【摘要】 本文研究了meso-四-（4-甲氧苯基）卟啉与铅的高灵敏显色反应及双波长和导数光谱行为。当有Tween-80存在时,在强碱性介质中,于沸水浴上加热32min,显色反应能定量进行。该体系的表现摩尔吸光系数(ε_466.5)为1.77×10⁵,双波长的ε_466.5/422为3.16×10⁵,四阶导数光谱的有效摩尔响应值为2.67×10⁶。此显色体系用于合成样品中痕量Pb的测定,回收率在96.8～98.2％之间。更多还原

【Abstract】 It was found that meso-tetrakis-(4-methyoxyphenyl)-porphyrin gives a very sensitive reaction with lead (Ⅱ). A detailed study on this reaction was performed, including an investigation about the dual-wavelength spectrophoto-metry and the derivative spectrum of the complex. The complete formation of the complex is effected by heating a 0.08 mol/L NaOH solution in the presence of Tween-80 for 32 min. The apparent molar absorptivity is 1.77×105 at 466.5 nm, and the use of dual-wavelength spectrophotometry and fourth derivative can further improve the sensitivity to 1.78 and 15.4 times respectively. The method has been tested with simulated samples, the recovery of trace lead range from 96.8 to 98.2%.更多还原