偶氮氯膦Ⅲ光度法测定硅铝钡合金中钡  

Spectrophotometic determination of barium in Si-Al-Ba alloy with chlorophosphonazo Ⅲ

作　　者：钟国秀[1] 杨浩义[1] 黄清华 

机构地区：[1]湖北省机电研究设计院,湖北武汉430070 [2]湖北省建材研究设计院,湖北武汉430071

出　　处：《冶金分析》2007年第11期62-64,共3页Metallurgical Analysis

摘　　要：研究了偶氮氯膦Ⅲ与钡的显色反应及共存离子的影响。结果表明，在pH10．0的氨水-氯化铵缓冲溶液中，钡与显色剂形成稳定的绿色络合物，最大吸收波长为670nm，表观摩尔吸光系数为6．49×10^4。在25ml的溶液中，钡量在0～50μg范围内符合比尔定律，显色反应具有很高灵敏度。加入三乙醇胺和邻菲罗啉掩蔽样品中大量的铝、铁，加入氟硼酸钾掩蔽钙，可直接测定硅铝钡合金中钡含量。测定结果与认定值相符，其相对标准偏差（RSD）小于2％。The color reaction of reagent chlorophosphonazo Ⅲ with barium was studied. In a medium of NH3. H2O-NH4Cl at pH10, barium reacts with the reagent to form a green complex which exhibits an absorption maximum at 670 nm with a apparent molar absorptivity of 6.49×10^4 L mol^- 1 cm ^-1. Beer＇ s law is obeyed in the range of 0-50 μg/25 mL for barium. The effect of aluminium and iron on the determination of barium can be overcome by complexing them with triethanolamine and 1,10- phenanthroline. Interference from calcium can be eliminated by using potassium fluoroborate. The proposed method has been applied to the determination of barium in Si-Al-Ba alloy with the RSD（n=5）of less than 2%. The determination results are agreement with the certified values.

关 键 词：偶氮氯膦Ⅲ 钡 分光光度法 硅铝钡合金 

分 类 号：TG115.3[金属学及工艺—物理冶金]