Development of accurate chemical thermodynamic database for geochemical storage of nuclear waste. Part II: Models for predicting solution properties and solid-liquid equilibrium in binary nitrate systems

The main purpose of this study is to develop new thermodynamic models for solution behavior and solid-liquid equilibrium in 10 nitrate binary systems the type 2–1 (Mg(NO 3 ) 2 -H O, Ca(NO Ba(NO Sr(NO UO (NO O), 3–1 (Cr(NO Al(NO La(NO Lu(NO 4–1 (Th(NO 4 O) from low very high concentration at 25 °C. To construct models, we used different versions standard molality-based Pitzer approach. parameterize all available raw experimental osmotic coefficients data (φ) whole range solutions, up supersaturation zone. predictions developed are excellent agreement with φ-data, recommendations on activity (γ ± solutions concentration. Deliquescence Relative Humidity (DRH), solubility product (as ln K° sp 12 solid phases, precipitating saturated have been calculated. concentration-independent described importance development strategies programs nuclear waste geochemical storage.