采用石墨炉原子吸收光谱法,直接测定了电子级二乙二醇甲醚(DGME)中的Pb含量。对吸收谱线、基体改进剂、仪器分析条件如灰化温度、原子化温度等进行了研究。分析线选择283.3 nm,以25 g/L草酸加10 g/L NH4H2PO4溶液作复合基体改进剂,灰化温度800℃,原子化温度1400℃,线性方程为y=0.0066ρ(μg/L)+0.0715,相关系数R=0.9961。方法相对标准偏差〈3.7%,检出限为0.144 ng/m L。
The rapid and direct determination of trace Pb in electronic grade diethylene glycol monomethyl ether by graphite furnace atomic absorption spectrometry using standard addition method under the best matrix modifier selected has been developed. The analysis line,matrix modifier,and instrument analysis conditions such as ashing temperature,atomization temperature etc. were studied. In addition,the precision and the recovery of the experiment were determined in the paper. The results are as follows: Analysis line is 283. 3 nm,and 25 g / L oxalic acid and 10 g / L phosphate dibasic ammonium as matrix modifier was the best of all. Besides,the background absorption is relatively low. The optimal ashing temperature and atomization temperature were 800℃and 1400℃ respectively. The linear relationship is good and the regression equation is y = 0. 0066ρ + 0. 0715( R2= 0. 9961). The relative standard deviation range of the method was〈 3. 7%. The limit of quantification( LOQ) is 0. 144 ng /m L. The accuracy and precision of graphite furnace atomic absorption spectrometry method for determination of Pb are satisfactory.