Name : The 56th Conference of Coal Science
Number : 56
Location : [in Japanese]
Date : October 29, 2019 - October 30, 2019
Pages 70-71
A subbituminous coal was treated with a non-polar solvent or polar solvent, for 1 hr or 2 hr at 673K or 693K under nitrogen, in order to chemically upgrade the low-rank coal. A 1-methyl naphthalene (MN) was used as non-polar solvent and wash oil (WO) and Super-Solvent (SS) which is the more polar solvent used as polar solvent. In case of polar solvent as the treated solvent, the extraction yield at 1 hr at 673K reached 66.0 and 62.3 mass%, daf in WO and SS respectively, however, some of polar solvent remained in the extract because the polar solvent contained polar compounds of 8.5 and 21.7 mass% in WO and SS respectively. The extraction yield with MN at 673 K was 41.2 mass%, daf and it decreased with an increase in the severity of the extraction condition; it was 36.3 mass%, daf at 693K for 2 hr. However, the H/C and O/C ratios of the MN upgraded coal became the similar level as those of caking coals at 693K for 2 hr. Decarboxylation and aromatization reactions might occur during the solvent treatment.
