Abstract
With the transformation of energy structure to low carbon, the clean and efficient utilization of coal has received extensive attention. Among them, the technology of preparing super-clean coal by solvothermal extraction has become a research hotspot because of its good product characteristics. In this paper, FGZ coal was used as a raw material to explore its synergistic extraction effect with wood charcoal at different mass ratios, and the extracted products were systematically characterized by various analytical methods. The results show that the addition of biomass can effectively improve the extraction yield of this coal. When the biomass addition ratio was 35%, the extraction yield reached the highest value of 69.47%, which was about 28.3% higher than that without biomass. Hypercoal has a smooth surface with significantly fewer impurities than raw coal. At the same time, Raman spectroscopy and X-ray diffraction analysis showed that when the biomass addition ratio was 35%, the ID/IG reached a minimum value of 0.8354, and the structural order of the extracted product was the highest. When the biomass addition ratio was 35%, the Lc reached a maximum value of 2.0569 nm, indicating the highest degree of carbon layer stacking and structural order among the samples.