Impregnated resins containing di-(2-ethylhexyl) thiophosphoric acid for the extraction of palladium(II). II. Selective palladium(II) recovery from hydrochloric acid solutions

The extraction of Pd(II) from HCl solutions by impregnated resins containin g di-(2-ethylhexyl) thiophosphoric acid (DEHTPA or HL) on the Amberlite XAD 2 polymeric support has been studied. Graphical and computer analysis with the program LETAGROP-DISTR demonstrated that the Pd(II) extraction can be e xplained by the formation of metal complexes in the resin phase having the composition PdL2(HL)(2). DEHTPA/XAD2 resins extracted. Pd(II) in the presen ce of other metals: Pt(IV), Rh(III), Cu(II), Fe(III) as well as Zn(II). The stripping of Pd(II) loaded on the organic phase and the lifetime of the re sins were also investigated.