Abstract：The method for determination of palladium with 2-(5-bromo-4-methyl-2-pyridylazo)-5-dimethylaminoaniline (5-Br-4-CH3-PADMA) by dual-wavelength overlapping spectrophotometry has been developed. The experimental results show that in the medium of 1.08-3.06 mol/L H2SO4, palladium reacts with 5-Br-4-CH3-PADMA forming a stable 1∶1 blue-purple complex with two absorption peaks at 606 nm and 564 nm respectively, and the sum of absorbance at these two peaks shows good linearity with palladium concentration. Beer’s law was obeyed in the range of 0-1.04 μg/mL for palladium. The apparent molar absorptivity was 1.40 ×105 L·mol-1·cm-1. Most common ions do not interfere the determination of palladium. The proposed method has been applied for the determination of palladium in molecular sieve and palladium-carbon catalyst, the results were consistent with the reference values. The relative standard deviation(RSD, n=6) was 1.8% and 2.8%.
霍燕燕,韩权,杨晓慧,周梅. 双波长叠加2-(5-溴-4-甲基-2-吡啶偶氮)-5-二甲氨苯胺分光光度法测定钯[J]. 冶金分析, 2014, 34(10): 70-72.
HUO Yan-yan, HAN Quan, YANG Xiao-hui, ZHOU Mei. Determination of palladium by dual-wavelength overlapping spectrophotometry with 2-(5-bromo-4-methyl-2-pyridylazo)-5-dimethylaminoaniline. , 2014, 34(10): 70-72.
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