微分阳极溶出伏安法测定脱脂奶粉中痕量砷

DIFFERENTIAL ANODIC STRIPPING VOLTAMETRIC DETERMINATION OF TRACE OF ARSENIC IN DEFATTED MILK POWDER

本文提出以 KBH_4为还原剂,使砷、锑、铋定量生成氢化物与基体溶液分离,以乙醇∶水(1.5∶1)混合液和金(Ⅲ)溶液作为 H_3Sb、H_3Bi 和 H_3As 的吸收液,未见 H_3As 损失。将 H_3As 的吸收液用同位镀金膜电极在0.8～1.0mol/L HCl 底液中微分阳极溶出伏安法测定脱脂奶粉中痕量砷,可获得满意结果。

The As(Ⅲ)Sb(Ⅲ)Bi(Ⅲ) are first reduced with KBH,to H_3Sb,H_3Asand H_3Bi,and then absorbed by ethyl-alcohol-water-gold(Ⅲ)solution.No lossof H_3As was found.The As absorbing solutions were determined byanodic stripping voltametry using a thin film gold electrode.The method hasbeen applied to analysis of defatted milk powder with satisfactory results.