Tween-80-5-Br-PADAP光度法同时测定微量铁和钴

Simultaneous Spectrophotometric Determination of Trace Ferrum and Cobalt with 5-Br-PADAP and Tween-80

研究了 5 Br PADAP与铁和钴同时显色反应及测定的适宜条件。试验证明 ,在 pH为 3 4的HAc NaAc介质中 ,显色剂与铁和钴形成稳定有色络合物 ,λmax均为 5 85nm ,铁量 0～ 10 μg·2 5mL-1,钴量 0～ 12μg·2 5mL-1符合比耳定律 ,表观摩尔吸光系数εFe585为 7 18× 10 4 ,εCo585为 9 2 7× 10 4 。据此测定水样中微量铁和钴 ,结果良好。

A new simultaneous method for the determin at ion of ferrum and cobalt with 5-Br-PADAP by spectrophotometry in the presence of Twen-80 is studied.The results showed that in pH=3 4 HAc-NaAc buffer mediu m,ferrum and cobalt can formed colored complexes with 5-Br-PADAP.Its maximum a bsorption wavelengthes are at 585 nm.Beer′s law is obeyed for the concentratio n of ferrum in the range of 0—10 μg·25 mL- -1 and 0—12 μg·25 mL- -1 of cobalt.The apparent molar absorptivities are ε- Fe 585=7 18×10-4 and ε- Co 585=9 27×10-4 resp ectively.This method has been applied to the determination of ferrum and cob alt in water sample with satisfactory results.