新试剂PAPL与钯显色反应的分光光度法研究

Spectrophotometric study on colour reaction of new reagent, (2-pyridylazo)phloroglucin,with palladium in the presence of CTMAB

研究了在表面活性剂溴化十六烷基三甲基铵（CTMAB）存在下,新显色剂（2-吡啶偶氮）间苯三酚（PAPL）与钯的显色反应和测定条件,提出了测定徽量钯的新方法。在pH3.8下,配合物的最大吸收蜂波长为510nm,表观摩尔吸光系数ε510=3.0×104L·mol-1·cm-1,钯量在0～60μg/25ml内遵守比耳定律。方法简便,适用于催化剂中钯的测定。

The colour reaction of a new reagent,(2- pyridylazo) phloroglucin,with palladium in the presence of CTMAB was studied,A stable reddish orange complex is found in the medium of pH 3.8.The maximum absorption of the complex occurs at 510nm.The apparent molar absorptivity at 510 nm is 3.0×10~4L·mol^(-1)·cm^(-1).Beer's Law is obeyed for palladium (Ⅱ) in the range of 0～60μg/25ml. The molar ratio of palladium (Ⅱ) to the reagent in the complex is 1:3.The method has been success-fully applied to the determination of palladium content in catalysts.