title: Selective Analysis of Sulfur-Containing Species in a Heavy Crude Oil by Deuterium Labeling Reactions and Ultrahigh Resolution Mass Spectrometry.
abstract: A heavy crude oil has been treated with deuterated alkylating reagents (CD₃I and C₂D₅I) and directly analyzed without any prior fractionation and chromatographic separation by high-field Orbitrap Fourier Transform Mass Spectrometry (FTMS) and Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS) using electrospray ionization (ESI). The reaction of a polycyclic aromatic sulfur heterocycles (PASHs) dibenzothiophene (DBT), in the presence of silver tetrafluoroborate (AgBF₄) with ethyl iodide (C₂H₅I) in anhydrous dichloroethane (DCE) was optimized as a sample reaction to study heavy crude oil mixtures, and the reaction yield was monitored and determined by proton nuclear magnetic resonance spectroscopy (¹H-NMR). The obtained conditions were then applied to a mixture of standard aromatic CH-, N-, O- and S-containing compounds and then a heavy crude oil, and only sulfur-containing compounds were selectively alkylated. The deuterium labeled alkylating reagents, iodomethane-d₃ (CD₃I) and iodoethane-d₅ (C₂D₅I), were employed to the alkylation of heavy crude oil to selectively differentiate the tagged sulfur species from the original crude oil.
authors.affiliation: Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany. wxuxiao@mpi-muelheim.mpg.de.
authors.forename: Xuxiao
authors.initials: X
authors.lastname: Wang
authors.affiliation: Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany. wschrader@mpi-muelheim.mpg.de.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schrader
mesh_terms: D003903:Deuterium / Q000737:chemistry*; D007553:Isotope Labeling / Q000379:methods*; D008745:Methylation; D010578:Petroleum / Q000032:analysis*; D066244:Proton Magnetic Resonance Spectroscopy; D012015:Reference Standards; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013455:Sulfur / Q000032:analysis*; D013876:Thiophenes / Q000737:chemistry
chemical_list: D010578:Petroleum; D013876:Thiophenes; D013455:Sulfur; D003903:Deuterium; C016366:dibenzothiophene
keywords: crude oil; deuterium labeling; mass spectrometry; selective analysis; sulfur; ultrahigh resolution