磷酸三丁酯萃取-火焰原子吸收光谱法测定高纯黄磷中痕量铁和锌

Determination of trace iron and zinc in high purity yellow phosphorus by flame atomic absorption spectrometry with tributyl phosphate extraction

用火焰原子吸收光谱（FAAS）法直接测定高纯黄磷消解液中痕量Fe和Zn,结果发现抑制作用很强。磷酸三丁酯（TBP）作为萃取剂可将高纯黄磷消解液中的磷酸萃取分离,从而降低磷酸与Fe、Zn的络合作用同时降低磷酸的黏度,减少了用FAAS测定高纯黄磷中痕量Fe与Zn的抑制作用。试验优化后的萃取条件为：样品和TBP的体积比为1∶1,振荡1 min,静置30 min。此方法测定高纯黄磷中Fe和Zn的检出限分别为0.02 mg/L和0.01 mg/L,加标回收率均在90%～110%之间。

If trace iron and zinc in high-purity yellow phosphorus digestion solution was directly determined by flame atomic absorption spectrometry（FAAS）,the inhibiting effect was strong.In this study,the phosphoric acid in high-purity yellow phosphorus digestion solution was extracted and separated using tributyl phosphate（TBP） as extracting agent,reducing the complexing action between phosphoric acid with iron and zinc.Subsequently,the viscosity of phosphoric acid was reduced,decreasing the inhibiting effect in FAAS determination of trace iron and zinc in high-purity yellow phosphorus.The optimized extraction conditions were： volume ratio of sample and TBP of 1∶1,oscillating for 1 min,and placing for 30 min.The detection limits for Fe and Zn in high-purity yellow phosphorus by this method were 0.02 mg/L and 0.01 mg/L,respectively.The recovery of standard addition were in the range of 90 %-110 %.