石墨炉原子吸收光谱法测定土壤中铅元素

Determination of Lead in Soil by Graphite Furnace Atomic Absorption Spectrometry

山西省是我国重要的能源和重化工基地,由于煤矿开采、工矿企业废水的排放,造成周边土壤铅污染较严重,因此,准确检测矿区周边的铅元素很有必要.本文通过优化试验条件,使用石墨炉原子吸收法测定土壤中的铅含量,比较了微波消解和电热板两种消解方法对土壤标准物质的消解效果,测定出吕梁市某矿区周边土壤铅元素的含量.实验表明:石墨炉原子吸收法采用电热板消解,加入混酸(6mL氢氟酸、2mL高氯酸、2mL浓硝酸),该方法操作便捷,时间短,消解完全,结果可靠.在优化条件下,对购买的土壤标准物质的测定结果在标准值范围内,同时检测出3个土壤样品的含铅量分别为67.11,67.11,67.12,加标回收率分别为102.2%,94.93%,92.95%.

Shanxi Province is an important energy and heavy chemical industry base in China.Due to the discharge of waste water from industrial and mining enterprises,the lead pollution in the surrounding soil is more serious.Therefore,it is necessary to accurately detect the lead elements around the mining area.The lead content in soils was determined by graphite furnace atomic absorption spectrometry and the effect of two kinds of digestion methods on soil standard material was compared.The content of lead in the soil around a mining area in Lvliang City was determined.Experiments show that the graphite furnace atomic absorption method using hot plate digestion,adding mixed acid（6 ml hydrofluoric acid,2 mL perchloric acid,2 mL concentrated nitric acid）has the advantages of convenient operation,short time,complete digestion and reliable results.Under the optimized conditions,the content of lead in three soil samples were detected within the range of the standard value of the purchased soil standard materials.The lead content was 67.11,67.11 and 67.12 respectively,and the recovery rate was102.2%,94.93% and 92.95%respectively.