Distribution Studies of Actinides Using a Tetradentate Extractant, 4,4′-Nonanedioyl-Bis(2,4-Dihydro-5-Methyl-2-Phenyl-3H-Pyrazol-3-One)

Solid‐Liquid Extraction of Lanthanum(III), Europium(III), and Lutetium(III) by Acyl‐Hydroxypyrazoles Entrapped in Mesostructured Silica

“…Compared with the currently used lipophilic substituted acetylacetones (typically pK a ¼ 6.25), their higher acidity pK a (2.6 -4.0) allows extractions at lower pH's. Particularly, they form stable extractable complexes, in acidic solutions, with lanthanoids ions (1 -3) and actinoids ions (4,5). a,v-bis(5-hydroxy-pyrazol-4-oyl) alcanes, HL-n-LH, are better extractants than the corresponding 4-acyl-5-hydroxypyrazoles in solvent extraction.…”

Solvent extraction of lanthanum(III), europium(III) and lutetium(III) by bis(4-acyl-5-hydroxypyrazoles) derivatives

“…Dong et al [9] were the first to use HL-n-LH of different polymethylene chain length in the extraction of UO 2 2+ in chloroform: they demonstrated a higher efficiency of extraction by HL-n-LH than by their parent compounds 4-acyl-5-hydroxypyrazoles (HL) which was later confirmed and explained by a higher lipophilicity of the former ones [10,11]. The extraction of transition metals (Cu 2+ , Zn 2+ , Co 2+ and In 3+ ) by these ligands were explored by our group [12].…”

“…The extraction of transition metals (Cu 2+ , Zn 2+ , Co 2+ and In 3+ ) by these ligands were explored by our group [12]. Miyazaki et al [13] studied the effect of the polymethylene chain length (n = 0-8, 10,20) on the extraction of copper(II) by HL-n-LH. They found that the extracted species vary with "n": Cu(L-n-L) for n = 8, 10, 20 and Cu(L-n-LH) 2 or Cu 2 (L-n-L) 2 for n = 1-7.…”

“…Therefore,they act as biscoordinating ligands in 1:2 complexes or as bridging tetracoordinating ligands in 2:2 complexes. The bis(acyl-hydroxypyrazoles) HL-n-LH (n = 0, 1-8, 10, 20, 22) have been used for the liquid-liquid extraction of Am 3+ [10], Th 4+ [10,15], Cu 2+ [13,16], Ni 2+ [17] Zn 2+ [17,18], Hg 2+ [19], UO 2 2+ [9,10,15,[19][20][21][22], VO 2 2+ [21,22], Be 2+ [23], Sc 3+ [23], Y 3+ [23], In 3+ [24], La 3+ [25,26] or lanthanides(III) [10,[27][28][29][30][31]. Takeishi et al [11] postulated a procedure for the successive separation of the actinides in nitric acid medium using HL-8-LH.…”

Synergistic extraction of lanthanoids with heterocyclic β-ketoenols and 2,4,6-tri(2-pyridyl)-1,3,5-triazine, TPTZPart II. Extraction of La(III), Eu(III) and Lu(III) with a bis(4-acyl-5-hydroxypyrazole) and TPTZ

“…Like their parent compounds, their exchangeable acidic protons and hard donor oxygen atoms allow them to strongly interact with metal ions such as alkaline earths [1,2], lanthanoids [3][4][5][6] and actinoids [7,8]. Moreover, their structure sometimes induces unexpected complexation and extraction selectivities, while generally they are better extractants than their parent compounds, thanks to their higher lipophilicity [7,9]. Therefore, since 1980, about 200 articles have dealt with the formation of complexes between HLn-LH and diverse hard metal cations.…”