GC-MS Determination of 55 Aromatics in Hydrogen-Donor Solvent for Direct Coal Liquefaction

The sample of hydrogen-donor solvent for direct coal liquefaction was treated by SPE and eluted with different eluants to separate the components into 3 parts, i.e. alkanes, aromatics and glue. Through GC separation for the aromatics on weakly polar capillary chromatographic column, a TIC chromatogram of 55 aromatics was obtained with their peaks appeared in the order of their boiling points from lower values to higher values. On the base of the GC data, searchings were made successively into NIST spectra data base, the data base of standard spectra, and the data base of boiling points in ASPEN PLUS, and with the reference to researches on the retention indexes. Finally, the 55 compounds were recognized clearly, with their retention indexes on the HP-5MS chromatographic column calculated. Structural formula and values of relative molecular mass of these compounds were determined by the hyphenation of high resolution GC and MS. Quantification of the 55 compounds was performed by normalization of areas, and their relative contents were found. Carbon numbers of these aromatics were mainly in the range of C₁₀ to C₁₆, attaining to 92.20% of the total of the aromatics. These aromatics were mainly dropping into the category of cycloalkylbenzenes (46.87%), and secondly into the categories of dicycloalkylbenzenes and acenaphthenes (19.13% and 10.67% respectively).