提出了火焰原子吸收光谱法测定镀铬液中的铜的含量.镀铬液经浓硫酸酸化后,滴加过氧化氢使铬(Ⅵ)完全还原为铬(Ⅲ).然后用金属锌将镀铬液中铜完全析出,用硝酸(1+1)溶解定容后,供火焰原子吸收光谱仪测定.对仪器的工作条件作了详细的叙述.吸光度与铜的质量浓度在4.0 mg·L-1以内呈线性关系,相对标准偏差(n=6)为0.28%.方法的检出限(3S/N)为0.006 1 mg·L-1.应用此法分析了4份镀铬液样品,以标准加入法做回收率试验,回收率在95.0%~106.0%之间.

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%.