REACTIONS OF BROWN COALS WITH CO/H2O IN THE PRESENCE OF SODIUM ALUMINATE

Reactions of some Victorian brown coals with CO/H2O in the presence of sodium aluminate in microautoclaves with rapid heat-up times have been shown to give very high conversions to products soluble in tetrahydrofuran (THF) under mild conditions (355-degrees-C, 3 MPa CO for 1 h). The influence of water loadings, of reaction time and temperature, of sodium aluminate concentration, of gas composition and of CO partial pressure have been investigated. In general, higher conversions were obtained than from reactions of the coal at 355-degrees-C in H-2/tetralin. Oil and asphaltol (THF-soluble, CH2Cl2-insoluble) yields were significantly higher for the CO/H2O than for the H-2/tetralin reactions. The structure of the products has been examined by spectroscopic and elemental analysis. The asphaltols from these CO/H2O reactions have been shown to have significantly different chemical structures to those from H-2/tetralin reactions.