The solubility and activity coefficient of oxygen in salt solutions and brines
- Univ. of East Anglia, Norwich (England)
Molal oxygen activity coefficients ({gamma}{sub o{sub 2}}) in aqueous salt solutions from 0-100{degree}C have been calculated from O{sub 2} solubility data and established Henry's law constants. Pitzer specific interaction model parameters {lambda}{sub o{sub 2{sup c}}}, {lambda}{sub o{sub 2{sup a}}}, and {zeta}{sub o{sub 2{sup ca}}} have been determined for the following ions: H{sup +}, NH{sub 4}{sup +}, Li{sup +}, Na{sup +}, Rb{sup +}, Cs{sup +}, Mg{sup 2+}, Ca{sup 2+}, Ba{sup 2+}, Al{sup 3+}, OH{sup {minus}}, Cl{sup {minus}}, Br{sup {minus}}, I{sup {minus}}, NO{sub 3}{sup {minus}}, SO{sub 3}{sup {minus}}, SO{sub 4}{sup 2{minus}}, HCO{sub 3}{sup {minus}}, CO{sub 3}{sup 2{minus}}, and PO{sub 4}{sup 3{minus}}. Results confirm that the effect of individual ions on 1n ({gamma}{sub o{sub 2}}) is additive. Model calculations of {gamma}{sub o{sub 2}} in seawater agree with experimentally derived values at normal salinities to within 0.2% at 298 K and 0.65% at 273 K. Additional data for brines of seawater composition enable the model to be used to represent {gamma}{sub o{sub 2}} empirically to a salinity of 255 S{per thousand}. The model has thus far only been parameterized from measurements for single salt solutions. Comparisons with experimental data for brines suggest that additional model parameters, obtained from ternary solution data, will be required for accurate representation of {gamma}{sub o{sub 2}} in mixed salt solutions above about 5 mol kg{sup {minus}1} total ion concentration.
- OSTI ID:
- 5950141
- Journal Information:
- Geochimica et Cosmochimica Acta; (USA), Journal Name: Geochimica et Cosmochimica Acta; (USA) Vol. 54:12; ISSN GCACA; ISSN 0016-7037
- Country of Publication:
- United States
- Language:
- English
Similar Records
Experimental studies of aluminum solubility and speciation in brines
Experimental studies of aluminum solubility and speciation in brines