均三溴偶氮胂双波长分光光度法测定锶

Dual-Wavelength Spectrophotometric Determination of Microamount Strontium with Tribromo-Arsenazo

本文研究了新显色剂均三溴偶氮胂(TBA)与锶的显色反应。实验表明:锶与TBA在氨-氯化铵缓冲溶液中形成稳定的1∶2络合物。采用双波长分光光度法,以490nm为参比波长、600nm为测定波长,测得络合物的摩尔吸光系数为4.6×10~4,锶量为0-9μg/25mL符合比尔定律。用于电子工业钛酸锶烧结物中游离氧化锶的测定,结果令人满意。

The conditions of chromogenic reaction of strontium(Ⅲ) with Tribromo-Arsenazo (TBA)have been studied. In pH 11 buffer medium of NH-NH Cl, strontium(Ⅱ) and TBA form 1:2 complex. The complex can be determined by dual-wavelength spectrophotometry with tribromoarsenazo at 600-490 nm. The molar absorptivity of the strontium complex is 4.6×10~4, which 1.24 times higher than single-wavelength. The Beer's law is obeyed. It has been applied to determine the strontia in sintering strontoum titanate with satisfactory results.