GAS CHROMATOGRAPHIC EVALUTATION OF EQUILIBRIA IN FUSED SALTS .I. TETRACHLOROALUMINATE AND TETRACHLOROFERRATE SYSTEMS

Gas chromatography has been applied for the first time for the determination of complex stability constants in inorganic fused-salt systems. Specific retention volumes, partition coefficients, and other thermodynamic data for the volatile solutes SbCI3, NbCl5, and TaCl5 in a series of alkali metal tetrachloroaluminate and tetrachloroferrate liquid phases show that complexes formed between the solute and solvent exhibit decreasing stability with change of liquid-phase alkali metal in the order potassium > thallium > sodium > lithium. Variations are due to differences in availability of complexing chloride ion resulting from the equilibrium 2AlCl4 ↔ Al2Cl7- + Cl-. Through measurements of the gas chromatographic partition coefficient of SbCl3 as a function of added excess alkali metal chloride in the tetrachloroaluminate and tetrachloroferrate liquid phases, the following equilibria have been established:[Formula-Ommited]. © 1969, American Chemical Society. All rights reserved.