Determination of Nickel in Sea Water and Common Salt by Atomic Absorption Spectrophotometric Method with 2-Hydroxy- 1-naphthaldoxime Extraction

Abstract

A micro amount of nickel contained in sea water and common salt was determined by atomic absorption spectrophotometry in conjunction with extraction technique. Nickel was reacted with 2-hydroxy-1-naphthaldoxime (HNA) to form a 1:2 (Ni: HNA) stable complex, which was extracted into chloroform.The optimum conditions on the extraction of nickel were examined.The effect of coexisting diverse substances in the aqueous phase were also examined. The extracted complex was decomposed with nitric acid-perchloric acid mixture, and then dissolved with 0.1N hydrochloric acid.The resulting solution was sprayed into an acetylene-air flame.Less than 10 μg of nickel was quantitatively extracted into 10ml of 0.02 M HNA chloroform solution from aqueous solution at pH 5.8, by shaking for 10 min.When a known amount of nickel was added to the sea water samples, the nickel was recovered satisfactory. The proposed method has been successfully applied to the determination of micro amount of nickel in sea water and common salt.