Extractive Separation of Aluminum(III), Gallium(III) and Indium(III) Using Bis(1, 1, 3, 3-tetramethylbutyl)phosphinic Acid and Its Sulfur Analogues

抄録

The extraction behavior of Al(III), Ga(III) and In(III) was investigated using bis(1, 1, 3, 3-tetramethylbutyl)phosphinic acid (MBP) and its sulfur analogues, bis(1, 1, 3, 3-tetramethylbutyl) monothiophosphinic acid (MTP) and bis(1, 1, 3, 3-tetramethylbutyl)dithiophosphinic acid (DTP) as extractants. A typical chelate extraction behavior was observed in these extraction systems in the pH range examined. The degree of extraction was in the order of In(III)>Ga(III)>Al(III). Moreover, the ability of extractants for mutual separation of these metals from one another decreased in the following order: DTP>MTP>MBP. The quantitative mutual separation of these metals can be achieved using DTP/hexane with single extraction. In the higher HCl concentration range, however, slight extraction of Ga(III) and In(III) was observed; this is due to the extraction of GaCl₄^- and InCl₄^- pairing with the protonated extractants.