氧弹分解冷原子吸收法测定固体生物质燃料中汞含量

Determination of mercury in solid biofuels by oxygen bomb decomposition-cold atomic absorption spectrometry

对氧弹分解-冷原子吸收法测定固体生物质燃料中汞的方法进行研究,可为其在固体生物质燃料检测领域的推广应用奠定基础。简要介绍了氧弹分解及样品溶液测定的方法,从标准工作曲线、称样量及样品溶液量选择、擦镜纸的汞含量扣除、空白值的影响以及回收率等方面对采用氧弹分解-冷原子吸收法测定固体生物质燃料中汞的方法条件进行探索。试验中将样品称样量扩大到2.0 g±0.1 mg,将样品溶液定容至50 mL;通过包纸法解决了生物质样品易喷溅的问题;样品分解前,通过使用10%稀硝酸溶液对燃烧皿、氧弹、容量瓶等容器浸泡10 min,消除了容器空白值的影响;标准工作曲线线性相关系数为0.996;生物质样品加标回收率为86.80%~100.20%;采用氧弹分解-冷原子吸收法和直接测汞仪法同时测定11种生物质样品,F检验结果表明,2种方法的精密度无显著性差异;t检验结果表明,2种方法的测定结果无显著性差异,2种方法可以相互替代。氧弹分解-冷原子吸收法具有操作简单、处理时间短、设备成本低等特点,可用于固体生物质燃料中汞的测定。

Determination of mercury in solid biofuels by oxygen bomb decomposition-cold atomic absorption spectrometry was studied,which could lay a foundation for its popularization and application in the field of solid biofuels detection.The methods of oxygen bomb decomposition and sample solution determination were briefly introduced.The method conditions for the determination of mercury were explored from aspects such as standard working curve,selection of sample weight and sample solution,deduction of mercury content in mirror cleaning paper,influence of blank value and recovery rate.In the study,the sample weight was expanded to 2.0 g±0.1 mg,and the sample solution was made up to 50 mL.The problem of easy splashing of biomass samples was solved by wrapping paper.Before sample decomposition,10%dilute nitric acid solution was used to soak containers such as combustion vessels,oxygen bombs and volumetric flasks for 10 min,thus the influence of container blank value was eliminated.The linear correlation coefficient of the standard working curve is 0.996.The standard addition recovery rate of biomass samples is 86.80%~100.20%;11 kinds of biomass samples were simultaneously determined by oxygen bomb decomposition-cold atomic absorption spectrometry and direct mercury detector,the F test results show that there is no significant difference for precision of the two methods.The t test results show that there is no significant difference between the two methods,and the two methods can be substituted for each other.The oxygen bomb decomposition-cold atomic absorption method has the advantages of simple operation,short treatment time,low equipment cost,etc.,and it can be used for the determination of mercury in solid biofuels.