碲(Ⅳ)-硫氰酸盐-乙基紫高灵敏显色反应的研究及应用

Spectrophotometric Determination of Trace Tellurium(Ⅳ) With Thiocyanate and Ethyl Violet in the Presence of Polyvinyl Alcohol

在PVA存在下,于0.36～0.84mol/L硫酸中,Te(Ⅳ)-SCN^--EV-体系的λ_(max)=560nm,ε=1.55×10~6,含碲量在0～5μg/25ml范围,符合比耳定律。方法已用于测定纯金属、矿石及烟尘中的碲,结果满意。

The titled method is proposed. A soluble blue-violet complex is formed in a medium of strong acidity and shows maximal absorbance at 560nm with molar absorptivity 1. 55×10~6 L. mol^(-1). cm^(-1). Beer＇s law is followed over the range of 0 to 5.0μg/25ml. Most ions do not interfere with the determination and the method has been applied to determine tellurium in actual samples with satisfactory results.