Separation method for coal-derived solids and heavy liquids

A rapid, simple chromatographic procedure was developed to fractionate coal-derived solids and liquids for subsequent analysis by gas chromatography and mass spectrometry. The sample is dissolved in chloroform or tetrahydrofuran and is then preadsorbed on neutral alumina (activity l), and eluted with hexane, toluene, two fractions of chloroform, and a 9:1 mixture of tetrahydrofuran-ethanol. The principal compound types eluted in each fraction, respectively, are: saturated hydrocarbons, aromatic hydrocarbons and benzofurans, ethers, nitrogen compounds, and hydroxyl compounds. Vaporization of the solvent leaves the isolated fraction for further analysis. The procedure was applied to a wide variety of coal-derived solids and liquids including coal liquefaction products, coal tar distillates, solvent refined coal, solvent refined lignite, and tar from a slagging gasifier. In all cases studied, the same compound types were observed in the fractions obtained and the behavior on the columeatere integrated closely with MS or GC/MS. These trapped compounds are believed to be products and residuals of the original coalificans towards a more compl features displaying 'wave-like' and 'fork-like' shapes.