Resonance electron capture negative-ion mass spectrometry for analysis of petroleum and petroleum products: polysulfides

摘要

The structure of sulfide compounds in a product of catalytic thermal treatment of West Siberian mazut was examined by resonance electron Capture negative-ion mass spectrometry (REC NI MS) in combination with lowv-voltage positive-ion mass spectrometry (PI MS). A series of intense peaks of negative S_n~--ions (n = 1.6) were detected in a petroleum sample by REC NI MS; these peaks are indicative of the presence of polysulfides in the sample. The structure of tile above compounds can be determined from special features of REC NI mass spectra of the petroleum product. A comparison of REC NI mass spectra and PI mass spectra of the same sample indicates that, in the PI mass Spectra, these sulfide compounds are masked by aromatic hydrocarbons of the same molecular mass.