【摘要】 研究了显色剂 4 ( 2 噻唑偶氮 ) 5 二甲氨基苯胺 (简称TADMA)与铑 的显色反应。结果表明 ,在 pH3 2～ 4 8范围内 ,铑 与TADMA反应形成 1∶2红色络合物 ,加入无机酸后色泽加深 ,络合物的表观摩尔吸光系数为 1 2 1× 10 5,铑质量浓度在 0～ 0 92 μg/mL范围内服从比尔定律。本方法操作简便 ,灵敏度高 ,选择性好 ,常见金属离子在一定范围内无干扰 ,用于催化剂中微量铑的测定 ,结果满意更多还原

【Abstract】 The color reaction between rhodium*# and 4 (2 thiazolylazo) 5 dimethylamino aniline(TADMA) has been studied The experimental results show that Rh*# reacts with TADMA at pH3 2-4 8 to form a red complex which can be changed into another deeply colored stable species by addition of mineral acid Its apparent molar absorptivity is 1 21×10 5L·mol -1 ·cm -1 at 619nm Beer’s law is obeyed in the concentration range of 0-0 92μg/mL for Rh*# at 619nm The molar ratio of Rh*# to TADMA is 1∶2 in the complex The method has more sensitivity and selectivity Most common ions don’t interfere,it has been applied to the determination of rhodium in catalysts with satisfactory results更多还原