ADVANCES IN THE QUANTITATIVE SPECIATION OF PETROLEUM HEAVY ENDS:IMPLICATIONS FOR MARINE FUELS

摘要

This report describes a new method for the detailed characterization of petroleum heavy ends.Conventional bulk tests are combined with advanced testing methods,namely Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) with atmospheric pressure photon ionization (APPI),to characterize high-and non-boiling petroleum fractions in order to produce semi-quantitative,molecular-1evel data.The new method yields comparable results to a quantitative group type analysis by GCxGC,when applied to lighter,gas chromatography amenable fractions,and matches the compositional trends observed using various analytical techniques across fractions spanning the entire boiling range of a petroleum crude oil.The new analytical method is then applied to characterize in detail a vacuum residue treatment experiment targeting the generation of a heavy fuel oil with IMO 2020 compliant sulfur level.Detailed compositional trends are described following each process step,namely de-asphalting followed by successive hydrotreating,and show the removal of aromatic sulfur compounds with two and three thiophene rings.After reducing the total sulfur content to below 0.5 wt% the least reactive remaining sulfur species are tri-and tetra-cyclic aromatic mono-sulfur compounds,likely alkylated dibenzothiophenes and benzonaphthothiophenes.The formation of aromatic and saturated hydrocarbons is also evidenced by the presented approach.