土壤中铅镉的高压微波消解—三磁场塞曼石墨炉原子吸收光谱法

Lead and cadmium in the soil of the high-pressure microwave digestion-three magnetic field zeeman graphite furnace atomic absorption spectrometry

目的研究高压微波消解—三磁场塞曼测定土壤中的铅、镉。方法利用高压微波消解仪,用王水结合氢氟酸混合消解土壤,智能石墨赶酸仪赶酸,以磷酸二氢铵和硝酸镁作为混合基体改进剂,三磁场塞曼石墨炉原子吸收光谱法进行检测。结果 Pb在0～50μg/L线性范围内,相关系数为0.9 986,铅回收率93.0%～109.7%,铅的最低检出限的浓度为0.126μg/L;Cd在0～5μg/L线性范围内,相关系数为0.9 991,镉相对标准偏差在0.93%～4.73%之间,镉回收率在94.9%～101.25%之间,镉的最低检出限的浓度为0.0 096μg/L。结论高压微波消解—三磁场塞曼石墨炉原子吸收测定土壤中的铅镉具有灵敏度高、干扰少、选择性好、准确度高等优点。

Objective To study the zeeman high-pressure microwave digestion-three magnetic field for determination of lead and cadmium in soil. Methods High-pressure microwave digestion instrument were used with the combination of aqua regia and hydrofluoric acid mixture to dissolves soil; intelligent graphite squeezing equipment were used for evaporation. The three-magnetic field zeeman graphite furnace atomic absorption spectrometry was used to detect ammonium dihydrogen phosphate and magnesium nitrate as mixed matrix modifiers. Results Pb was in 0 ～ 50 μg/L linear range,the correlation coefficient beings0. 9 986,the lead recovery rate being 93. 0% ～ 109. 7%. The minimum detection limit of lead was 0. 126 μg/L; Cd was in 0 ～5 μg/L linear range,and correlation coefficient was 0. 9 991. The relative standard deviation of cadmium was 0. 93% ～ 4. 73%,and the cadmium recovery rate was 94. 9% ～ 101. 25%. The minimum detection limit of cadmium concentration was 0. 0 096 μg/L. Conclusion High-pressure microwave digestion-three magnetic field zeeman graphite furnace atomic absorption for determination of lead and cadmium in soil has advantages like high sensitivity,less interference,good selectivity,high accuracy,etc.