Publication Date: Sat Sep 01 00:00: Research Org.: Oklahoma State Univ., Stillwater (USA).
Thus, detailed molecular analysis is a prerequisite for the correct assessment of (1) reaction conditions and catalyst on the mechanism and kinetics of coal liquefaction and (2) alteration in process conditions on the quality of the coal liquid.Īuthors: Benson, P. Although oils and asphaltenes are generally considered to be key intermediates in coal liquefaction, our results show that simple solvent extraction produces compositionally nonunique fractions. Furthermore, the overlap in compositions is appreciable. However, compound types are observed in both fractions which are equivalent in molecular formula and, hence, assumably in molecular structure. The asphaltenes contain higher molecular weight Z series, higher molecular weight homologs and different compound types than do the oils. Excellent agreement exists between the MS analyses. Carbon-number distributions for the aromatic concentrates were obtained using high- and low-resolution FI/MS and high-resolution 70-eV EI/MS and ultra high-resolution low-voltage EI/MS. Infrared spectra of the aromatic concentrates identified functional groups. Anion- and cation-exchange chromatography fractionated the oils and asphaltenes into acids, bases, and neutrals silica-gel chromatography separated neutral fractions into saturate and aromatic concentrates. A COED liquid was separated into oils, asphaltenes, and residue.