低阶煤的热溶萃取提质是利用溶剂在温和条件下对低阶煤进行热萃取，通过对原煤的脱水与多级分离，可得到无水、无灰、高热值与良好热塑性的萃取产物与低水分的萃余煤。同时萃取产物在配煤炼焦、高级燃料及炭材料制备等多个领域均具有实际应用优势，拥有较高的附加值，并且该技术中溶剂具备可循环利用的优势。因此，热萃取提质是实现低阶煤分级分质转化利用的有效途径之一。本综述首先介绍了现有各类低阶煤提质处理方式；然后梳理了热溶萃取提质发展脉络，重点综述了低阶煤热溶萃取提质的各类影响因素、反应机理、现有工艺以及产物的利用途径；最后利用“Web of Science核心合集”作为数据源，使用CiteSpace科学计量软件刻画了煤溶剂萃取的知识图谱，通过对研究主题进行分析，总结研究方向并预测研究热点，为低阶煤热溶萃取提质研究提供一定的参考价值。综合分析表明：新型低成本绿色溶剂的选取、萃取产物结构表征及高值利用等领域具有较高的研究趋势，同时需要对萃取机理及萃取物特性定向调控开展深入研究，进一步推动工艺规模化生产进程。

The degradative solvent extraction of low rank coal is the use of solvents to extract low rank coal under mild conditions, through the dehydration and multi-stage separation of the raw coal: the extraction products with no water content, no ash content, high calorific value properties and excellent thermoplastic properties, and low moisture of the extractive residual coal can be obtained. At the same time, the products have practical application advantages in many fields such as coal coking, advanced fuel and carbon material preparation, which have high added value, and the solvent in this technology has the advantage of being recyclable. Therefore, degradative solvent extraction is one of the effective ways to realize the graded fractionated conversion and utilization of low-rank coal. This review firstly introduces the existing low rank coal upgrading methods, and then reviews the development of degradative solvent extraction, focusing on the various influencing factors, reaction mechanisms, existing processes and product utilization of low rank coal upgrading by degradative solvent extraction. Finally, using the "Web of Science core collection" as the data source, the knowledge graph of coal solvent extraction was carved using CiteSpace scientometric software, and the research themes were analyzed to summarize the research directions and predict the research hotspots, providing some reference value for the research of degradative solution extraction of low-rank coal. The comprehensive analysis shows that: the selection of new low-cost green solvents, structural characterization and high-value utilization of extraction products have high research trends, while in-depth research on extraction mechanism and targeted regulation of extractant properties is needed to further promote the process of large-scale production.