Zur Polarographie des Technetiums 1 : Gleichstrom- und Wechselstrom- polarographische Untersuchungen an Pertechnetatlösungen

Neutral and alkaline solutions of $K^{99}TcO_{4}$ in the conccntration range of $10^{-3}$ to $10^{-4}$ M have been investigated polarographically with direct and alternating current. Four steps and waves respectively have been observed. The first two steps of $E_\frac{1}{2} \backsimeq$ ~ -o.8 V and $\backsimeq$ -1.1 V correspond to electron transitions n $\backsimeq$ 2 and $\backsimeq$ 3, whereas the third and fourth steps are influenced by catalytic effects. lt may be specially pointed out that reduction first to Tc(V) takes place not only in alkaline but also in neutral solution. Alternating current efficiencies of 70-90% for the wave $E_{8}$ $\backsimeq$ -0.8 V were obtained as a function of the type and concentration of the supporting electrolyte. From this follows the possibility of a. c. polarographic determination of technetium which is advantageous on account of its higher separation capacity in comparison to the direct current polarographic methods