泡塑富集、MIBK萃取/硫脲浸取FAAS法测定地质样品中低含量金

Pre-concentration and Determination of Poor Gold in Geological Ore Samples by Flame Atomic Absorption Spectrometry after Being Extracted by Thiourea or by MIBK

地质样品中金的含量低于0.3 g/t时,用常规的泡塑吸附硫脲解脱FAAS法测定,因为受到硫脲体积的限制和仪器检出限的制约,常常产生较大误差。简单减小硫脲体积,会导致解脱不完全而使结果偏低。本文试用将吸附好的泡塑灰化,再经溶解、M IBK萃取或直接用热硫脲浸取定容于较小的体积,然后使用火焰原子吸收分光光度计进行测定,取得较理想的结果,而且比使用石墨炉原子吸收经济适用。

Gold that is lower than 0.3 g/t in poor ore samples often can＇t be determined correctly because of the limit of the instrument when we use the usual pre-concentration determination by AAS. In this paper, plastic foam that has adsorbed gold is ashed, dissolves in aqua regia and gold is extracted by MIBK, or directly separated with hot 10g/L Thiourea -HCI（ 1 ＋ 99） solution, and gets into a smaller volume solution, then determined by flame atomic absorption spectrometry.