两次双波长分光光度法测定铅和汞

Simultaneous Determination of Mercury and Lead by Twice Dual-Wavelength Spectrophotometric Method

基于卟啉试剂ＴＡＰＰ与Ｐｂ￣（２＋）、Ｈｇ￣（２＋）在碱性介质中有灵敏的显色反应，建立了两次双波长分光光度法同时测定Ｐｂ、Ｈｇ的新方法，摩尔吸光系数分别为４．５９×１０￣５和４．３２×１０￣５ｍｏｌ￣（－１）·ｃｍ￣（－１）·Ｌ；可同时测定１：５～１０：１范围内的Ｐｂ和Ｈｇ，用于水中Ｐｂ和Ｈｇ的同时测定，结果满意。

A sensitive twice dual-wavelength spectrophoto-metric method has been developedfor the simultaneous determination of trace Hg and Pb,based on the formation of colourcomplexes of the two metals with meso-tetra-(p-trimethylammonium phenyl)porphyrin in0.02mol/L NaOH medium. The molar absorptivities are 4.59 × 10￣5 and 4. 32 × 105 L·mol-1·cm-1 for Pb and Hg respectively. The method gave satisfactory restilts in simultaneous de-termination of Pb and Hg in the tap water.