Abstract
Effects of the pre-heat treatment of coal paste, which is the mean of removal of oxygen functional groups and water contained in low rank coals on the properties of coal and on the liquefaction were examined.
The following results were obtained; (1) the preheat treatment at temperatures from 250 to 300°C was found to have the possibility in a decarboxylation and the elimination of water without decreasing the conversion at the liquefaction.(2) the results in the treatment at temperatures above 350°C suggested the degradation and polymeri-zation of organic parts in coals.(3) in the case of Yallourn coal, the treatment gave a higher conversion, which was due to the elimination of water bearing poisoning effect on the liquefaction.
