工作场所空气中痕量重金属速测方法的研究
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摘要
目的:建立一种快速消解并同时测定工作场所空气中痕量重金属钴(Co)﹑铜(Cu)﹑铅(Pb)﹑镍(Ni)、镉(Cd)﹑锌(Zn)的方法。
方法:采用微波消解法,在180℃﹑20atm﹑800w条件下消解采样滤膜;用壳聚糖在消解溶液pH=5.0,室温(20~30℃)条件下富集,直接火焰原子法测定富集消解液中痕量重金属Co﹑Cu﹑Pb﹑Ni、Cd﹑Zn。
结果:微波消解法与混酸消解法相对标准偏差(RSD)范围分别为3.0%~12.7%和6.7%~22%,微波消解法RSD明显低于混酸消解法,说明微波消解法精密度好于混酸法;Co﹑Cu﹑Pb﹑Ni、Cd﹑Zn检出限分别为4.85、2.42、3.17、5.47、0.42、0.51ng/ml;标准曲线回归系数(r)范围为0.999 1~0.999 9;回收率范围为91.3%~108.4%;用标准物质(GBW08401)进行质控测试,分析结果与标准值吻合;样品测定值与石墨炉原子法相比,无显著性差异(P﹥0.05)。
结论:该方法简便、快速、准确、灵敏度高,适合工作场所空气中痕量重金属Co﹑Cu﹑Pb﹑Ni、Cd﹑Zn的测定。
Objective:To find a method of digesting membranes rapidly and simultaneously determining trace heavy metals of Pb, Cd, Cu, Co, Ni and Zn in the air of workplaces.
Methods: In the paper, trace heavy metals of Pb, Cd, Cu, Co, Ni and Zn in the the air of workplaces were pretreated by microwave digestion (at 180℃, 20atm , 800w) and concentrated by absorption on chitosan (at pH = 5.0, 20℃~30℃),Determined Co, Cu, Pb , Ni, Cd and Zn in digesting liquids with direct flame atomic absorption spectrophotometry.
Results: Microwave digestion relative standard deviation (RSD) range of 3.0% ~12.7% was significantly higher than mixed acid method of 6.7%~22%, indicated good precision compared with the mixed acid method; The detection limit of this method was 3.17ng/ml for Pb, 0.42 ng/ml for Cd , 2.42 ng/ml for Cu, 4.85 ng/ml for Co, 5.47ng/ml for Ni and 0.51ng/ml for Zn;Standard linear correlation (r) were of the range 0.9991~0.9999; Recovery ratio were of the range 91.3%~108.4%; The standard reference materials was used as quality control standards and the analysis results conformed well to the certified values, the sample results have no significance different(P﹥0.05)compared with graphite furnace atomic absorption spectyometry.
Conclusion: The method was simple, rapid , accurate and highly sensitive. It was suitable for determining trace heavy metals of Pb, Cd, Cu, Co, Ni and Zn in the air of workplaces.
方法:采用微波消解法,在180℃﹑20atm﹑800w条件下消解采样滤膜;用壳聚糖在消解溶液pH=5.0,室温(20~30℃)条件下富集,直接火焰原子法测定富集消解液中痕量重金属Co﹑Cu﹑Pb﹑Ni、Cd﹑Zn。
结果:微波消解法与混酸消解法相对标准偏差(RSD)范围分别为3.0%~12.7%和6.7%~22%,微波消解法RSD明显低于混酸消解法,说明微波消解法精密度好于混酸法;Co﹑Cu﹑Pb﹑Ni、Cd﹑Zn检出限分别为4.85、2.42、3.17、5.47、0.42、0.51ng/ml;标准曲线回归系数(r)范围为0.999 1~0.999 9;回收率范围为91.3%~108.4%;用标准物质(GBW08401)进行质控测试,分析结果与标准值吻合;样品测定值与石墨炉原子法相比,无显著性差异(P﹥0.05)。
结论:该方法简便、快速、准确、灵敏度高,适合工作场所空气中痕量重金属Co﹑Cu﹑Pb﹑Ni、Cd﹑Zn的测定。
Objective:To find a method of digesting membranes rapidly and simultaneously determining trace heavy metals of Pb, Cd, Cu, Co, Ni and Zn in the air of workplaces.
Methods: In the paper, trace heavy metals of Pb, Cd, Cu, Co, Ni and Zn in the the air of workplaces were pretreated by microwave digestion (at 180℃, 20atm , 800w) and concentrated by absorption on chitosan (at pH = 5.0, 20℃~30℃),Determined Co, Cu, Pb , Ni, Cd and Zn in digesting liquids with direct flame atomic absorption spectrophotometry.
Results: Microwave digestion relative standard deviation (RSD) range of 3.0% ~12.7% was significantly higher than mixed acid method of 6.7%~22%, indicated good precision compared with the mixed acid method; The detection limit of this method was 3.17ng/ml for Pb, 0.42 ng/ml for Cd , 2.42 ng/ml for Cu, 4.85 ng/ml for Co, 5.47ng/ml for Ni and 0.51ng/ml for Zn;Standard linear correlation (r) were of the range 0.9991~0.9999; Recovery ratio were of the range 91.3%~108.4%; The standard reference materials was used as quality control standards and the analysis results conformed well to the certified values, the sample results have no significance different(P﹥0.05)compared with graphite furnace atomic absorption spectyometry.
