钨Ⅵ-5′-硝基水杨基荧光酮-CTMAB体系显色反应及其分析应用

Color reaction of tungsten with 5′-nitro-salicylfluorone and CTMABand its analytical application

研究了钨与 5′ 硝基水杨基荧光酮 -溴化十六烷基三甲基铵体系的显色反应。结果表明 ,在 0 2 4～ 0 78mol/L盐酸介质中 ,W 与 5′ 硝基水杨基荧光酮生成桔红色络合物 ,其最大吸收波长为 5 2 2nm ,Δλ =5 4nm ,表观摩尔吸光系数为 1 5 8× 10 5,测定的线性范围为 0～ 13 μg/2 5mL ,本方法用于合金钢中钨的测定 。

In the presence of cetyltrimethyl ammonium bromide(CTMAB), an orange red colored complex of tungsten*& with 5′ nitro salicylfluorone(5′ NSF) forms in the medium of 0 24 0 78 mol/L HCl Its maximum abosrption is at 522nm,and the apparent molar absorptivity is 1 58×10 5L·mol -1 ·cm -1 Beer's law is obeyed for 0-13μg/25mL of tungsten. The proposed method has been applied to the determination of tungsten in alloy steels with satisfactory results