铁-抗坏血酸-3,3′,5,5′-四溴联苯-双-(重氮氨基偶氮苯)催化褪色光度法测定痕量铁

Catalytic Kinetic Spectrophotometric Determination of Trace Iron Using Iron-Ascorbic acid-3,3′,5, 5′-Tetrabromodiphenyl-bis-diazoaminoazobenzene System

研究了在硫酸介质中 ,铁 催化抗坏血酸还原 3 ,3′,5 ,5′ 四溴联苯 双 (重氮氨基偶氮苯 )(TBDPBDAA)而褪色的反应及其动力学条件 ,测定了反应级数和表观活化能 ,建立了催化动力学光度法测定痕量铁的新方法。方法的测定范围为 0～ 0 .0 80mg L;测定下限为 4.3× 1 0 - 1 0 g mL。用于测定发样、茶叶、面粉中的痕量铁 ,与电感耦合等离子体原子发射光谱法 (ICP AES)对照 ,结果满意。

Decolourization of 3,3',5,5'-tetrabromodiphenyl-bis-diazoaminoazobenzene by reduction of ascorbic acid in sulfuric acid medium using iron (II) as catalyst was investigated. A method of the catalytic, kinetic spectrophotometry for the determination of iron(II) was established. The linear range of the method is 0 similar to 0.08 mug/L and determination limit of 4.3 x 10(-10) g/mL. This method has been applied to the determination of trace iron(E in hair, tea and flour with satisfactory results.