Technetium sulfide - formation kinetics, structure and particle speciation

摘要

Technetium sulfide formation kinetics was studied in the pH range 8-12 in presence of Na2S and phosphate buffer solution. The conditions for separation of Tc sulfide micro and nanoparticles were found with ultra-microcentifugation and the values of Tc sulfide solubility were demonstrated to be dependent on the Na2S concentration as C(Tc3S10+x) = -9 x 10(-5) ln [Na2S]-2 x 10(-5) M. The composition of Tc sulfide precipitate was elucidated with EXAFS, RBS and chemical analyses as Tc3S10+x or [Tc-3(mu(3)-S)(S-2)(3)(S-2)(3/3)](n) in agreement with recent Lukens data.