Characterization on the ultraclean carbons extracted from direct coal liquefaction residue using petroleum ether

ABSTRACT

Direct coal liquefaction residue is a coal waste with high ash and sulfur content, but also rich in valuable organic carbons. In this work, the ultraclean carbons were obtained by solvent extraction using petroleum ether at a mild temperature. The petroleum ether extractable fraction is ash-free with high carbon content, but low nitrogen and sulfur. The petroleum ether extractable fraction is reasonable to be cleaned for fuel use or converted into carbon products. Detailed characterizations on the chemical composition and structural features of petroleum ether extractable fraction were performed to supply fundamental information for additional treatment.

KEYWORDS:

• direct coal liquefaction residue
• solvent extraction
• petroleum ether
• ultraclean carbons

Additional information

Funding

This work was subsidized by the Key Scientific Research Program Plan for Colleges and Universities of Henan Province [21B530007], National Natural Science Foundation of China [Grant 21606210, U1908226, 21706172, 51904274, and 51704263], Program for Innovative Research Team (in Science and Technology) in University of Henan Province [19IRTSTHN028], Open Project of Henan Engineering Laboratory of Coal-based Ecological Fine Chemical Engineering [D202004], and Henan Postdoctoral Foundation [2016-106].