Extraction of nickel in the presence of ammonia with β-diketones containing phenyl and alkyl groups

The extraction of nickel chelates with β-diketones containing either alkyl or phenyl groups was examined in the absence and in the presence of ammonia in the aqueous solution, in order to define the effect of substituents and the coordinating effect of ammonia on the extraction. In the extraction of nickel chelates in the presence of ammonia, the extracted species were identified to be NiA₂(NH₃)₂] (A: β-diketone anion) and ammonia acts both as adduct-forming in the organic phase and as a masking reagent in the aqueous phase.