GC/MS ANALYSIS OF ORGANIC COMPOUNDS IN HOT WATER-EXTRACTABLE FRACTION FROM SHENFU COAL

摘要

So for, a number of researchers [1-6] have paid their attention to thermal treatment of coals in water. Braff and Brandes [1] investigated coal modification by supercritical steam. They found that exposure of Illinois No. 6 coal to 5 MPa of steam at temperatures between 320 and 360 ℃ resulted in significantly changes in the coal, i.e, the coal was depolymerized by the steam exposure. Subsequent work [3] suggested that the steam-treated coal became more hydrophilic due to the reaction of steam with the ether linkages in the coal, which forms hydrooxyl groups. Afterwards, this suggestion was confirmed by a model reaction [4]. C~(13) NMR and FTMS analyses showed that extract of steam-treated coal contained significant amounts of oxygenated compounds, including dihydroxyl aromatics [2]. Lino et al. [5] suggested that the increase in solubility in some organic solvents for three Argonne Premium coals by water treatment at 327 ℃ might be ascribed to the relaxation of hydrogen bonds and the removal of oxygen functional groups, including the cleavage of ether bonds. Shui et al. [5] recently reported that the enhancement in solubitity in carbon disulfide/N-methyl-2-pyrrolidinone mixed solvent by thermal treatment of four Chinese bituminous coals with water at 150 and 240 ℃ was related to the decreases of total oxygen and hydroxyl oxygen.