氢化物发生-电感耦合等离子体原子发射光谱法测定土壤中汞和砷  

Determination of mercury and arsenic in soil by hydride generation-inductively coupled plasma atomic emission spectrometry

作　　者：王记鲁 郝苗青 李静 王鑫 刘跃 WANG Jilu;HAO Miaoqing;LI Jing;WANG Xin;LIU Yue(Tianjin Eco-environmental Monitoring Center,Tianjin 300191,China;Tianjin Nankai Eco-environment Monitoring Center,Tianjin 300112,China)

机构地区：[1]天津市生态环境监测中心,天津300191 [2]天津市南开区生态环境监测中心,天津300112

出　　处：《冶金分析》2023年第5期74-78,共5页Metallurgical Analysis

摘　　要：汞和砷是土壤环境质量监测中的管控元素,由于两者含量差异较大,使用氢化物发生-原子荧光光谱法难以同时准确测定,而使用电感耦合等离子体原子发射光谱法(ICP-AES)测定砷、汞时有灵敏度偏低的问题。试验探讨了自制简易氢化物发生装置与电感耦合等离子体原子发射光谱仪联用同时测定土壤中汞和砷。使用王水(1+1)消解样品,保持样品溶液的酸度为15%,还原剂为15 g/L硼氢化钾溶液;设置ICP-AES最佳工作条件为入射功率1 450 W、蠕动泵转速1.7 mL/min、等离子体气流量16 L/min、雾化气流量0.45 L/min。方法中汞和砷的线性范围分别为0.50~10.0μg/L和5.00~100μg/L,线性相关系数均为0.999 8,检出限分别为0.016μg/g和0.12μg/g,定量限分别为0.064μg/g和0.48μg/g。按照实验方法测定土壤标准物质和实际土壤样品中汞和砷,土壤标准物质的测定值与认定值相一致;实际样品测定结果的相对标准偏差(RSD,n=6)为3.1%~4.8%。同时采用实验方法和原子荧光光谱法对实际土壤样品中汞和砷进行测定,并通过t检验法检验显示两种方法测定结果无显著性差异。表明方法适合土壤中汞和砷的同时测定。Mercury and arsenic belong to the controlled elements in soil environmental quality monitoring.Due to the great difference in content between two elements,it is difficult to accurately determine them simultaneously by hydride generation-atomic fluorescence spectrometry.If inductively coupled plasma atomic emission spectrometry(ICP-AES)are employed to determine arsenic and mercury,the problem is that the sensitivity is low.A simple hydride generation device combined with inductively coupled plasma atomic emission spectrometer(HG-ICP-AES)was self-made for the simultaneous determination of mercury and arsenic in soil.The soil sample was digested with aqua regia(1+1).The acidity of sample solution was kept at 15%containing 15 g/L potassium borohydride as the reducing agent.The optimal working conditions of ICP-AES were as follows:the incident power was 1450 W,the peristaltic pump speed was 1.7 mL/min,the plasma gas flow was 16 L/min,and the atomizing gas flow was 0.45 L/min.The linear range of mercury and arsenic was 0.50-10.0μg/L and 5.00-100μg/L,respectively.The linear correlation coefficients were both 0.9998.The limits of detection of mercury and arsenic were 0.016μg/g and 0.12μg/g,and limits of quantification were 0.064μg/g and 0.48μg/g,respectively.The contents of mercury and arsenic in certified reference materials and actual samples of soil were determined according to the experimental method.The measured values of reference materials were consistent with the certified values.The relative standard deviations(RSD,n=6)of determination results for the actual sample were between 3.1%and 4.8%.Meanwhile,the contents of mercury and arsenic in actual sample of soil were determined according to the experimental method and atomic fluorescence spectrometry.The t test indicated that the determination results of two methods had no significant difference.The proposed method was suitable for the simultaneous determination of mercury and arsenic in soil.

关 键 词：氢化物发生-电感耦合等离子体原子发射光谱法(HG-ICP-AES) 土壤 汞 砷 

分 类 号：O657.31[理学—分析化学] X53[理学—化学] X833[环境科学与工程—环境工程]