title: Identification of water-soluble heavy crude oil organic-acids, bases, and neutrals by electrospray ionization and field desorption ionization fourier transform ion cyclotron resonance mass spectrometry.
abstract: We identify water-soluble (23 degrees C) crude oil NSO nonvolatile acidic, basic, and neutral crude oil hydrocarbons by negative-ion ESI and continuous flow FD FT-ICR MS at an average mass resolving power, m/deltam50% = 550,000. Of the 7000+ singly charged acidic species identified in South American crude oil, surprisingly, many are water-soluble, and much more so in pure water than in seawater. The truncated m/z distributions for water-soluble components exhibit preferential molecular weight, size, and heteroatom class influences on hydrocarbon solubility. Acidic water-soluble heteroatomic classes detected at >1% relative abundance include O, O2, O3, O4, OS, O2S, O3S, O4S, NO2, NO3, and NO4. Parent oil class abundance does not directly relate to abundance in the water-soluble fraction. Acidic oxygen-containing classes are most prevalent in the water-solubles, whereas acidic nitrogen-containing species are least soluble. In contrast to acidic nitrogen-containing heteroatomic classes, basic nitrogen classes are water-soluble. Water-soluble heteroatomic basic classes detected at >1% relative abundance include N, NO, NO2, NS, NS2, NOS, NO2S, N2, N2O, N2O2, OS, O2S, and O2S2.
authors.affiliation: National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive, Tallahassee, FL 32310-4005, USA.
authors.forename: Lateefah A
authors.initials: LA
authors.lastname: Stanford
authors.forename: Sunghwan
authors.initials: S
authors.lastname: Kim
authors.forename: Geoffrey C
authors.initials: GC
authors.lastname: Klein
authors.forename: Donald F
authors.initials: DF
authors.lastname: Smith
authors.forename: Ryan P
authors.initials: RP
authors.lastname: Rodgers
authors.forename: Alan G
authors.initials: AG
authors.lastname: Marshall
mesh_terms: D000143:Acids / Q000737:chemistry; D017357:Cyclotrons / Q000295:instrumentation*; D005583:Fourier Analysis; D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation* / Q000379:methods*; D015394:Molecular Structure; D010578:Petroleum / Q000032:analysis*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry
chemical_list: D000143:Acids; D010578:Petroleum; D014874:Water Pollutants, Chemical; D014867:Water