Extração liquido-liquido por fase unica : sistema agua-etanol-metilisobutilcetona no estudo da separação de Fe, Co, Ni, Cu e Pb com tenoiltrifluoroacetona

AUTOR(ES)
DATA DE PUBLICAÇÃO

1978

RESUMO

The behavior of the versatile organic solvent methylisobutylketone (MIBK) is studied with respect to use in liquid-liquid Single-Phase extraction employing the system MIBK-ethanol. The metal ion complexas present in the single phase system (water-MIBK-ethanol), may be extracted into the organic phase when an excess of water is added breaking the system down into two imiscible liquid layers. Thenoyltrifluoroacetone (TTA) was used to study the camplexation and the extraction of several metal ions, Fe(III), Co(II), Ni(II), Cu(II) and Pb(II). All these metal ions are rapidly and quantitatively extracted from weakly alkaline medium, even for TTA concentrations in the Single-Phase of the arder of 10 M. In moderately acid medium only Fe(III) is completely extracted; Cu(II) extracts partially and the other metal ions are not extracted. The complete separation of Fe(III) from quantities up to a factor of 10 in excess of either Co(II), Ni(II) or Pb(II) was obtained; these separations are not easily obtained by conventional liquid-liquid extraction with TTA. Also studied was the direct determination of Ni(II) and Pb(II) in the organic phase, after extraction, by atomic absorption spectrophotometry. A partial hydrolysis of Fe(III) in the Single Phase, which retards its complexation with TTA, was carefully studied, and a modification in the preparation of the single-phase was introduced, in arder to avoid this draw back in the technique.

ASSUNTO(S)

extração (quimica) equilibrio liquido-liquido

ACESSO AO ARTIGO

Documentos Relacionados