【摘要】 本文研究了以铬黑T作TPPS₄和Fe（Ⅲ）的混合配位体,并在弱酸性条件下运用了铬黑T,首次突破了Fe（Ⅲ）)与TPPS₄的成络反应条件:在pH4.0的HAc-NaAc缓冲溶液中,沸水浴加热15min,以1:1:1的组成形成TPPS₄-铬黑T-Fe（Ⅲ）混配络合物,λ_max=392um,ε＇=2.07×10⁵L·mol^-1·cm^-1,稳定常数为8.7×10⁷,Fe（Ⅲ）含量在0～4.5μg/25ml范围内成线性关系.将此方法用于纯铜、茶叶、烟草样品中的痕量铁的测定,获得了较满意的结果.更多还原

【Abstract】 The color reaction of Fe(III) with meso-tetra(4-sulphophenyl) porphyrin(TPPS4) was studied in the presence of eriochrome black T(EBT). Fe(III) can react with TPPS, and EBT to form a ternary complex at pH 3. 6 - 4.3 ,after heating in boiling water bath for 15 min. The absorbance maxium is measured at 392 nm with the apparent molar absorptivity of 2. 07X105 L ?mol-4 ?cm-1. The molar ratio of the ternary complex is 1:1:1. Beer’s law is obeyed for Fe(III) in the range of 0~4.5g/25 ml. This method has been applied to the determination of iron in the pure copper, tea-seaves and tobacco with satisfactory results.更多还原