Etude critique des réactifs des cations. 7. Réactifs des cations du thorium

Inorganic Gravimetric Analysis

“…THORIUM Wenger and Duckert (345) examined the efficiency of known réagents for the determination and detection of thorium. Out of some 25 reagents four only were recommended: (1) thallous nitrate with ammonium carbonate gave characteristic crystals with thorium or with U02 ++; (2) oxine, which is useful for spot testing of U02 + +, Zr + + + +, as well as thorium; (3) hydrogen peroxide, with sodium thiosulfate and barium chloride, which reacts with thorium, titanium, vanadium, molybdenum, tungsten, and zirconium; and (4) benzenearsonic acid which reacts with thorium, Ce + + + +, and Zr + + + +.…”

The Analytical Aspects of Thorium Chemistry.

“…(115) may perhaps be of use in the detection of thorium in the presence of the rare earth elements, since the corresponding compounds of the latter materials are uniformly yellow regardless of conditions (92). Useful summaries of the applicabilities and limitations of these colorimetric tests are given by van Nieuwenburg et al (241) and by Wenger and Duckert (247).…”

“…Ultimately, the mixed oxalates are converted to nitrates either directly by action of fuming nitric acid or indirectly by ignition to oxides and dissolution in the acid, excess acid being removed by evaporation. The majority of the methods listed by van Nieuwenburg et al (241) and by Wenger and Duckert (247) are applicable to such solutions.…”