茜素黄GG分光光度法测定纯铝和铝合金中铁

Spectrophotometric Determination of Fe(Ⅲ) in Aluminum and Aluminum Alloys with Alizarin Yellow GG as Color Reagent

在溴化十六烷基吡啶（CPB）存在下，用分光光度法研究了茜素黄GG与铁（Ⅲ）的显色反应性能。在pH8．0～10．0范围内，茜素黄GG与铁（Ⅲ）形成3：1的红色络合物。该络合物的最大吸收波长在470nm处。铁的质量浓度在1．0mg·L^-1以内服从比耳定律，表观摩尔吸光率为5．281×10^4L·mol^-1·cm^-1。所拟方法用于纯铝及铝合金样品中微量铁的测定，测定值与已知值相符，测定值的相对标准偏差（n=8）均小于3％。

Chromogenic reaction of alizarin yellow GG with ferric ion in an ammoniacal buffer of pH 8. 0- 10. 0 and in the presence of CPB was studied by spectrophotometry. A red complex with mole ratio of 3 to 1 between alizarin yellow C-G and Fe（ Ⅲ） was formed, having its absorption maximum at the wavelength of 470 nm, at where the apparent molar absorptivity was found to be 5. 281 × 10^4L · mol^-1· cm^-1. Beer＇s law was held in the range within 1. 0 mg · L^-1 of Fe（ Ⅲ ）. The proposed method was used in the determination of iron in aluminum and aluminum alloys, with the results found in consistency with the known values, and giving values of RSD＇s （n= 8） less than 3 %.