气相色谱-飞行时间质谱联用法走航测定空气中挥发性有机物

Determination of VOCs based on TOFMS/GC-MS cruise monitoring

建立气相色谱-飞行时间质谱联用走航测定空气中挥发性有机物的方法。应用该方法对TO-14标准气体进行测定,各组分的含量在1.00~20.0 nL/L的范围内线性关系良好,相关系数均大于0.995。各组分检出限为0.2~0.7 nL/L,加标回收率为74.1%~108%,测定结果的相对标准偏差为2.5%~15.5%(n=6)。该方法满足现场快速、准确测定空气中VOCs含量的技术要求。基于该方法对区域环境空气中的VOCs物质种类及浓度水平进行定性、定量分析,结合气象参数及资料调研结果,可总结重点监控对象排放VOCs的特征污染物和排放规律,为追踪重点企业污染气体来源、加深对工业企业源大气污染分布特征和输送规律的认识提供科学的数据支撑。

TOFMS/GC-MS method for the cruise monitoring of volatile organic compounds in air was established.The standard gas of TO-14 was determined by this method,and the linearity of each component was good in the range of 1.00-20.0 nL/L with the correlation coefficient all more than 0.995.The detection limits of all components were 0.2-0.7 nL/L,the recovery rates were 74.1%-108%,and the relative standard deviations of the determination result were 2.5%-15.5%(n=6).The method could quickly and accurately meet the measurement requirements for VOCs contents in air.Based on this method,the types and concentration levels of VOCs in the ambient air were analyzed qualitatively and quantitatively.Combined with the meteorological parameters and data research results,the characteristic pollutants and emission laws of VOCs emitted by enterprises were found out,which could be used to track the sources of pollution gases of key enterprises and deepen the recognition of the distribution characteristics and transportation laws of air pollution from industrial enterprises knowledge provides scientific data support.