水浴消解-原子荧光光谱法测定土壤中总砷和总汞

随着人类社会的发展,人为因素造成土壤重金属污染是当今世界越来越不容忽视的环境问题,其中以砷、汞最为突出。采用硝酸和盐酸混合液水浴消解土壤,硫脲和抗坏血酸作为还原剂,采用氢化物发生原子荧光光谱法测定总砷和总汞的含量。通过实验,砷、汞元素校正曲线相关系数分别为0.9996和0.9997,砷、汞方法检出限分别为0.010mg/kg和0.003mg/kg,相对标准偏差范围为1.52%～3.05%和1.21%～4.47%,表明该方法具有较好的准确性和稳定性,同时通过加标实验,砷、汞的加标回收率分别为95.5%～106.1%和93.4%～103.5%,进一步确认了该方法准确可靠。

Determination for Arsenic and Mercury in Soils using Water Bath Digestion Coupled with Atomic Fluorescence Spectrometry

Soil heavy metal pollution resulting from anthropogenic sources is a growing environmental problem that can not be ignored, among which arsenic and mercury is the most prominent. In this study,soil samples were pretreated by a mixture of nitric and hydrochloric acid in water bath, and the digestion liquid was used as the test liquid of mercury. The digestion liquid, which was add by hydrochloric acid solution and thiourea solution, was used as the test liquid of arsenic. The result showed that the correlation coefficient with calibration curve linearity of arsenic and mercury were 0.9996 and 0.9997 respectively.The respective detection limits of arsenic and mercury were 0.010 mg/kg and 0.003 mg/kg, and relative standard deviations( RSD) were 1.52% ～3.05% and 1.21% ～4.47%, the results proved that the method was accurate and stable. The accuracy of this method was further verified by recovery tests, the recoveries for arsenic and mercury were 95.5%～106.1% and 93.4～103.5%.