Extraction of some transition metals with N,N-dibutyl-N '-benzoylthiourea into molten paraffin at 65 degrees C

The solid-liquid extraction behaviour of some transition metals (Cu(II), Co (II), Ni(II), Cd(II) and Pb(II)) by the use of N,N-dibutyl-N'-benzoylthiour ea as an extractant in paraffin (58-60 degrees C) has been investigated at 65.0 +/- 0.5 degrees C. The effect of equilibration time, pH of the aqueous phase, concentration of extractant and solid solvent used on the extractio n efficiency of these metals have been discussed. The interferences of vari ous ions are examined. The method has been applied to the determination of these metals in synthetic samples, mushrooms and sediment. (C) 2000 Elsevie r Science B.V. All rights reserved.