铁-荧光镓极谱络合吸附波的研究

Studies on Polarographic Adsorptive Complex Wave of Iron (III)-Lumogallion

在 p H6.1 0的 0 .1 mol/L ( CH2 ) 6 N4-HCl底液中 ,用单扫示波极谱法可获得铁( ) -荧光镓体系灵敏的络合吸附波。在 1 .0× 1 0 - 7～ 7.0× 1 0 - 6 mol/L范围内 ,铁浓度与波高呈线性关系 ,检测限达 7.0× 1 0 - 8mol/L,已成功地应用于金属镁粉中的铁和铝的测定 ,并测得电活性络合物的组成为铁∶荧光镓 =1∶ 1 ,条件形成常数β=3 .2× 1 0 4,表面电极反应速率常数 ks为 2 .9s- 1 。

In pH 6.10 (CH 2) 6N 4 HCl buffer, a sensitive adsorptive complex wave of Fe(Ⅲ) lumogallion(LMG) was obtained by single sweep polarography. The change of peak height with the concentration of iron was linear in the range from 1.0×10 -7 mol/L to 7.0×10 -6 mol/L. The detection limit was 7.0×10 -8 mol/L. It was used to determine the content of iron and aluminium in metal magnesium powder. The composition of the complex was detected as Fe(Ⅲ)∶LMG =1∶1. The conditional stability constant was determined as β =3.2×10 4. The rate constant of the surface electrochemical reaction was determined as k s=2.9 s -1 .