Thermodynamics Research Center / ThermoML | Fluid Phase Equilibria

Oxoacidity scale of molten ionic chlorides and bromides

Cherginets, V. L.[Victor L.], Rebrova, T. P.[Tatyana P.], Naumenko, V. A.[Vyacheslav A.]
Fluid Phase Equilib. 2015, 401, 77-81
ABSTRACT
Determination of NiO and PbO solubilities in molten BaBr2-KBr (0.505:0.495) eutectic at 973 K (of pK_s,NiO = 8.06 +/- 0.2 and pK_s,PbO = 4.04 +/- 0.2, molality scale) allowed completing systematic oxide solubility studies in molten ionic bromides. On the basis of the obtained and literature data the acidity scale for chloride and bromide melts (KX-NaX to BaX2-KX to KX-LiX sequences, X = Cl, Br) at 973 K was built on the basis of primary medium effects (estimated as oxobasicity indices). The oxoacidic properties of chloride and bromide melts with similar cation composition are close, although the acidity of bromide analogs is always somewhat weaker. The obtained information permits to predict e.g., limits of halide melt purification by precipitating deoxidization or carbohalogenation methods.
Compounds
# Formula Name
1 OPb lead(2+) oxide
2 NiO nickel(II) oxide
3 BaBr2 barium bromide (BaBr2)
4 BrK potassium bromide
Datasets
The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type Compound-# Property Variable Constraint Phase Method #Points
  • POMD
  • 1
  • 4
  • 3
  • Mole fraction - 1 ; Liquid mixture 1
  • Mole fraction - 3; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • potentiometry
  • 1
  • POMD
  • 2
  • 4
  • 3
  • Mole fraction - 2 ; Liquid mixture 1
  • Mole fraction - 3; Liquid mixture 1
  • Pressure, kPa; Liquid mixture 1
  • Temperature, K; Liquid mixture 1
  • Liquid mixture 1
  • Liquid mixture 2
  • potentiometry
  • 1