Characterization of coals, other kerogens, and their extracts by thermal mass spectrometry

摘要

The objective of this study is to elucidate the nature of the medium size molecules derived from coals by a succession of stronger extraction conditions. The Argonne Premium Coals have been extracted with pyridine, binary solvents and with KOH/ethylene glycol at 250 C. Thermal desorption and pyrolysis mass spectrometry were the major approaches chosen to provide detailed information on structure and heteroatom composition. Soft ionization techniques including desorption chemical ionization (DCI) and fast atom bombardment (FAB) were combined with high resolution and tandem MS techniques. This paper will focus on the comparison of the nature of the unextracted coals, the pyridine extract and the extracted coal residue. With this approach the desorption-pyrolysis yields of the extracts and residues combined were greater than the yields from the starting material. Although molecule weight distributions had a monitor dependence on rank, the nature of molecules with the same nominal mass varied greatly with rank. (ERA citation 17:015035)