【摘要】 研究了新试剂 5 (o 硝基 )亚甲基若丹宁 (o NBR)与贵金属离子Au(III)的显色反应 ,在pH =4的HAc NaAc缓冲溶液中 ,乳化剂 OP存在下 ,Au(III)与o NBR生成 1∶2的稳定络合物 ,λmax=4 2 0nm ,ε =5 .0 3× 10 4L·mol-1·cm-1,金的含量在 0～ 5 0 μg/ 2 5mL范围内符合比尔定律 .方法用于金矿石中痕量金的测定 ,结果满意更多还原

【Abstract】 The color reaction of 5-(o-nitrobenzylidene) rhodanine(o-NBR) with gold(III) has been studied. In the presence of emulsion-OP , o-NBR can react with Au(III) to form a 2∶1 stable complex. The molar absorptivity is 5.03× 10 4 L·?mol -1·cm -1 at 420?nm. Beer’s law is obeyed in the range of 0～50?μg Au/ 25?mL. This method can be applied to the determination of gold in ore with satisfactory results.更多还原