催化动力学光度法测定痕量铝

A Novel Catalytic Procedure for the Datermination of Ultratrace Aluminum

依据Al^(3+)对H_2O_2氧化■花青褪色的催化行为，建立了测定痕量铝的催化动力学分析法。本法线性测定范围为0~200μg/L，检测限为1．2μg/L.除Cu^(2+)、Fe^(3+)和Cr（Ⅵ）外，其余离子不影响测定。Fe^(3+)和Cu^(2+)的干扰可分别用铜铁试剂-氯仿和双硫腙-四氯化碳溶液萃取除去，而将Cr（Ⅵ）还原为Cr^(3+)即可有效地消除其干扰。测定了人发、茶叶和水样中的铝含量，结果满意。

A catalytic procedure for the determination of ultratrace aluminum was proposed based on Al^(3+) catalyzed H_2O_2-gallocyanine redox reaction in hexamine-hydrochloric acid buffer medium. The calibration graph is linear for 0 ~ 200 μg/L Al^(3+), and the detection limit is 1. 2 μg/L. The interfering effect of Fe^(3+) and Cu^(2+) could be effectively eliminated by extraction with cupferron-chlorform and dithizone-carbon tetrachloride, and that of Cr(Ⅵ ) by reducing to Cr(Ⅲ ). The procedure has been used to determine the aluminum content in human hair, tea and wastewater, and the results were satisfactory.