Pitzer ion-interaction parameters for Fe(II) and Fe(III) in the quinary {Na+K+Mg+Cl+SO4+H2O} system at T=298.15 K

Thermodynamic model for solution behavior and solid-liquid equilibrium in Na-Al(III)-Fe(III)-Cr(III)-Cl-H2O system at 25°C

“…Our preliminary modeling study on the development of model for corresponding sulfate system Na-Al-SO4-H2O shows that θ(Na,Al) parameter from [28] can not fit well the solubility data in this ternary. In a series of papers Christov [14], developed a solid-liquid equilibrium model, which includes all ternary subsystems within K-Mg-Al-Cl-SO4-H2O, Na-K-NH4-Al-Cr-SO4-H2O [15][16][17] and Na-K-Mg-Fe(III)-Cl-SO4-H2O [21] systems. The author found that for all considered ternary chloride (1-1)+(3-1) and (1-2)+(3-2) sulfate mixtures a θ(Na,M(III)) value equals to (-0.07) gives a very good agreement between experimental solubility data in mixed ternary and quaternary systems, and model predictions.…”

“…The interaction parameters for the binary Fe(III)-Cl system are determined by numerous authors [21,[31][32][33][34][35]. André et al [35], presented a large review of concentration range of application of the existing sets of interaction parameters.…”

“…Consequently, André et al [35] proposed the estimation of a new set of parameters for the binary FeCl3-H2O system using all available experimental activity data given in [27,36,37]. Following Tanaka et al [32] and [14][15][16][17]19,21], a four-parameter approach (β 0 , β 1 , β 2 , and C φ ) is applied for this binary, without considering any complex species in solution. The resulting parameterization gives a good agreement with water activity values up to 16 mol.kg -1 , widely over the solubility of FeCl3, 6H2O(s) (m(sat) (FeCl3, 6H2O(s)) = 6.2 mol.kg -1 ).…”

“…Therefore, in construction of mixing Na-Fe(III)-Cl-H2O model we used our previously evaluated FeCl3-H2O binary parameters from [35]. The solubility product (K o sp) value for FeCl3, 6H2O(s) is taken from Thermoddem database [38] and it is very close to those determinated by [21].…”

“…This is why a permanent updating work must be done in order to increase their applicability, and consequently the quality of predicted results. This paper continues our series () concerning parameterization of Pitzer approach based comprehensive models which can assist in the development of a complex thermodynamic database that can accurately predict the chemical behavior of aluminium Al 3+ [10][11][12][13][14][15][16][17], chromate (CrO4) [18], dichromate (Cr2O7) [19,20], and Iron (as Fe 2+ [21], and Fe 3+ [21,35] solution species and minerals in a sea-type natural fluid systems. The main objective of this study is the development of a high accuracy thermodynamic model for solution behavior, and highly soluble M(III)Cl3(s) (M= Al, Fe, Cr) minerals solubility in Na-Al(III)-Cr(III)-Fe(III)-Cl-H2O system at 25°C.…”