3.5-Br_2-PADAP-IO_4^--SCN^-三元离子缔合物测定微量IO4^-的研究

Study on the Determination of Trace Amount of IO_4^- with 2-(3.5-Dibromo-2-Pyridylazo)-5-Diethylaminophenol

:3.5- Br2 - PADAP在酸性介质中质子化 ,与 IO4 -和 SCN-形成三元离子缔合物 ,其表观摩尔吸光系数为 1.51× 10 5L· mol-1· cm-1,缔合物的组成比为 3.5- Br2 - PADAP:IO4 -:SCN-=1:1:1.提供了测定微量 IO4 -的新的分光度法 .可用于加碘食盐、海带样品中含碘量的测定 .

The optimum conditions of ion association of protonated 2 (3.5 dibromo 2 pyridylazo) 5 diethylaminophenol (3.5 Br 2 PADAP) with IO 4 and SCN formed in H 2SO 4 medium was investigated in this paper. The molar absorptivity is 1.51×10 5 L·mol -1 ·cm -1 and the composition ratio of 3.5 Br 2 PADAP: IO 4 :SCN is 1∶1∶1.A new method for the determination of trace amount of IO 4 was developed and applied to determine trace amount of iodine in table salt with satisfactory results.