Solvent Extraction of Thallium(I) with Chelating Extractants Coordinating through Oxygen Atoms

Abstract

The solvent extraction of thallium(I) in aqueous 0.1 mol dm−3 sodium nitrate solutions with seven chelating extractants [(HA), 1-phenyl-1,3-butanedione (Hbza); 1,3-diphenyl-1,3-propanedione (Hdbm); 4,4,4-trifluoro-1-phenyl-1,3-butanedione (Hbfa); 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione (Htta); 2-hydroxy-4-isopropyl-2,4,6-cycloheptatrien-1-one (Hipt); 5,7-dichloro-8-quinolinol (Hdcox); and 1,1,1-trifluoro-4-mercapto-4-(2-thienyl)-3-buten-2-one (Hstta)] into chloroform was studied in the absence and presence of tetrabutylammonium ions (tba+) or trioctylphosphine oxide (TOPO). The TlA type chelates were extracted, and, except for Hbza and Hdbm, tba+TlA2−-type ternary complexes were extracted. However, the extraction of adduct chelates with TOPO was not obtained. A comparison of the stability, liquid–liquid partition, and acceptability of a further ligand in the organic phase was made with TlA, AgA, and LiA when A− was 1,1,1-trifuluoro-3-(2-thienyl)-2,4-butanedionate ion (tta−) and the ligand was TOPO or tta−.

Solvent Extraction of Silver(I) as Anionic Metal Complexes with 2-Thenoyltrifluoroacetone and 4-Isopropyltropolone into Chloroform in the Presence of Tetrabutylammonium Ions

“…The association of an uncharged complex of univalent metal ions with tba+tta in chloroform is reported with lithium(I) and thallium(I) in ref. 12, as listed in Table 3. Such association constants are also reported with divalent metal ions in ref.…”

“…The very large difference in the value of Korg of Ag(tta) from that of Tl(tta) should be due to the fact that Tl(tta) is an especially poor acceptor of any ligand, as can be seen from ref. 12.…”

“…12 The aqueous phase was a 0.1 mol dm-3 sodium nitrate solution containing none or a certain amount of tba+N03-. The hydrogen-ion concentration was adjusted by using 0.01 mol dm 3 or 0.1 mol dm 3 NaOH.…”

“…Figure 1 also gives the extraction with Htta in the initial presence of 1X10-3 mol dm 3 tbat The extraction was very much enhanced by the tbat The data were analyzed on the basis of Eq. (12). The values of the obtained constants are given in Table 2.…”

Solvent Extraction of Copper(I) Anionic Thiocyanate Complex into Chloroform and 4-Methyl-2-pentanone as Ion-Pairs with Tetrabutylammonium

“…Furthermore, it was also found that copper(I) thiocyanate complexes were extracted into MIBK when a certain amount of reducing agent, ascorbic acid, was added.2,3 The extraction was quantitative even when the thiocyanate concentration was 1X103 mol dm 3 and under these conditions only silver(I) and mercury(II) were extractable to an appreciable amount, among several metal ions.l3 An addition of 1X103 -mol dm-3 tetrabutylammonium (tba+) made the extraction of copper(I) into MIBK much more effective. 3 The results obtained in these studies indicate that a good extraction of copper as thiocyanate should be achieved when it was reduced to copper(I) and bulky cations such as tba+ are present. The present study was made in order to determine the conditions for an effective solvent extraction of copper from dilute thiocyanate solutions containing ascorbic acid, from which the extraction of several other metal ions was slight.…”