Effect of Diluents on The Synergistic Solvent Extraction and Separation of Trivalent Lanthanoids With 4-Benzoyl-3-Phenyl-5-Isoxazolone and tert-Butylcalix[4]Arene Tetrakis(N,N-Dimethyl Acetamide) and Structural Study of Gd(III) Solid Complex By IR and NMR

The solvent extraction of 14 lanthanoid(III) ions from a chloride medium with acidic chelating extractant 4-benzoyl-3-phenyl-5-isoxazolone (HPBI) and tert-butylcalix[4]arene tetrakis(N,N-dimethylacetamide) (S) as a synergistic agent in C6H6 has been studied. In all cases, Ln(III) ions were extracted as Ln(PBI)3·S species. Positive values of the synergistic coefficients show that all lanthanoids were extracted synergistically upon the addition of compound S to the chelating extractant. The values of the equilibrium constant and the separation factors were calculated. The synergistic solvent extraction of five selected lanthanoid ions (La3+, Nd3+, Eu3+, Ho3+, and Lu3+) with a mixture of HPBI and S from a perchlorate medium in other diluents such as CHCl3, C2H4Cl2, and CCl4 has been studied too. It was found that the values of the equilibrium constant increased in the order CHCl3 < C2H4Cl2 < CCl4. The effect of the diluents on the metal extraction and separation has been discussed. A solid complex of Gd(III) with HPBI and S was synthesized. The composition of the complex was determined as Gd(PBI)3·S using elemental analysis, IR, and 1H NMR data.