Photochemical behaviour of Tc2OCl10 4– and TcnOy 4n–2y+ in chloride media

Abstract

Summary The stabilities of the technetium polymers Tc2OCl10 4− and TcnOy 4n−2y+ have been studied under light irradiation in 3 M chloride media with a pH range from 0 to 1.3. It has been shown that under irradiation, Tc2OCl10 4− is not stable and undergoes dissociation to TcCl5(H2O)- at pH = 0 and pH = 0.3. At pH = 1, irradiation of Tc2OCl10 4− leads to a stationary state involving TcCl5(H2O)- and Tc2OCl10 4−. At pH = 1.3, TcnOy 4n−2 y+ remains stable under irradiation. Under light irradiation, the predominance diagram of Tc(IV) species obtained from Tc2OCl10 4− aquation in a pH range from 0 to 1 is drawn. The chemical behaviour of Tc2OCl10 4− and the influence of the light on the condensation of Tc(IV) and solubility of TcO2· x H2O are discussed.