Technetium Behavior in Nitric Acid Solution Containing Hydrazine Nitrate and Multi-Charged Metal Cations (Th and Zr)
Technetium (VII) reduction kinetics was investigated by spectrophotometric method in Tc(VII) - Th(IV)/Zr(IV) - N <sub>2</sub>H <sub>5</sub>NO <sub>3</sub> - HNO <sub>3</sub> system; reaction rate constants and all reaction stage sequences were calculated. For the first time a new chemical form of technetium (V) was discovered and described, that arose at its reduction by hydrazine nitrate in HNO <sub>3</sub> solutions. It was demonstrated that thorium (IV) and to a greater extend zirconium (IV) produced stabilizing effect on above mentioned previously unknown technetium (V) complex. Complex composition Тс : Zr(Th) was determined as 2:1. On base of derived information the simplest possible complex structure was suggested.