二溴羟基苯基荧光酮荧光熄灭法测定微量钨

A Fluorescence Quenching Method for the Determination of Trace Amounts of Tungsten with 2,3,7-Trihydroxy-9-Dibromo-Hydroxyphenyl Fluorone(DBH-PF)and Cetyltrimethylammonium Bromide

本文用荧光熄灭法研究了二溴羟基苯基荧光酮(DBH-PF)-溴化十六烷基三甲胺(CT-MAB-W(Ⅵ)体系的显色反应和测定条件。在0.02～0.10mol/L硫酸介质中,钨与显色剂形成1:3的桔红色配合物,检出限为0.08ug/25mL,在0.08～1.00ug/25mL范围内具有线性关系。本法灵敏度高,选择性好,不经分离可直接测定合金钢中钨,结果满意。

W(Ⅵ)in steel alloys was rapidly determined by fl- uorometric quenching mehod with 2,3,7-trihydroxy-9- dibrom o-hydroxyphenyl fluorone(DBH-PF)and cetyltrimethylammonium bromide(CTMAB)as reagents. In H_2SO_4medium,W(Ⅵ),DBH-PF and CTMAB react to form a complex,lts composition was established by meth- ods of continuous variation and equilibration shift as W (Ⅵ):DBH-PF=1:3.Its maximum excitation wavelengt- hs are 470nm and 502nm,the maximum emission wavelength is 520nm.The linear range are is 0.08～ 1.00μg/25mL,the detection limit of W(Ⅵ)is 0.08μg/ 25mL.The method is free from interferences when NH_2OH·HCl and EDTA were used.It has been appllied to determine W(Ⅵ)in alloys with satisfactory results.