Which Components of Crude Oil Dissolve in Water?

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Which Components of Crude Oil Dissolve in Water?
Lateefah Stanforda, Sunghwan Kimb, Geoffrey C.
Kleina, Donald F. Smitha, Ryan P. Rodgersa,c,,
and Alan G. Marshalla,c,
a Dept. of Chemistry and Biochemistry, Florida
State Univ., Tallahassee, FL 32306, USA b Korean
Basic Science Institute, 52 Yeoeun-Dong,
Yusung-Gu, Daejeon 305-333, Korea c ICR
Program, National High Magnetic Field Lab,
Tallahassee, Florida 32310-4005, USA
The first step in understanding petroleum
crude oil spills is to identify which chemical
components dissolve in water. Here, we use
ultrahigh-resolution magnet-based mass
spectrometry to resolve and identify, for the
first time, thousands of different chemical
components of crude oil and water exposed to that
oil. Of the 7,000 acidic species identified in
South American crude oil, surprisingly many are
water-soluble, and many more in pure water than
in seawater (see Figure. Top crude oil. Bottom
water-soluble components). Water solubility
depends on molecular weight, size, and heteroatom
(nitrogen, oxygen, sulfur) content. Acidic
oxygen-containing chemicals are most prevalent in
the water-solubles, whereas acidic
nitrogen-containing chemicals are least soluble.
In contrast, basic nitrogen-containing chemicals
are water-soluble. (Peaks noted with an asterisk
in the distilled water-soluble bases portion of
the Figure are nitrogen/oxygen/sulfur- containing
compounds too dilute to be detected in the parent
oil.) Possible structures are shown for two of
the chemical components. Supported by NSF
(DMR-00-84173), NHMFL, and Florida State
University.
Stanford, L.A. Kim, S. Klein, G.C. Smith,
D.F. Rodgers, R.P. and Marshall, A.G.,
Identification of Water-Soluble Heavy Crude Oil
Organics. Acidic and Basic NSO Compounds in Fresh
Water and Sea Water by Electrospray Ionization
Fourier Transform Ion Cyclotron Resonance Mass
Spectrometry, Environ. Sci. Technol. 2007, 41,
2696-2702.