Determination of Nickel with 1-(2-thiazolylazo)-2-naphthol bySolid-liquid Separation after Liquid-liquid Extraction and Spectrophotometry

A spectrophotometric method for the determination of nickel based upon the extraction with TAN into a molten naphthalene is described. The nickel-TAN chelate is extracted quantitatively in the pH range 5.0 - 8.O. Zinc, iron(Ⅱ) and iron(Ⅲ) are masked with pyrophosphate. Copper and cobalt are masked with DTCS. Beer's law is obeyed over the nickel concentration range 2.0 - l8.Oμg per 20 ml of dioxane. The molar absorptivity at 595 nm is 4.1 x 104 1.mo1e-1.cm-l . Sandell sensitivity is 0.0014 ~g of nickel per ㎠