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

Abstract

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−.