In this paper, the physicochemical structure of hot melt products was characterized by industrial analysis, elemental analysis, infrared spectroscopy, coal and rock composition, Raman, and other means. Compared with raw coal, the ash content of thermally extracted coalsThermally extracted coals is significantly reduced, and the ash content in some thermally extracted coalsThermally extracted coals is negligible. The volatile content of thermally extracted coalsThermally extracted coals increased, and the small molecular weight substances increased. Reduction in fixed carbonCarbon content. The content of C element in thermally extracted is higher than that in raw coal, especially for low-rank coalLow-rank coal ZY and UT. The H/C ratio of XY, WY, and UT was greater than that of the raw coal, while the O/C of XY, ZY, and UT was reduced. The variation patterns of vitrinite reflectance differVitrinite reflectance differ among thermally dissolved coals derived from different coal types. Specifically, the vitrinite reflectance of thermally dissolved coals prepared from bituminous coals (XY and WY) decreases, while that of thermally dissolved coals obtained from low-rank coalsLow-rank coal (ZY and UT) increases to a certain extent. In terms of petrographic composition, all four thermally dissolved coals only contain vitrinite as their maceral component. During the heating process, some vitrinite undergoes slight pyrolysis, forming microparticulate structures. These structures appear gray-white or brown under an optical microscope. The Caking Index valuesCaking Index values of XY-TDC, WY-TDC, ZY-TDC, and UT-TDC (the four thermally dissolved coals) are 98, 97, 95, and 89, respectively—showing a remarkable improvement compared to their corresponding raw coals.