Determination of Copper in Sea Water, Brine and Common Salt by Atomic Absorption Spectrophotometric Method with 5-Bromo-Salicylaldoxime Extraction

Abstract

A micro amount of copper contained in sea water, brine and common salt was determined by atomic absorption spectrophotometry in conjunction with extraction technique. Copper formed a complex with 5-bromo-salicylaldoxime (5-Br-SA), and was extracted into chloroform. The extract was decomposed with nitric acid-perchloric acid mixture, and then dissolved with 0.1 N hydrochloric acid. This resulting solution was sprayed into an acetylene-air flame. To find the optimum condition for the extraction of copper, the effect of pH, concentration of 5-Br-SA, shaking time, and diverse ions in the aqueous phase were examined. Less than 10μg of copper was quantitatively extracted into 10ml of 0.02M 5-Br-SA chloroform solution from aqueous solution at pH4.0, by shaking for 10 min. When a known amount of copper was added to the sea water samples, the copper was recovered satisfactorily. Some samples of sea water, brine and common salt were analized.