摘要
本文报道了树脂相分光光度法测定地质样品中微量镁的研究。结果表明，利用国产７３２＃阳离子交换树脂作为载体，在碱性介质中，镁离子能够与镁试剂Ⅱ形成稳定的兰色配合物，使树脂载体里兰色，配合物的最大吸收波长为６５０ｎｍ，方法集分离、富集和测定于一体，其摩尔消光系数ε＝１．１２×１０５，ＲＳＤ＝５．３％，镁含量在０～３４μｇ／２５０ｍｌ范围内与吸收值Ａ成良好的线性关系，方法已应用于地质样品中微量镁的测定，取得满意的结果。
A rapid resin Phase spectrophotometry method was developed for determination of micro amounts of magnesium in geological samples. 732 type cation exchange resin was utilized as solid phase supporter, absorptive magnesium on canon exchange resin was formed complex compound with magneson Ⅱ in the alkalinous medium.The wavelength of absorption maximum is 650 nm. The method gathers separation、enrichment and determination together. It bas high sensitivity (ε=1. 12 ×105) and good accuracy (5μg Mg was measured for 10 time RSD=5. 3%). Its linear range is 0～34μg/250ml. This method has been applied to the determination of magnesium in geological samples with satisfactory result.
关键词
地质样品
镁
比色法
树脂相光度法
Resin phase Spectrophotometry Method
Magnesium
Magneson Ⅱ
