痕量磷化氢的冷阱二次富集机理与GC/FID分析方法研究  

Mechanism of Two Stages Cold Trap Enrichment and the Analysis Method of GC / FID for Trace Phosphine

作　　者：魏爱书[1,2] 牛晓君[1,2] 王瑾丰 米丽娜[1,2] 闫新秀 

机构地区：[1]华南理工大学环境科学与能源学院,广东广州510006 [2]工业聚集区污染控制与生态修复教育部重点实验室广东广州510006

出　　处：《分析测试学报》2013年第10期1207-1211,共5页Journal of Instrumental Analysis

基　　金：国家自然科学基金资助项目(41071305)

摘　　要：将火焰离子化检测器(FID)应用于二次富集气相色谱检测中构建了冷阱二次富集-GC/FID系统检测环境中痕量磷化氢的分析方法。研究了冷阱温度、载气流量、柱温箱温度和检测器温度对该系统富集检测效果的影响,讨论了磷化氢富集的机理,并将该系统应用于广州地区典型水稻田环境中结合态磷化氢(MBP)的检测。结果表明:当冷阱温度为-90℃,载气流量为1.5 mL/min,柱温箱温度为90℃,检测器温度为220℃时,系统操作条件最优。冷阱二次富集磷化氢的主要机理是富集毛细管柱(KB-Al2O3/NaSO4)对磷化氢的吸附作用,属气-固吸附。系统检出限为0.041 7 pg,精密度为4.3%。整个水稻生长周期内,水稻土中结合态磷化氢(MBP)的平均含量为120.59 ng/kg,测定结果的相对标准偏差均值为8.5%。该方法对痕量磷化氢的检测效果与使用氮磷检测器(NPD)的传统方法相近,但FID检测器的结构简单、操作方便、价格经济,使环境中痕量磷化氢的检测更容易实现,可推广应用。An analytic system of two stages cold trap enrichment and GC/FID for the determination of trace phosphine in environment was developed,using flame ionization detector （FID）.The influences of cold trap temperature,carrier gas flow,column oven temperature and detector temperature on the enrichment and determination for phosphine were investigated.At the same time,the mechanism of phosphine enrichment was also discussed.In addition,the system was used to measure mixture bound phosphine（MBP） in the typical paddy fields in Guangzhou.As a result,the best operation condition was defined as follows：cold trap temperature：-90 ℃,carrier gas flow：1.5 mL/min,column oven temperature：90 ℃,and detector temperature：220 ℃.The main mechanism for the cold trap enrichment was the enrichment capillary＇s absorption to phosphine,belonging to gas-solid absorption.In the whole cycle of rice growth,the average concentration of mixture bound phosphine （MBP） was 120.59 ng/kg,with an average relative standard deviation （RSD） of 8.5％.With the detection limit of 0.041 7 pg and RSD of 4.3％,this system had a similar function for detecting phosphine to the traditional method with nitrogen phosphorus detector（NPD）.Owing to the simple constitution,easy operation and moderate price of FID,this system makes the analysis of trace phosphine easier,thus could be applied in lad generally.

关 键 词：磷化氢 GC FID 富集机理 

分 类 号：O657.71[理学—分析化学] O613.62[理学—化学]