对磺酸基苯基亚甲基若丹宁光度法测定三乙酸甘油酯中的汞

Study on Spectrophotometric Determination of Mercury in Triacetin with p-Sulfobenzylidene-Rhodanine

合成了一种新的若丹宁类试剂对磺酸基苯基亚甲基若丹宁 (SBDR) ,并用红外光谱和元素分析进行结构鉴定。研究了该试剂与汞的显色反应 ,在 p H4.0的HAc- Na Ac缓冲介质中 ,吐温 - 80存在下 ,SBDR与汞反应生成 2∶ 1稳定络合物 ,λmax=5 1 0 nm,ε=1 .0 7× 1 0 5L· mol- 1· cm- 1。汞含量在 0～ 3 0μg/2 5 m L内符合比耳定律。方法用于三乙酸甘油酯中汞含量的测定 ,结果满意。

The color reaction of mercury with p-sulfobenzylidene-rhodanine (SBDR) was studied. In the presence of pH 4.0 HAc-NaAc solution and Tween-80 medium, SBDR could react with mercury (II) to form a stable 2∶1 complex. The molar absorptivity was 1.07×10 5 L·mol -1·cm -1 at 510 nm. Beer's law was obeyed in the range of 0～30 μg/25 mL. This method has been applied to the determination of mercury in triacetin with satisfactory results.