A fast and efficient way for recovering organic carbon resources from a coal byproduct: separation and structural evaluation

Solvent extraction is an efficient and nondestructive approach to produce ash-free organic matters from direct coal liquefaction residue (DCLR). Isometric acetone/CS2 mixture (IACM) was adopted to extract DCLR to produce IACM-soluble fraction (IACM-SF) with a yield of 86.5%. The IACM-SF is of ash-free and high carbon content of 90.18%. The typical structural features of IACM-SF are substituted aromatic structures, nonsubstituted condensed and biphenyl aromatic structures, alkyl bridged linkages, hydrogenated aromatic structures, and heteroatom-containing structures. Therefore, the IACM-SF is a useful and valuable carbon resource that can be used for producing aromatics and preparation of carbon materials.