Chemical Characterization of Polar Species in Colombian Vacuum Residue and Its Supercritical Fluid Extraction Subfractions Using Electrospray Ionization Ft-icr Mass Spectrometry

Abstract

Compositional changes of Colombian vacuum residue and its supercritical fluid extraction fractionation (SFEF) subfractions were analysed by positive- and negative mode electrospray (ESI) coupled with Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS). The results showed different distribution of compounds among the SFEF subfractions. The most dominant classes were the nitrogen compounds N1 and the SFEF end-cut showed to be enriched in multi-heteroatom species. Detailed analysis of double bond equivalent (DBE) distribution revealed that pyridine compounds were more aromatic than pyrrole ones. Planar limit indicated high condensation degree of carboxylic acids species. Therefore, this work evidenced the utility of SFEF fractionation and ESI FT-ICR MS in the detailed characterization of polar compounds in vacuum residua.