RES³T - Rossendorf Expert System for Surface and Sorption Thermodynamics

Show Detailed Complexation Query Results


Surface Complex Formation Data:

Mineral: Bentonite
Reference: TOFHH94
SCM Type: CC - Constant Capacitance
Ligand: NpO2<1+> - neptunyl(V)
Site Type: »Al-OH
Equation: »Al-OH + NpO2<1+> + 3 CO3<2-> + H<1+>  ⇔  »Al-OH2-NpO2(CO3)3<4->
LogK: 37.1         LogK2.31 nm−2 (SSD-normalized):   40.45
Experiment: Batch Sorption Experiments
Ionic Strength:
Temperature: 343.0 K
Solid/Liquid Ratio: 10.0 g/L
pH Range: 5 - 12
Fit Method:
Comment: 70 °C; assumed that only the clay mineral, montmorillonite, contributes to Np sorption; logK(int): calculated by multiplying the stability constants of the corresponding aqueous complexes to Ks; 60 Bq/ml;
FIT Method: GESPER (modified version of the CHEMTRN code);
!! 2 SSA values measured (BET, EGME) --> not clear which one was used for modelling --> here BET SSA is linked with the modelling results;
original equation in the study: »Al-OH + NpO2(CO3)3<5-> + H<1+> = »Al-OH2-NpO2(CO3)3<4->, logK = 31.60 (NEA-TDB: NpO2<1+> + 3CO3<2-> = NpO2(CO3)3<5->, logK = 5.500)
 
1 data sets were retrieved