Zhundong coal (ZDC) has attracted much attention due to its high alkali metal content which can lead to a series of problems such as furnace slagging and ash fouling. Supercritical water gasification (SCWG) become a better choice for ZDC coal utilization because of its unique chemical and physical properties. The transformation mechanism of alkali metals during SCWG process was different from conventional ways of coal utilization. Systematic research about it could hardly be found. In this study, ZDC was used to explore sodium transformation mechanism and kinetics during supercritical water gasification under typical conditions. We got four kinds of sodium including the water-soluble fraction (L1), the carboxylic matrix-associated fraction (L2), the macromolecular organic group-associated fraction (L3), and the inorganic silicate mineral fraction (L4) through sequential extraction method after SCWG. A reaction pathway of sodium transformation in supercritical water gasification was proposed. A quantitative kinetic model for describing sodium transformation mechanism was developed. Finally, it was found that, L1 played an important role in catalytic process and mineral in coal weaken the catalytic process by combining with L1. L2 and L3 served as the two important intermediate products in the coal gasification, which explained the catalytic mechanism of sodium. L3 showed better reactivity. Sodium finally tended to deposit in the form of NaSiAlO₄ (L4) which was stable and environmentally friendly. All of these could provide basis for high-efficiency utilization of ZDC and the design of a reactor.

准东煤（ZDC）由于其高碱金属含量而引起了广泛的关注，这会导致一系列问题，例如炉渣和灰烬结垢。超临界水气化（SCWG）由于其独特的化学和物理特性而成为ZDC煤炭利用的更好选择。SCWG过程中碱金属的转化机理与传统的煤炭利用方式不同。几乎找不到关于它的系统研究。在这项研究中，ZDC用于探索典型条件下超临界水气化过程中钠的转化机理和动力学。我们得到了四种钠，包括水溶性级分（L1），与羧酸基质相关的级分（L2），与大分子有机基团相关的级分（L3），SCWG后采用顺序萃取法提取无机硅酸盐矿物级分（L4）。提出了超临界水气化过程中钠转化的反应途径。建立了描述钠转化机理的定量动力学模型。最后，发现L1在催化过程中起着重要作用，而煤中的矿物通过与L1结合而削弱了催化过程。L2和L3是煤气化过程中的两个重要中间产物，这解释了钠的催化机理。L3显示出更好的反应性。钠最终倾向于以NaSiAlO的形式沉积 建立了描述钠转化机理的定量动力学模型。最后，发现L1在催化过程中起着重要作用，而煤中的矿物通过与L1结合而削弱了催化过程。L2和L3是煤气化过程中的两个重要中间产物，这解释了钠的催化机理。L3显示出更好的反应性。钠最终倾向于以NaSiAlO的形式沉积 建立了描述钠转化机理的定量动力学模型。最后，发现L1在催化过程中起着重要作用，而煤中的矿物通过与L1结合而削弱了催化过程。L2和L3是煤气化过程中的两个重要中间产物，这解释了钠的催化机理。L3显示出更好的反应性。钠最终倾向于以NaSiAlO的形式沉积₄（L4）稳定且环保。所有这些都可以为ZDC的高效利用和反应堆的设计提供基础。