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The solvent extraction of thallium(I) with dibenzo-18-crown-6 (DBC) as the picrate into chloroform and benzene was measured at 25 °C. The extraction was nearly the same as that of potassium(I) and much better than rubidium(I); this tendency was mainly attributed to the difference in the stability of the DBC complexes in the aqueous phase. Thallium(III) was extracted only poorly.
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Sekine et al. (1978) studied this question.
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