二安替比林苯乙烯甲烷光度法测定加碘盐中的碘(Ⅴ)

Photometric Determination of Iodine(Ⅴ) in Table Salt with Diantipylphenylvinylmethane

在磷酸介质中 ,Mn( )和吐温 - 40存在下 ,二安替比林苯乙烯甲烷 (DAPVM)与 I( )生成红色产物 ,λmax=5 40 nm,ε=2 .11× 10 5L·mol-1·cm-1,碘含量在 0— 16 8μg·L-1范围内符合比耳定律。体系灵敏度高 ,稳定性好。用于加碘盐中碘的测定 ,结果令人满意。

In the phosphoric acid medium including Mn(Ⅱ)and tween-40,diantipyrylphenylvinylmethane(DAPVM) reacts with I(Ⅴ) to form a red product with an absorption maximum at 540nm and apparent molar absorptivity of 2.11×10 5L·mol -1 ·cm -1 .Beer's law is obeyed in the range of 0-168μg of iodine(Ⅴ) per liter.The method was applied to the determination of the trace iodine in the table salt with satisfactory results.