ELECTRODE-REACTIONS OF ELECTROCHEMICALLY GENERATED SELENIUM SPECIES IN BASIC ALCL3-NACL MELTS

The electrochemical reactions of selenium species in basic AlCl3-NaCl melts were studied using various voltammetric techniques. The electroc hemical measurements were carried out in a basic melt containing diffe rent oxidation states of selenium, which were prepared by electrochemi cally oxidizing elemental selenium. The results obtained in this study present a new interpretation for the reaction mechanism of the oxidat ion of elemental selenium to tetravalent selenium, which proceeds via at least four electrochemical steps involving the following intermedia tes, Se-8(2+), Se-4(2+), Se-2(2+) and Se2+. It is also confirmed that the reaction sequence is in good agreement with the results obtained b y the thermodynamic analysis of emf of a Na/SeCl4 cell in our previous study.