Effect of metal nitrates on strontium extraction with 4',4''-di-tert-butyl-dicyclohexano-18-crown-6

Main factors influencing efficiency of strontium extraction are the concentration of extracting agent in the organic phase (CCrown) as well as the concentration of nitrate-ions ([NO3-]) and nitric acid ([HNO3]) in aqueous phase. Unfortunately, detailed information describing the effect of foreign ions on the strontium extraction with crown-ethers is not available in literature. A formal analysis, shows that at a certain concentration of the nitric acid and nitrate-ion extraction of strontium from neutral solutions can be more efficient than that from the strongly acidic ones ([HNO3] ≥ 3 mol/l), which are traditionally used for strontium extraction. Results of our experiments presented in the figure below have confirmed this assumption. The effect of lithium, magnesium, aluminum and yttrium nitrates has been studied. (orig.)