Characterization of Oxygenates, Nitrogenates, and Sulfonates in Shengli Lignite Extracts by Orbitrap Mass Spectrometry.

A series of carbon disulfide/acetone mixtures were used to extract organic species from Shengli lignite, a Chinese coal. Orbitrap mass spectrometry coupled with electrospray ionization was used to characterize the molecules in the extracts. Heteroatomic species, including oxygenates, nitrogenates, and sulfonates, were determined. Pure carbon disulfide or acetone had the lowest extraction for oxygenates while the mixtures increased the relative abundance of oxygenates. From the value of the double bond equivalence, the compounds with 1 oxygen contained the highest concentrations of aromatics and aliphatics, but compounds with 6 were aliphatic with a double bond equivalence of 3. For compounds containing 2 oxygens, aromatics with one ring were present at the highest concentrations in the 1:1 carbon disulfide:acetone extract. For compounds containing 3, 4, and 5 oxygens, most aromatic species were identified with double bond equivalence values between 4 and 6, showing the presence of an aromatic ring. The results indicated that the solvent mixtures enhanced the extraction of oxygenates from Shengli lignite. [ABSTRACT FROM PUBLISHER]