New approach to complex organic compounds mixtures analysis based on gas chromatography–atmospheric pressure photoionization–mass-spectrometry

The mass-spectra of a number of different hydrocarbons were obtained using atmospheric pressure photoionization (APPhI) and photochemical ionization (APPhCI) mass-spectrometry. The respective mass-spectra consisted mainly of molecular (M+) or quasimolecular (MH+) ion peaks or both. The composition of aromatic hydrocarbons in straight-run gasoline was investigated using standard PIONA method, based on capillary GC and retention time indexes, and GC/MS (APPhI). 56 aromatic hydrocarbons were identified using GC/MS (APPhI) and 43-using standard PIONA method. The opportunities of MS (APPHCI) for determination of impurities in pure hydrocarbons and for direct analysis of complex mixtures without separation were demonstrated when MS (APPhCI) analysis for GC standards of benzene and toluene was carried out (main component vapor was reagent gas). The targeted PAHs and phtalates were registered selectively in 44 component model mixture of semivolatiles with partial or without separation of the components, using GC/MS (APPhI).

► It was shown that APPhI or APPhCI mass-spectra of individual compounds consisted of M+ or MH+ ion peaks.
► Opportunity of complex mixtures GC/MS (APPhCI) analysis without separation was shown.
► Selective GC/MS (APPhI) determination of aromatic hydrocarbons in the straight-run gasoline.