The carbonic acid system and calcite solubility in aqueous Na-K-Ca-Mg-Cl-SO[sub 4] solutions from 0 to 90[degrees]C

Journal Article · Sun Aug 01 00:00:00 EDT 1993 · Geochimica et Cosmochimica Acta; (United States)

OSTI ID:6014128

Shiliang, He; Morse, J W ^[1]

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1. Texas A M Univ., College Station (United States)

CO[sub 2] solubility, and the first and second stoichiometric dissociation constants of carbonic acid (K*[sub 1] and K*[sub 2]), have been determined in aqueous solutions containing Cl and SO[sub 4] salts of Na, K, Ca, and Mg over a wide range of ionic strength from 0 to 90[degrees]C at 0.1032 MPa (1 atm) pressure. Activity coefficients for CO[sub 2(aq)], HCO[sub 3][sup [minus]], and CO[sub 3][sup 2[minus]] ions were calculated from m[sub CO[sub 2]], K*[sub 1] and K*[sub 2]. These activity coefficients were then used to derive Pitzer parameters for the interaction between these carbonate species and other ions between 0 and 90[degrees]C. The resulting Pitzer model for the carbonic acid system was verified by its ability to accurately predict experimentally determined calcite solubility in brines from 0 to 90[degrees]C. However, calcite solubility measurements in complex brines initially supersaturated with respect to calcite indicate that Na[sup +], Mg[sup 2+], and SO[sub 4][sup 2[minus]] ions are probably incorporated into calcite lattice and significantly increase calcite solubility in brines. 50 refs., 8 figs., 7 tabs.

• OSTI ID: 6014128
• Journal Information: Geochimica et Cosmochimica Acta; (United States), Vol. 57:15; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
ACID CARBONATES
DISSOCIATION ENERGY
CALCITE
SOLUBILITY
CARBON DIOXIDE
CARBONATES
CARBONIC ACID
CHEMICAL REACTION KINETICS
MATHEMATICAL MODELS
AQUEOUS SOLUTIONS
BRINES
CALCIUM CHLORIDES
CALCIUM SULFATES
POTASSIUM CHLORIDES
POTASSIUM SULFATES
SODIUM CHLORIDES
SODIUM SULFATES
ALKALI METAL COMPOUNDS
ALKALINE EARTH METAL COMPOUNDS
CALCIUM COMPOUNDS
CALCIUM HALIDES
CARBON COMPOUNDS
CARBON OXIDES
CARBONATE MINERALS
CHALCOGENIDES
CHLORIDES
CHLORINE COMPOUNDS
DISPERSIONS
ENERGY
HALIDES
HALOGEN COMPOUNDS
HYDROGEN COMPOUNDS
INORGANIC ACIDS
KINETICS
MINERALS
MIXTURES
OXIDES
OXYGEN COMPOUNDS
POTASSIUM COMPOUNDS
REACTION KINETICS
SODIUM COMPOUNDS
SOLUTIONS
SULFATES
SULFUR COMPOUNDS
540310* - Environment
Aquatic- Basic Studies- (1990-)