Rapid separation of VI/VII technetium oxidation states by solvent extraction with iodonitrotetrazolium chloride

Extraction of moderate oxidation state technetium species between 30 % tri-n-butyl phosphate and H2SO4/HNO3

“…Similarly as in the absence of nitric acid, also for H 2 SO 4 /HNO 3 solutions the distribution ratio of technetium was the highest for pertechnetates ( D Tc = 5.47) and decreases to 0.97 for Tc(III), to 0.43 for TcO 2+ and to 0.05 for [Tc 2 O 2 ] 3+ . Obtained results are in line with the literature data [ 5 , 6 ] which report that distribution ratios for technetium at +II or +IV oxidation state are lower than for pertechnetate ions. The distribution ratio obtained for technetium species generated in 4 M H 2 SO 4 at potential 0.55 V was higher than for Tc(III) or Tc(IV).…”

“…This was observed for e.g. Tc(IV) [ 6 ] and Tc(II) [ 7 ] species and for TcO 4 − [ 8 ] also in the absence of the actinides. It was found [ 8 ] that the technetium distribution ratio, D Tc , in TBP (45 %)/kerosene system increases with increasing acidity of the aqueous phase: from 4.5 for 0.5 M H 2 SO 4 to 15.7 for 2 M H 2 SO 4 .…”

“…Generally, technetium ions with lower than +VII oxidation states are weaker extracted into organic phase than pertechnetates [ 6 , 7 , 15 ] although anionic thiocyanate Tc(V) complexes can be extracted with trioctylphosphine oxide or trioctylamine hydrochloride in cyclohexane or 1,2-dichloroethane as was reported by Boyd [ 16 ]. To the best knowledge of the author, no literature date describing the structure of Tc-TBP complexes are available.…”

Liquid-Liquid Extraction-Spectrophotometric Investigations of Three Ternary Complexes of Vanadium(V)

“…17 The objectives of this work were to investigate three LLE systems containing vanadium(V), TAO, tetrazolium salt (TZS; see Table 1), water and chloroform. TZSs are cationic ion-association reagents 18 with resent applications for LLE separation 19 and spectrophotometric determination of metal and nonmetal ions. 20−23 LLE systems involving PAR-TZS or TAR-TZS were systematically investigated in our laboratory and some of these systems were applied for V(V) determination 24 and V(IV)/V(V) speciation.…”

Radiation synthesis of binary poly(ionic liquid) functionalized silica-based materials for selective adsorption of ReO4− as analogue of TcO4− from simulated radioactive wastewater

“…À such as precipitation, extraction, membrane separation and adsorption. [7][8][9][10] By contrast, adsorption is one of the most promising methods for capturing TcO 4 À due to its low cost, simple operation and high efficiency. 11 So far, many materials have been studied for TcO 4 À capture, including inorganic materials, 12 organic materials and novel materials such as metal organic frameworks (MOFs) 13,14 and covalent organic frameworks (COFs).…”