Preparation of Activated Carbon With High-Specific Surface Area from Degradative Solvent Extraction Residue of Low-Rank Coal

The degradative solvent extraction is believed to be a promising technology for the efficient upgrading of low rank coal. However, there is rather few study focused on the effective utilization of the extraction residue. Therefore, the high-specific surface area activated carbons preparation by the extraction residue through physical activation and chemical activation were studied in this work. It was found some porous structure was formed in the extraction residue, because of the removal of low molecular weight fraction from the coal by the degradative solvent extraction. The CO2 gasificatin activation of the extraction residue was promoted, which benefit to the activation carbon preparation by physical activation. The specific surface area of the activated carbon obtained from the extraction residue by physical activation was as high as 1837 m2/g, much higher than that of the activated carbon from raw coal. Besides, the mesoporous proportion was also enhanced. The specific surface area of the activated carbon obtained from the extraction residue by chemical activation was up to 2216 m2/g. The same activated carbon from the raw coal was only 1660 m2/g. Thus, the possibility and advantage of activated carbon preparation by the extraction residue was confirmed. © 2022, Science Press. All right reserved.