FAAS Determination of Copper in Chromium Plating Solution

FAAS was applied to the determination of copper in chromium plating solution. The chromium plating solution was acidified with conc. H2SO4,and then Cr(Ⅵ) was reduced into Cr(Ⅲ) by the addition of H2O2. Copper(Ⅱ) was precipitated completely by displacement with Zn from the sample solution,and dissolved in HNO3(1+1) and made up to 1 L with water,which was used for FAAS determination. The working condition of instrument was described in detail. Linear relationship between values of absorbance and mass concentration of Cu found was in the range within 4.0 mg·L-1,with values of RSD′s (n=6) 0.28%. Detection limit (3S/N) of the method obtained were 0.006 1 mg·L-1 respectively. The proposed method was applied to the analysis of 4 samples of chromium plating solutions,and value of recovery found by the standard addition method was in range of 95.0% to 106.0%.