thermodynamic Properties ◽  
Aqueous Solutions ◽  
Activity Coefficients ◽  
Sulfate Ion ◽  
Aqueous Sulfuric Acid ◽  
Electrode Potentials

Octahedral–tetrahedral equilibria in aqueous cobalt(II) solutions at high temperatures

1980 ◽  
Vol 58 (14) ◽  
pp. 1418-1426 ◽  
Author(s):  
Thomas Wilson Swaddle ◽  
Leonard Fabes
Keyword(s):  
Sulfuric Acid ◽  
High Temperature ◽  
Absorption Band ◽  
High Temperatures ◽  
Intensity Ratio ◽  
Hydrogen Sulfate ◽  
Sulfate Ion ◽  
Acidic Media ◽  
Visible Absorption ◽  
Upper Limits

Evidence is presented to indicate that aqueous Co2+ exists as the hexaaquo-ion in equilibrium with minor amounts (upper limits 0.08% at 298 K, 7% at 625 K, at 16–25 MPa) of tetraaquocobalt(II), with ΔH ~ +17 kJ mol−1. The single visible absorption band of the supposed Co(H2O)42+ has maxima at 552 nm and 486 nm in the intensity ratio 2:1. Hydrogen sulfate ion (up to 0.5 M at least) does not complex Co2+(aq) detectably in acidic media, 290–625 K, and sulfuric acid therefore holds promise as a non-complexing strong monobasic acid for high-temperature aqueous studies. In water containing 2.0 M or more Cl−, the tetrahedral form of cobalt(II) is CoCl42−, ΔH for the octahedral → tetrahedral equilibrium being +62 kJ mol−1; forCoBr42−, the corresponding ΔH is +70 kJ mol−1, the greater endothermicity accounting entirely for the lower stability relative to CoCl42−.

Research on Thermodynamic Properties of Bioleaching Solution in Lean Nickel-Cobalt Ore by Pitzer - Meissner Model

2015 ◽  
Vol 1092-1093 ◽  
pp. 1455-1459
Author(s):  
Chu Yue Hou ◽  
Gui Ying Zhou ◽  
Jian Kang Wen ◽  
Biao Wu
Keyword(s):  
Thermodynamic Properties ◽  
Activity Coefficient ◽  
Aqueous Solutions ◽  
Activity Coefficients ◽  
Pitzer Model ◽  
Foreign Ions ◽  
Nickel Cobalt

In this paper, we jointly use the Pitzer model and the Meissner model to study thermodynamic laws of bioleaching solution in a lean nickel-cobalt ore in the Jilin Baishan, by using the Pitzer model to calculate activity coefficients of single electrolyte aqueous solutions and the Meissner model to calculate activity coefficients of components in the bioleaching solution. Also we studied the rules of activity coefficient of NiSO4 and CoSO4 in the solution. Results show that when separating and purifying foreign ions from bioleaching solution of the lean nickel-cobalt ore, the descending sequence of their ion concentration’s effect over the solution is Mg2+, Fe3+, Fe2+, Ni2+, Co2+ and Ca2+.

scholarly journals Thermodynamic Properties of Aqueous Sulfuric Acid

2014 ◽  
Vol 59 (8) ◽  
pp. 2389-2407 ◽  
Author(s):  
Hannu Sippola ◽  
Pekka Taskinen
Keyword(s):  
Sulfuric Acid ◽  
Thermodynamic Properties ◽  
Aqueous Sulfuric Acid
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