微波消解-石墨炉原子吸收法测定复杂油脂样品中铅(Pb)含量

Determination of Lead in Complex Oil Samples by Graphite Furnace Atomic Absorption Spectrometry with Presses Microwave Digestion

针对混合油脂成分较多、杂质干扰大的特点,新建了微波消解-石墨炉原子吸收光谱法测定混合型复杂油脂样品中铅(Pb)含量的方法。通过对石墨炉条件进行优化,获得其最佳条件:基体改进剂体系为3μL磷酸二氢铵(1%)/硝酸镁(0.05%)混合溶液,灰化温度550℃,原子化温度1700℃。方法性能考察结果:在0~80μg/L范围内,所建方法的线性方程为y=0.0028x-0.0002,相关系数r^(2)=0.9979,加标回收率范围为95.5%~103.4%,RSD%范围为0.31%~2.13%(n=5),表明方法的线性良好,具有较高的准确度和精密度。采用所建方法测定了8种油脂样品中Pb的含量,测定结果表明:所建方法可以准确测定复杂油脂样品中Pb元素的含量。

Aim at the characteristics of mixed oils with more components and large interference from impurities,A method for the determination of lead in complex oil samples by graphite furnace atomic absorption spectrometry with pressure microwave digestion was developed.The optimum conditions of graphite furnace were obtained that the matrix modifier was 3μL mixed solution of NH_(4)H_(2)PO_(4)(1%)/Mg(NO_(3))_(2)(0.05%),the ash temperature set to 550℃and an atomization temperature set to 1700℃.The results of performance test were as follow:in concentration range of 0~80μg/L,the linear equation is y=0.0028x-0.0002 which r^(2)was 0.9979,and the range of standard recovery rate was 95.5%~103.4%,and the relative standard deviation(RSD%)was 0.31%~2.13%(n=5).These results of performance test showed that the built method had a good linear relationship with high accuracy and precision.The proposed method was used to analyze the lead content of 8 oil samples,and the practical results showed that the proposed method can accurately determine the content of Pb element in complex oil samples.