“碳达峰、碳中和”政策的实施将对煤的燃料利用带来较大限制。我国低阶煤储量丰富，将其直接作为能源利用不仅效率低，还会造成较大污染。低阶煤温和氧化解聚制备羧酸化学品，在拓展煤炭资源化利用途径的同时，还有望开发出羧酸化学品生产新工艺。根据低阶煤温和氧化解聚方法的差异，将其分为非催化氧化(化学试剂氧化和预处理氧化)、催化氧化和原位氧化，重点综述了这些氧化方法的特点。在非催化氧化中，化学试剂氧化法操作简单，但化学试剂消耗量大、氧化过程不易控制，且硝酸和次氯酸钠氧化剂易在产物中引入杂原子造成产物分离困难；预处理氧化可提高低阶煤利用效率并改善氧化产物分布，但处理过程相对繁琐；催化氧化法可加快反应速率、降低投入、减少能耗，催化剂的稳定性、选择性和高效性需进一步研究，催化剂回收也应更加关注；原位氧化反应操作灵活可控，有望调控低阶煤的氧化解聚过程。最后，阐述了当前低阶煤温和氧化解聚存在的问题以及未来发展方向。

 The implementation of "carbon peak and carbon neutral" policies will greatly limit the fuel-use of coals.  The low-rank coal is abundant in China, and it is not only inefficient to use it directly as energy, but also causes greater pollution. It is expected to develop a new process for production of carboxylic acid chemicals as well as expand the utilization of coal resources through the preparation of carboxylic acid chemicals by mild oxidative depolymerization of low rank coal. According to the difference of the methods, mild oxidative depolymerization of low-rank coals can be classified into non-catalytic oxidation (including chemical reagent oxidation and pretreatment oxidation), catalytic oxidation and in-situ oxidation. The development and characteristics of different oxidation methods for producing carboxylic acid chemicals from low-rank coals were mainly summarized. In non-catalytic oxidation, chemical reagent oxidation is easy to be carried out. Whereas it will cost a large consumption of chemical agents and the oxidation process is not easy to be controlled. At the same time, heteroatoms will be introduced into the resulting products for some oxidizing reagents such as nitric acid and sodium hypochlorite resulting in increasing difficulties of product separation. Pretreatment oxidation can improve the yield of products and utilization rate of low-rank coals, while the pretreatment process is relatively complicated. Catalytic oxidation method can speed up the reaction rate, and reduce investment and energy consumption. The stability, selectivity and efficiency of the catalyst need to be further studied, and the catalyst recovery should also be paid more attention. In-situ oxidation is flexible and controllable, which is expected to regulate the oxygen depolymerization process of low-rank coals. In the end, the current problems and future development direction of mild oxidative depolymerization of low-rank coals were discussed.

0 引言

1 非催化氧化

   1.1 化学试剂氧化

   1.2 预处理氧化

2 催化氧化

   2.1 钌离子催化氧化

   2.2 催化氧气氧化法

   2.3 Fenton试剂氧化

3 原位氧化

   3.1 过氧乙酸氧化

   3.2 电化学氧化

4 低阶煤氧化解聚现存问题与研究方向

5 结语