Distinguishing by Principal Component Analysis o-Xylene, m-Xylene, p-Xylene and Ethylbenzene Using Electron Ionization Mass Spectrometry

Abstract

The possibility of distinguishing between o-xylene, m-xylene, p-xylene and ethylbenzene on the basis of only their 70 eV electron ionization (EI) mass spectra has been investigated. These four isomers were distinguished by principal component analysis of respective EI mass spectra (recorded under identical conditions). The mass spectra considered contained either eleven or five m/z values, which had intensities greater than 5% or 10% of base peak, respectively.