Introduction Solvent extraction of coal is a process to separate only organic components from coal. In this process, an organic solvent and coal are mixed and heated to dissolve the organic components of coal and the extracted solution is separated from the residual solid. Ash-free coal (AFC) is obtained by separating the solvent from this extracted solution. The characteristics of AFC manufactured through a solvent extraction process vary with changes in applied conditions such as solvent types, extraction temperatures, and recovering methods [1,2]. The present study was intended to examine changes in the characteristics of AFC according to changes in recovering methods which are the final stage of the AFC manufacturing process. To this end, we produced the solvent-extracted solution in which the organic components of coal were dissolved, separated out AFC from the liquid solution by vacuum distillation (VD) and dilution precipitation (DP), and compared the SEM, BET, FTIR and ~(13)C NMR results of the AFC samples.
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