流动注射催化动力学荧光法测定痕量钌

Flow Injection Catalytic Kinetic Spectrofluorimetric Determination of Trace Amounts of Ruthenium

利用2-吡啶甲醛和苯甲酰肼合成了一种新的荧光试剂2-吡啶甲醛苯甲酰腙,对其进行了红外光谱和元素分析,证明了目标化合物的生成。运用2-吡啶甲醛苯甲酰腙-KBrO3这一反应体系为指示反应,采用正相流动注射2-吡啶甲醛苯甲酰腙乙醇水溶液试剂作为载流,注入样品（钌溶液）进行实验,发现2-吡啶甲醛苯甲酰腙被KBrO3氧化后荧光增强,Ru^3＋是极好的催化剂。据此,研究了该指示反应的适宜条件,共存离子的影响,并探讨了反应机理,建立了快速、简便、高灵敏度、高选择性流动注射催化动力学荧光测定钌的方法,检出限0.60μg/L,线性范围2.0-400μg/L。本方法成功地应用于人工合成样及矿样中痕量钌的测定。

A flow injection （FI） kinetic spectrofluorimetric method for the determination of trace amounts of ruthenium was developed and the possible mechanism of catalytic reaction was discussed. 2-Pyridine carboxaldehyde benzoylhydrazone（PCBH） was newly synthesized and it＇s IR and elemental analysis were established. The method was based on the fluorescence enhancing reaction of PCBH with potassium bromate,which was catalysed by Ru^3＋ in aqueous medium at pH 6.70 and 55 ℃. Under these experimental conditions,the oxidized product of PCBH had excitation and emission maxima at 284 and 377 nm, respectively. The linear range of this method was 2.0 - 400 μg/L with a RSD of 1.8% from a series of t 1 standards each containing 50 μg/L of ruthenium. The detection limit was 0.60 μg/L of ruthenium. A high analysis rate of 18 samples per hour was obtained by the method. The proposed method was successfully applied to determine ruthenium in synthetic mixtures and mineral samples, and the results were greeable with the standard values.