Synergistic extraction of Eu(III) with mixture of picrolonic acid and neutral organophosphorous extractants

Liquid–liquid extraction of Eu(lll) using synergic mixture of 1-phenyl-3-methyl-4-trifluoroacetyl-2-pyrazolin-5-one and crown ethers

“…In continuation to our earlier work [10,11,13,[17][18][19][20][21][22][27][28][29], another schematic study consisting of 1-phenyl-3-methyl-4-trifluoroacetyl-2-pyrazolin-5-one (HPMTFP) in dichloromethane (DCM) as single extractant and then with synergic mixture of HPMTFP and crown ethers (B-15C-5, 18-C-6 and 15-C-5) in DCM for the extraction of europium(III) is presented. The optimum conditions for the extraction of europium using synergic mixture of HPMTFP and crown ethers was also studied.…”

“…The acidic ligand HPMTFP form aquo complex with Eu(III), so the extraction coefficient is very low and the lowering of this extraction coefficient is due to the presence of water molecules the complex showed great solubility in water than in non-polar solvent. The formation of such kind of aqua complexes for the rare earth metals is also cited in the literature [18]. Addition of crown ethers replace water molecules from aquo complex in a stepwise manner that increase the extraction of adduct in the organic phase.…”

“…A number of researchers have focused on synergic extraction of rare earth elements by using mixture of different extracting agents such as hydrogen dicarboylcobaltate with dibutyl diethylcarbamoyl methylene phosphonate [12], picrolonic acid with methyl isobutyl ketone [13], nitric acid with 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester [14], thenoyltrifluoroacetone with trioctylphosphine oxide, diphenyl sulphonide and tributylphosphate [15], crown ethers and picrate ions [16], picrolonic acid with tributylphosphineoxide [17], picrolonic acid-trioctylphosphine oxide, triphenylphosphine oxide and and tributylphosphate, [18] picrolonic acid-B15C5 [19], di-n-butylsulfoxide-Cyanex-272 [20], 3-Methyl-1-phenyl-4-trifluoroacetyl-2-pyrazolin-5-one (HPMTFP) and tribenzylamine and 2-thenoyl-trifluoroacetone with tribenzylamine [21,22]. However, due to some shortcomings, such as co-extraction, poor selectivity and third phase formation there is still a need of more specific extracting agents for the extraction of europium.…”