α,β,γ,δ-四-(4-三甲铵基苯基)卟吩分光光度法测定岩石矿物中的微量铅

Spectrophotometric Determination of Traces of Lead in Rocks And Minerals with Meso-tetra-(4-trimethylammoniumphenyl)porphine

近年来,水溶性卟啉用作微量铅的显色试剂由于其高灵敏度而引起人们的注意并做了一些研究工作,但由于一般的水溶性卟啉对铅的选择性不太理想,而且发色时大多需要较长时间反应或加热,故具体应用的研究不多。有人,也曾采用阴离子交换树脂分离干扰离子。

This paper deals with the determination of trace amounts of lead in rocks and minerals.It is based on the reaction of Pb with meso-tetra-(4-trimethyla-mmoniumphenyl)porphine[T(4-TAP)P].Lead forms a colour complex with T(4TAP)Pat pH 9.5-12.5 in Na_(2)B_(4)O_(7)-NaOH buffer solution. The interfering ions were separated by passing through macro reticular basic anion exchange resin D235The colour system showing a λmax at 459nm (ε=2.5 × 10^(5)) obeys Beer’s law over the range 0-20μg in 25ml solution;this complex is stable for at least 2 hrs.