The structure of preasphaltene derived from Victorian brown coal during liquefaction was investigated by GPC analysis etc. These analyses make clear that the preasphaltene consists of three components; polar-higher molecuar weight (PH), polar-lower molecular weight (PL) and non-polar (NP) components. At the first stage of liquefaction reaction, the preasphaltene which includes much PH is produced, then it is converted into other lighter fractions such as asphaltene (others) through two main reaction paths as follows; (1) PH→others, (2) PH→PL→NP→others.
