Thermal Drying Methods on Coal Liquefaction Conversion

The sample coal used in this work was lignite containing 25% of moisture and 19% of ash from Canada. Drying of lignite coal had considerable influence on the coal liquefaction conversion. Vacuum dried and nitrogen dried samples provided higher conversion than air dried samples. The air drying showed nearly lower conversion, which probably as a result of oxidation. Air Drying seems to add oxidation to form more oxygen functional groups which increases the cross-linking reactions in the early stages of liquefaction. Among three thermal drying methods, vacuum dry provided highest conversion. It was expressed that coal sample with lower amount of moisture revealed higher conversion. Both temperatures and drying times seem to be key variables which impacted coal liquefaction conversion.