Ion mobility spectrometry(IMS)is a very fast,highly sensitive,and inexpensive technique,it permits effcient monitoring ofvolatile organic compounds like alcohols.In this article,positive ion mobility spectra for six alcohol organic compounds have beensystematically studied for the first time using a high-resolution IMS apparatus equipped with a discharge ionization source.Utilizingprotonated water cluster ions(H2O)nH+as the reactant ions and clean air as the drift gas,alcohol organic compounds,ethanol,1-propanol,2-propanol,1-butanol,1-pentanol and 2-octanol,all exhibit product ion characteristic peaks in their respective ion mobilityspectrometry,that is a result of proton transfer reactions between the alcohols and reaction ions(H2O)nH+.The mixture of thesealcohols,including two isomers,has been detected,and the results showed that they could be distinguished effectively in the ionmobility spectrum.The reduced mobility values have been determined,which are in very well agreement with the traditional 63Ni-IMSexperimental values.The exponential dilution method was used to calibrate the alcohol concentrations,and a detection limit availablefor the alcohols is in order of magnitude of a few ng/L.
HAN Hai-yan HUANG Guo-dong JIN Shun-ping ZHENG Pei-chao XU Guo-hua LI Jian-quan WANG Hong-mei CHU Yan-nan
以《大气污染物综合排放标准))(GB 16297-1996)中有机物的实时在线测量为目的,对自行研制的质子转移反应质谱(proton transfer reaction mass spectrometry,PTR-MS)装置的参数进行了优化和测量。利用高纯N_2稀释的单一有机物PTR-MS测量结果表明,在E/N=144 Td条件下,质子化的有机物离子为主要的产物离子峰,没有明显的碎片离子存在。测试了进样系统中催化转化装置的性能,给出了11种挥发性有机物的探测灵敏度和检测下限,讨论了PTR-MS的测量精度。测试结果表明,自行研制的PTR-MS能够实时在线监测《大气污染物综合排放标准》中规定的有机污染物。
