对乙酰基偶氮氯膦光度法测定硅钡镁合金中钡  

Spectrophotometric determination of barium in Si-Ba-Mg alloy with p-acetylchlorophosphonazo

作　　者：罗道成[1] 刘俊峰[1] 

机构地区：[1]湖南科技大学化学化工学院,湖南湘潭411201

出　　处：《冶金分析》2008年第1期74-76,共3页Metallurgical Analysis

摘　　要：研究了对乙酰基偶氮氯膦（CPApA）与钡的显色反应。结果表明，在0．40mol／LH3PO4介质中，CPApA与钡（Ⅱ）反应生成2：1稳定络合物，其最大吸收波长为646nm，表观摩尔吸光系数为1．35×10^5L·mol^-1·cm^-1。钡质量浓度在0～0．80mg／L范围内符合比尔定律。方法已用于硅钡镁合金中钡的测定，结果与重量法相符，实际样品分析结果的相对标准偏差小于3％，加标回收率为97．4％～102．6％。The color reaction of barium with p-acetylchlorophosphonazo （CPApA） was studied. In 0. 40 mol/L H3PO4 medium, p-acetylchlorophosphonazo reacts with barium （Ⅱ） to form a stable 2 ： 1 complex, whose maximum absorption wavelength is at 646 nm and apparent molar absorptivity is 1.35×10^5L·mol^-1·cm^-1. Beer＇s law was obeyed in the range of 0-0.80 mg/L for barium. The barium content in Si-Ba-Mg alloy has been determined by this method, and the results are in good agreement with those provided by gravimetry. The relative standard deviation is less than 3% and the recoveries of samples are between 97.4% and 102.6%.

关 键 词：分光光度法 硅钡镁合金 对乙酰基偶氮氯膦 钡 

分 类 号：TG115.3[金属学及工艺—物理冶金]