Solvent extraction of metals with potassium-dihydro-bispyrazolyl-borate

The extraction of Cu(II), Ni(II), Co(II), Cd(II), Zn(II), Pb(II) and Mn(II) with potassium-dihydro-bispyrazolyl-borate (H2BPz2−) in dichloromethane has been studied. Extraction constants (log Kex) have been calculated for all metal systems and were compared with those obtained with dibenzoylmethane (DBM), thenoyltrifluoroacetone (HTTA) and 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (HPMBP). The method has been used for the determination of Cu(II), Co(II), Cd(II), Zn(II), Pb(II) and Mn(II) in standard alloys and for preconcentration of metal ions in synthetic samples.