Study of deoxidization process of CsI melt by the action of "Zr-Pt" galvanic couple

Abstract

The course of removal of oxide ion admixtures (deoxidization) from molten cesium iodide using galvanic couple zirconium-platinum at 973 K was studied by a potentiometric method using a membrane oxygen electrode Pt(O₂)⁄YSZ (YSZ - yttria stabilized zirconia) as an indicator one for the detection of current and equilibrium concentrations of O₂-. The running of the deoxidization in both cases is subjected to kinetics of 2nd order process with respect to O<m^>2- and the rate constant is as (3.07±0.31)·106 kg·mol⁻¹·min⁻¹·cm⁻² for the galvanic couple. Surface capacity of the galvanic couple with respect to oxide ions was estimated as 7.6·10-4 mol·cm⁻². The destruction and fixation of oxygen-containing admixtures in the case of the galvanic couple occur more intensively that in the case of pure zirconium and Zr-Pt combination is more promising agent for deep purification of growth halide melts.