VOLUMETRIC-ANALYSIS FOR THE CONTROL OF BI SMUTH AND TELLURIUM SOLUTIONS AND ALLOYS

Potentiometric titrations in nitric medium for the control of bismuth and tellurium content are described. Bismuth +III determination is obt ained by complexation with EDTA, and tellurium +IV by oxidation with a chromium +VI solution. These simple and sensitive methods permit the control of electrolyte solutions used for the electrosynthesis of bism uth telluride alloys. These techniques are applied to stoichiometry de termination of Bi-Te alloys after dissolution and results are in good agreement with those found by a microprobe analyser.