Pitzer, ion interaction

K. S. Pitzer, Ion interaction approach. In Activity Coefficients in Electrolyte Solutions (R. M. Pytkowicz, Ed.), pp. 157-208. CRC Press, Boca Raton, Florida, 1979 K. S. Pitzer and J. J. Kim, Thermodynamics of electrolytes. IV. Activity and osmotic coefficients for mixed electrolytes. J. Am. Chem. Soc. 96, 5701-5707 (1974) and earlier articles cited. 

K. S. Pitzer, Ion Interaction Approach Theory and Data Correlation , Chapter 3 of Activity Coefficients in Electrolyte Solutions, 2nd Edition, K. S. Pitzer, Editor, CRC Press, Boca Raton, 1991. Parameters for many electrolytes are summarized in this reference. The equations and parameters can also be found in K. S. Pitzer, Thermodynamics, Third Edition, McGraw-Hill, Inc., New York, 1995. 

Because of the high ionic strength of the brines, the calculations were carried out using a Pitzer ion interaction model (US DOE, 1996) for the activity coefficients of the aqueous species (Pitzer, 1987, 2000). Pitzer parameters for the dominant non-radioactive species present in WIPP brines are summarized in Harvie and Weare (1980), Harvie et al. (1984), Felmy and Weare (1986), and Pitzer (1987, 2000). For the actinide species, the Pitzer parameters that were used are summarized in the WIPP Compliance Certification Application (CCA) (US DOE, 1996). Actinide interactions with the inorganic ions H, Na, K, Mg, CU, and HCO /COa were considered. 

Christov calculated the parameters in the Pitzer ion interaction model from isopiestie measurements at 298.15 K by Ojkova and Staneva [890JK/STA]. This reference contains (interpolated) osmotic coefficients of zinc, magnesium, cobalt, and nickel selenate solutions from 0.1 mol-kg to saturated solution. Sodium chloride standards were used and the agreement between duplicate determinations was 0.2% or better. 

The osmotic coefficients were used to find the parameters in the Pitzer ion interaction model. These parameters (see Table A-121) were then employed to find the activity coefficients in saturated solution. 

The second data file read by PHRQPITZ (PITZER.DATA) contains values of the Pitzer ion interaction parameters C, 6. A, including a limited amount of... 

Because in the west of China some salt lake brines contain abundant boron and lithium, in which solute-solvent and solute-solute interactions are complex, studies on the ihermochemical properties for the systems related with the brines are essential to understand the effects of temperature on excess free energies and solubility, and to build a thermodynamic model that can be applied for prediction of the properties. Yin et al. [43] measured the enthalpies of dilution for aqueous Li2B407 solutions from 0.0212 to 2.1530 mol/kg at 298.15 K. The relative apparent molar enthalpies and relative partial molar enthalpies of the solvent and solute were also calculated, and the thermodynamic properties of the complex aqueous solutions were represented by a modified Pitzer ion-interaction model. 

Figure 1. Experimental and calculated solubiliti ofSr(OH) 8H20 in NaOK Patterned line represents calculations with Sr OH interactions described solely with the use ofPitzer s form of the extended Debye-HOckel equation. Solid line represents the calculations of our final thermodynamic model, which includes values for the Pitzer ion interaction parameters. Total concentrations in units of molarity. From (3).

This section presents, in Tables A-I and A-II, a conq>lete summary of the thermodynamic data for the Na-Sr-Ca-0H-C03-N03-EDTA-HEDTA-H20 system. The tenq>erature dependent parameters for the Pitzer ion-interaction parameters were fit to an equation of tiie foma,... 

Table A-I. Parameters for the Temperature Dependent Expression (Eq Al) for the Pitzer Ion-Interaction Parameters for the Na-Sr-Ca-OH-COa-NOs- EDTA-HEDTA-H2O System Continued on next page.

Felmy et al, (18) investigated foe solubility of Pu(OH)3 under reducing conditions in deioni water and brine solution. They deriv a much lower solubility product (log K = -26.2) (see Table I) than foe value (log K = -19.6) reported in foe literature (iP). However, foe solubility in brines [I 6 2Uid I - 10] was found to be larger than foat in deionized (I = 0) waters. The solubility of Pu(OH)3 in brines was accurately predicted with foe Pitzer ion-interaction model using only foe parameters for binary interactions between Pu and Cl". 

As to any electrolyte, its thermodynamic prosperity varied from weak solution to high concentration could be calculated through 3 or 4 Pitzer parameters. Pitzer ion-interaction model and its extended HW model of aqueous electrolyte solution can be briefly introduced in the following (Pitzer, 1975, 1977, 2000 Harvie Wear, 1980 Harvie et al, 1984 Kim Frederich, 1988a-b). 

On Pitzer ion-interaction model and its extended HW model, a numbers of papers were successfully utilized to predict the solubility behaviors of natural water systems, salt-water... 

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