Conclusion: The method was simple, rapid , accurate and highly sensitive. It was suitable for determining trace heavy metals of Pb, Cd, Cu, Co, Ni and Zn in the air of workplaces.
引文
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[9] Ruiz M ,Sastre A,Guibal E.Separation Sci Techn,2002,37(10) :2385
[10]谢华林,张萍,蒋宏伟等.大气颗粒物中重金属元素在不同粒径上的形态分析[J].环境工程,2002,20(6):55-57.
[11] Mohanral R,Azeez P A,Priscilla T,et a1.Heavy metal in airborne particulate matter of urban Coimbatore[J].Environmental Contamination and Toxicology,2004,47:162-167.
[12]吕昌银.毋福海.空气理化检验[M].北京:人民卫生出版社,2006:15.
[13]李晓,杨立中.成都市东郊TSP及Pb、Cd、Hg、As浓度日变化规律研究[J].地质灾害与环境保护,2004,15(3):35-38.
[14]于燕,张振军,李义平.西安市大气颗粒物污染现状及其金属特征研究[J].环境与健康杂志,2003,20(6):359-360.
[15]王章玮,张晓山,张逸等.北京市大气颗粒物PM2.5、PM10及降雪中的汞[J].环境化学,2004,23(6):668-673.
[16]沈轶,陈立民,孙久宽等.上海市大气PM2.5中Cu、Zn、Pb、As等元素的浓度特征[J].复旦大学学报,2002,41(4):405-408.
[17]赵美萍,邵敏.环境化学[M].北京:北京大学出版社.2005:186.
[18]钱嫦萍,陈振楼,毕春娟等.潮滩沉积物重金属生物地球化学研究进展[J].环境科学研究,2002,15:49-51.
[19] Wang S X,Zhang S Z,Shan X Q,et a1.Fractionation of heavy metals in different particle-size sediments and its relationship with heavy metal pollution[J].Environmental Contamination and Toxicology,2003.71:873-880.
[20] Tessier A,Campbell P R C ,Bisson M ,et a1.Sequential extraction procedure for the speciation of particulate tracemetal[J].Analytical Chemistry,1979,51:850-851.
[21]陈子金.工作场所中重金属存在形式探索[J].中国卫生检验杂志,1995(特刊):172-174.
[22]齐文启,陈光,孙宗光等.大气颗粒物监测分析及今后研究课题[J].中国环境监测,2003,19(1):51-62.
[23]王荫淞,李爱国,魏仑等.用X射线吸收近边结构谱研究大气颗粒物中元素的种态[J].核技术,2004,27(11):810-813.
[24]陶俊,陈刚才,赵琦等.重庆市大气TSP中重金属分布特征[J].重庆环境科学,2003,25(12):15-19.
[25]张元勋,王荫淞,李德禄等.上海冬季大气可吸入颗粒物的PIXE研究[J].中国环境科学,2005,25(增刊):1-5.
[26] Horacio B,Marcelo O.Study of atmospheric particulate matter in Buenos Aires city[J].Atmospheric Environment,2003,37:1135-1147.
[27]孙微,王磊,李一峻等.电化学分析方法在元素形态分析中的应用[J].分析化学,2004,32(4):541-545.
[28] GBZ/T 160—2004《工作场所空气有毒物质测定》[S].
[29] GBZ/T 192.1—2007工作场所空气中粉尘测定[S].
[30]张伶,黄开宇,张吉广.微波消解石墨炉原子吸收法测定空气中的锰(铅)[J].2002,1:44.
[31]但德忠,徐先顺,罗方若等.现代微波制作技术[M].成都:四川大学出版社,2003:61,72.
[32]张加玲.卫生化学[M].北京:中国协和医科大学出版社,2003:34,213.
[33]高焰,王东海,林玉斌等.空气中铅镉超声浸取原子吸收方法研究[J].中国环境监测,2003,19(4):37.
[34]黄达卿,陈亮,弯军英等.壳聚糖对金属离子的吸附选择性[J].广州化工,2005,33(6):38.
[35]姚瑞华,孟范平,张龙军等.改性壳聚糖对重金属离子的吸附研究和应用进展[J].材料导报,2008,22(4):66.
[36]缪茜,孙静.壳聚糖吸附剂研究[J].北京工业职业技术学院学报,2004,3(3):25.
[37] JJF 1059—1999,测量不确定度评定与表示.北京:中国计量出版社.
[l]黄丽,李加新,周宁怀等.环境污染与防治,2001,23(5):24.
[2] Muzzarelli R A A Chitin.New York,Pergamon press,1977,134.
[3] Tseng R L,W u F C,Juang R S.J Chem Teehnol Blot,1999,74:533-538.
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