采用直接测汞仪快速测定煤中痕量汞.pdf

第1期
煤质技术
2014年1月
采用直接测汞仪怏速測定煤中痕量汞
张衡,高建文,王鑫焱',狄楠楠,康俊
(1秦皇岛出入境检验检疫局煤炭检测技术中心,河北秦皇岛066003;
2.秦皇岛市环境保护监站,河北秦皇岛06000)
摘要:结合DMA-80直接测汞仪的测定原理为样品燃娆、齐纳管吸附、冷蒸气原子吸收光谱,
建立了直接测汞仪快速测定煤中痕量汞的分析方法,探讨了煤炭测定中的样品制备、仪器測定条件
及其影响因素。实验结果表明:将直接测汞仪快速测定痕量汞的测定结果与电感耦合等离子体一原
子发射光谱法进行比較,两者间无统计学差异,其标准样品测定值与标称值吻合。不同汞含量水平
的煤炭样品测定结果相对标准偏差(RSD)不大于3.69%且2次重复性实验结果偏差优于国家检
验标准方法,可满足ISO检验标准方法的要求,即直接测汞仪法测定汞具有快速、准确且无需样
品预处理和无药品试剂污染等特点,适合煤炭样品中痕量汞的测定。
关鍵词:煤炭;汞;电子耦合等离子体一原子发射光语法;直接测汞法;精密度
中图分类号:TQ531;P618.68文献标识码:B文章编号:1007-7677(2014)01-0017-04
Rapid determination of trace mercury in coal by direct mercury analyzer
ZHANG Heng GAO Jian-wen, WANG Xin-yan, DI Nan-nan, KANG Jun
(1. Coal Inspection &Technique Center of Qinhuangdan Entry-exit Ins ection and Quarantine Bureau, Qinhuangdao 066003, China
2. Qinhuangdao Enuironmental Monitoring Station, Qinhuangdao 066000, China
Abstract: The determination principles of DMA-80 direct mercury analyzer were sample combustion, Zener diode absorption and
cold vapor atomic absorption spectrometry. Based on the principles above, in this paper, the rapid method for determination of
trace mercury in coal by the direct mercury analyzer was established. The sample preparation and the conditions of instrument and
other influencing factors were discussed as well. The experiments showed that: There was no significant difference between
determination results when using direct mercury analyzer and the inductively coupled plasma-atomic emission spectrometry
respectively. The measured values of standard sample were identical to the certified values. The RSD value of determination results
of coal samples with different mercury level was low than 3.69%. The deviation of twice repeated experiments was superior to GB
test standard, which could also meet the requirements of the ISO test standard. So using direct mercury analyzer to determine the
mercury had some merits such as high speed, good accuracy, no requirements of pre-processing of samples and no reagents
contamination, which made it suitable for determination of trace mercury in coal
Key words: coal; mercury: direct mercury analyzer; inductively coupled plasma-atomic emission spectrometry, direct mercury
determination; precision
0引言
法(GBT16659~-2008《煤中汞的测定方法》〉4
采用酸分解、冷蒸气原子吸收光谱法或基于原子荧
汞是煤炭中主要有害微量元素之一,具有较强光法原理的测汞仪测定媒炭中的汞;ISO检验标准
的挥发性,几乎所有的汞在煤燃烧过程中都会释放
方法(ISO15237:2003(E))?采用氧弹燃烧一冷
进入大气,对环境和人体健康产生危害。媟燃烧是
蒸气原子吸收光谱法测定煤炭中痕量汞。以上检测
大气中汞污染的重要来源之一山,近年来煤燃烧产方法都具有消耗试剂量大、处理时间长且消化过程
生的汞对环境造成的污染已引起世界许多国家的高中易引起污染等缺点。DMA-80直接测汞仪无需样
度重视2,3。
品处理,直接将样品送入仪器,在氧气流的负载下
对煤燃烧过程中汞的释放、迁移及转化过程的
样品被干燥,继而被热分解;热分解后的产物进入
机制进行系统、深入的研究,快速而准确地测定煤炭催化管催化还原,汞被还原成汞原子,汞蒸汽被齐
中的痕量汞具有重要的意义。现行国家标准检测方
化管收集进行完全金汞齐反应,随后高温解吸;最
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