催化热解-全自动测汞仪直接测定土壤中的总汞

Determination of Total Mercury in Soil by Catalytic Pyrolysis-Automatic Mercury Analyzer

为优化HJ923-2017测定土壤中总汞的方法,探索了测汞仪分析土壤最优仪器条件,研究了3种不同曲线制作方法对土壤中总汞测定的影响,并验证了优化方法的检出限、精密度和准确度。结果表明:在干燥温度300℃,干燥时间70 s,热裂解温度800℃,裂解时间为150 s仪器条件下,标准土校准曲线线性优于汞标液校准曲线,标准土校准曲线测得土壤结果准确度与精密度均符合国家标准要求。催化热解-全自动测汞仪优化方法可直接测定土壤中的总汞,测试过程不涉及样品前处理,兼具土壤分析的时效性和经济性,能同时满足常规实验室测试分析和应急监测中土壤中汞含量的测定。

A method for determination of total mercury in soil was established which optimized the environmental monitoring standard HJ923-2017. The optimal instrument conditions of mercury analyzer and the influence of three different curve making methods were explored on the determination of mercury in soil. The detection limit, precision and accuracy of the method were verified with this optimization method. The results showed that: under the condition of drying temperature 300℃ for 70s, and decomposition temperature 800℃ for 150s, the accuracy and precision of the soil measurement by standard soil-calibration curve can meet the national standard requirements which was better than the method of mercury standard solution calibration curve. The optimized method for determination of total mercury in soil can simultaneously meet the requirements of conventional laboratory test analysis and emergency monitoring, which has the advantages of timeliness and economy and no need for complicated sample pretreatment process.