Aqueous thorium chloride complexes

Figure VIII-8 Reinterpretation of data reported by [1952WAG/STO] for the extraction of thorium from chloride-perchlorate solutions at / = 4.0 M, using the strict ion interaction approach without chloride complexes. The calculations were performed with the NONLINT-SIT code. The SIT ion-interaction parameters used for these calculations included s(H+Cl) = 0.12 kg-mol s(H+,C10 ) = 0.14 kg-mol s(Th + Cl) = 0.25 kg-moT s(Th +CIO") = 0.70 kg-mol8(Na+ CF) = 0.03 kg-mol e(Na+,C10 ) = 0.01 kg-moF and e(Na, OH ) = 0.04 kg-mol taken from Appendix B (full curve) or the value 8(Th", Cr) = (0.259 + 0.222) kg-mol fitted from the data (dashed curve). Changes in aqueous thorium concentrations as a function of chloride concentrations (a) or in HD (b) as a function of chloride concentrations are depicted and show that the data can be well predicted by the ion-interaction model up to chloride concentrations of about 3.0 m.

This is a detailed study of the extraction equilibria in the toluene-Th(lV)-hydrogen 2-ethylhexyl phosphonate-Cl - NO3 systems. There is no quantitative information on the formation of complexes between thorium and Cf or NOj in the aqueous phase, only a qualitative statement that Th(NOj and Th(NOj )l " complexes are extracted to a much greater extent than the corresponding chloride complexes. 

Thorium has been sorbed on strongly basic anion-exchangers as the nitrate complex most other metals are not retained [15-19]. Other media employed include chloride [20], sulphate [2], thiocyanate [21], and citrate [22]. In numerous cases, mixed aqueous-organic... 

The donor action of [NOs]" as an anionic ligand towards thorium(iv) and uranium(iv) in the presence of trimethylphosphine and tris(dimethylamino)phosphine oxide in aqueous media has been found to be very similar. The larger nitrate ion was observed to form more stable species with thorium than the chloride ion whereas in the uranium(iv) case both complexes formed equally readily. A study of the sulphate complexes of uranium(iv), neptunium(vi) and plutonium(vi) in HCIO4-H2SO4 solution showed the stability constants to follow the order U[Pg.453]

Lead is reported to be almost imique in not forming compounds of this tA pe, basic lead nitrate and chloride being the principal products formed when aqueous hexamethylenetetramine solutions are reacted with lead nitrate and lead chloride, respectively - . Complexes are reported ivith salts of lithium, sodium, potassium, copper,. silver, gold, magnesium, calcium, strontium, barium, zinc, cadmium, mercury, aluminum, titanium, lanthanum, cerium, neodymium, yttrium, erbium, thorium, tin, antimcnj, bismuth, chromium, molybdenum, tungsten, uranium, manganese, iron, cobalt, nickel, platinum, and palladium -... 

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