38. Selection Index of Low Rank Coals for Highly Efficienct Production of "HyperCoal"

Abstract

Ashless coal (HyperCoal) was produced through solvent extraction of coals at 360℃. This work was aiming at establishment of selection index of low rank coals for production of HyperCoal. Relationship between the amount of oxygen-containing functional groups in raw coals and the extraction yield was investigated. A good correlation between the amount of metal carboxylate groups and the extraction yield with an industrial polar solvent, crude methyl naphthalene oil (CMNO), was found and the correlation coefficient was 0.86. This result suggests that thermal extraction of low-rank coals strongly depends on the ionic cross-links rather than hydrogen bonds.