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Regulation of radicals by hydrogen-donor solvent in direct coal liquefaction

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Abstract

Radicals are important intermediates in direct coal liquefaction. Certain radicals can cause the cleavage of chemical bonds. At high temperatures, radical fragments can be produced by the splitting of large organic molecules, which can break strong chemical bonds through the induction pyrolysis of radicals. The reaction between the formation and annihilation of coal radical fragments and the effect of hydrogen-donor solvents on the radical fragments are discussed in lignite hydrogenolysis. Using the hydroxyl and ether bonds as indicators, the effects of different radicals on the cleavage of chemical bond were investigated employing density functional theory calculations and lignite hydrogenolysis experiments. Results showed that the adjustment of the coal radical fragments could be made by the addition of hydrogen-donor solvents. Results showed that the transition from coal radical fragment to H radical leads to the variation of product distribution. The synergistic mechanism of hydrogen supply and hydrogenolysis of hydrogen-donor solvent was proposed.

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Acknowledgements

The authors are grateful to the National Natural Science Foundation of China (Grant No. 22038008) and the 2030 Major Project Pilot Project from CHN Energy, China (Grant No. GJNY2030XDXM-19-13,2) for the financial support.

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Authors and Affiliations

  1. State Key Laboratory of Clean and Efficient Coal Utilization, Taiyuan University of Technology, Taiyuan, 030024, China

    Wang Li, Wen-Ying Li, Xing-Bao Wang & Jie Feng

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  1. Wang Li
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Correspondence to Wen-Ying Li.

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Li, W., Li, WY., Wang, XB. et al. Regulation of radicals by hydrogen-donor solvent in direct coal liquefaction. Front. Chem. Sci. Eng. 16, 1689–1699 (2022). https://doi.org/10.1007/s11705-022-2186-7

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  • DOI: https://doi.org/10.1007/s11705-022-2186-7

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