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,*
aDept. 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
*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.