石墨炉原子吸收测定水体中铊基体改进剂用量及效果分析

Determination of thallium matrix modifier in water by graphite furnace atomic absorption spectrometry and its effect analysis

石墨炉原子吸收法是测定水环境中的铊较常用的方法,铊的灰化温度低,而氯离子的存在对铊产生负干扰,为消除基体干扰,实测中经常需加入基体改进剂,而分析标准中对于基体改进剂的用量并无明确规定。实验采用Pd+Mg(NO3)2为基体改进剂,通过测定铊元素时基体改进剂对氯离子的抑制效果,得出分析时基体改进剂的最佳用量,使样品分析中仪器处于最佳状态,检出限和校准曲线的相关性优于分析方法要求,从而保证分析结果良好的精密度和准确度。

Graphite furnace atomic absorption spectrometry is a commonly used method for the determination of thallium in water environment.The ashing temperature of thallium is low,and the existence of chloride ion has negative interference with thallium,In order to eliminate matrix interference,matrix modifier is often added in the actual measurement,but the amount of matrix modifier is not clearly specified in the analysis standard.Keywords:thallium;graphitefurnace;analysis;explore.Pd+Mg(NO3)2was used as matrix modifier in the experiment.By measuring the inhibition effect of matrix modifier on chloride ion when thallium was measured,the optimal dosage of matrix modifier was obtained,so that the instrument in sample analysis was in the best state,The correlation between the detection limit and the calibration curve is better than the requirements of the analysis method,so as to ensure good precision and accuracy of analysis results.