Hydrogen transferring liquefaction of highly inert-containing bituminous coals using tetrahydrofluoranthene.

Hydrogen transferring liquefaction of highly inert-containing bituminous coals was studied under high temperature-short contact time conditions using tetrahydrofluoranthene as a donor solvent to reveal the efficiency of such a coal liquefaction procedure against the coals and reactivities of inert macerals. The liquefaction of the present study was very effective to give the sum yields of oil and asphaltene larger than 60% against all coals. When ground coals passing 60 mesh screen, the deashing pretreatment was effective to decrease the yields of THE insolubles and increase oil, the extent depending very much on the coals. However, its effects were negligible against coals passing 200 mesh. Based on the THFI yields compared to the maceral compositions of the coals, whole semifusinite and parts of fusinite and micrinite macerals were found possible to be liquefied under the present conditions, especially when assisted by the deashing pretreatment.The effect of deashing was discussed in connection with the importance of fusibility as well as particle size of coals in the coal liquefaction, where the effective stabilization of fragment radicals derived from coal molecules through the hydrogenation or dissolution with the donor solvent is most requested. The removal of divalent cations which bridge the coal macromolecules through their oxygen functionalities may accelerate the fusibility.