Preparation of ammonium chloroplatinate by a precipitation stripping of Pt(IV)-loaded alamine 336 or TBP

摘要

The possibility of preparing ammoniumchloroplatinate powders by precipitation stripping from Pt-loadedAlmaine 336 or TBP was investigated experimentally. A similarexamination was done for the precipitation stripping of Pd(II).Furthermore, the possible separation of Pt(IV) from Alamine 336,loaded with both Pt(IV) and Pd(II), was studied. Precipitationstripping of (NH4)2PtCl6 from Pt(IV)-loaded Alamine 336 waspossible using an aqueous NH3 solution and aqueous mixedsolutions of NH3-NH4Cl or NH4Cl-HclO4. It was found that theuse of 0.2kmol m-3 HclO4-2 kmol m-3 NH4Cl as a strippingsolution was most effective. The precipitation of (NH4)2PtCl6from Pt(IV)-loaded TBP was almost completely achieved using anaqueous NH3 solution concentrated above 2 kmol m-3. Pt(IV) canbe efficiently separated as (NH4)2PtCl6 precipitates from bothPt(IV) and Pd(II)-loaded Alamine 336, using 0.2 kmol m-3HclO4-4 k mol m-3 NH4Cl, with soluble Pd(II) remaining in boththe aqueous and organic phases.