摘要
在硫酸介质中,2-(5-溴-2-吡啶偶氮)-5-二乙氨基酚(5-Br-PADAP)与IO_3^-及SCN^-生成红色缔合物,用于吸光光度法分析微量IO_3^-,加入表面活性剂吐温-80可以提高测定的灵敏度和选择性。在最大吸收波长550nm处,可测IO_3^-浓度范围为0～2.45μg·ml^(-1),摩尔吸光系数ε为8.2×10~4,离子缔合物的组成比为5-Br-PADAP:IO_3^-:SCN^-=2:1:4。经测定硝酸钠和氯酸钾中IO_3^-的回收率为97.3％～101.5％,结果令人满意。
2- ( 5-Bromo-2-Pyridylazo) -5-Diethylaminophenol reacts with IO3- and SCN- to form a red coloured ion-associated complex in acid medium. Based on this reaction, a spectrophotometric method for determination of IO3- in sulfate acid medium is proposed. Surfactants are used to improve the sensitivity and selectivity. The molar absorption at 550nm is 8. 2×104, the range obeying Beer' s Law is 0-2.45μg ?ml-1 and the composition ratio of 5-Br-PADAP : IO3- : SCN- is 2 : 1 : 4. The new method has been used for determination of IO3- in chemical reagents, such as KClO3 and NaNO3, and the recovery ratio is 97. 3%-102. 9%.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
1996年第4期218-219,共2页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
