PART 3. THE EXTRACTION OF Co2+, Ni2+, Cu2+AND Zn2+USING NOVEL DITERTIARY-AMINEEXTRACTANTS

Abstract
The syntheses of N-N-octyl-2-2'-pyridylimidazole and N,N'-di-n-octyl-(a)-aminopicoline are presented. Their extraction properties are compared with that of an aliphatic diamine N,N,N',N'-tetraoctylethylene-diamine. The reagents, dissolved in chloroform, were used to extract divalent cobalt, nickel, copper and zinc from aqueous chloride medium. Two extraction mechanisms are postulated for the extraction of these metals, and extraction data are discussed in terms of these postulates. Extraction of the copper(II) ion at low pH values with amines is best effected by the inclusion of aromatic nitrogen atoms into a diamine extractant.