Occlusion and ion exchange in the molten (lithium chloride-potassium chloride-alkali metal chloride) salt + zeolite 4A system with alkali metal chlorides of sodium, rubidium, and cesium.
Interaction between molten salts of the type LiCl-KCl-MeCl (Me = Na, Rb, Cs, x{sub MeCl} = 0 to 0.5, x{sub KCl}/x{sub LiCl} = 0.69) and zeolite 4A have been studied at 823 K. The main interactions between these salts and zeolite are molten salt occlusion to form salt-loaded zeolite and ion exchange between the molten salt and salt-loaded zeolite. No chemical reaction has been observed. The extent of occlusion is a function of the concentration of MeCl in the zeolite and is equal to 11{+-}1 Cl{sup -} per zeolite unit cell, (AlSiO{sub 4}){sub 12}, at infinite MeCl dilution. The ion-exchange mole fraction equilibrium constants (separation factors) with respect to Li are decreasing functions of concentration of MeCl in the zeolite. At infinite MeCl dilution, they are equal to 0.84, 0.87, and 2.31 for NaCl, RbCl, and CsCl, respectively, and increase in the order Na<Rb<Cs at identical MeCl concentrations. The standard ion-exchange chemical potentials are equal to -(0.0{+-}0.5) kJ{center_dot}mol{sup -1}, -(0.4{+-}0.3) kJ{center_dot}mol{sup -1}, and -(6.5{+-}.5) kJ{center_dot}mol{sup -1} for Na{sup -}, Rb{sup -1}, and Cs{sup +}, respectively.
- Research Organization:
- Argonne National Lab. (ANL), Argonne, IL (United States)
- Sponsoring Organization:
- NE
- DOE Contract Number:
- DE-AC02-06CH11357
- OSTI ID:
- 943218
- Report Number(s):
- ANL/CMT/JA-38390; TRN: US200916%%600
- Journal Information:
- Metall. Mater. Trans. B, Vol. 32, Issue 3 ; Jun. 2001; ISSN 1073-5615
- Country of Publication:
- United States
- Language:
- ENGLISH
Similar Records
Equilibrium Model for Ion Exchange Between Multivalent Cations and Zeolite-A in a Molten Salt
Conditioning of Waste LiCl Salt from Pyrochemical Process Using Zeolite A