A detailed chemical kinetic model has been developed for supercritical water oxidation (SCWO) of methylamine, CH₃NH₂, providing insight into the intermediates and final products formed in this process as well as the dominant reaction pathways. The model was adapted from previous mechanisms, with a revision of the peroxyl radical chemistry to include imine formation, which has recently been identified as the dominant gas‐phase pathway in amine oxidation. The developed model can reproduce previous experimental data on methylamine consumption and major product formation to reasonable accuracy, although with deficiencies in describing the induction time. Our simulations indicate that oxidation of the ^•CH₂NH₂ radical to methanimine, CH₂NH, is the major channel in methylamine SCWO, with subsequent hydrolysis of CH₂NH providing the experimentally observed reaction products ammonia and formaldehyde. Integral‐averaged reaction rates were used to identify major reaction pathways, and a first‐order sensitivity analysis indicated that the concentration of CH₃NH₂ is most sensitive to OH radical kinetics. Overall, this work clarifies the importance of imine chemistry in the oxidation of nitrogen‐containing compounds and indicates that they are necessary to model these compounds in SCWO processes.

中文翻译：

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亚甲胺超临界水氧化的详细化学动力学模型：亚胺形成的重要性

已经开发了用于甲胺CH ₃ NH _2的超临界水氧化（SCWO）的详细化学动力学模型，从而可以深入了解在此过程中形成的中间体和最终产物以及主要的反应途径。该模型改编自先前的机制，对过氧自由基化学进行了修改，以包括亚胺的形成，最近已确定亚胺的形成是胺氧化的主要气相途径。尽管在描述诱导时间方面存在缺陷，但是开发的模型可以以合理的精度重现有关甲胺消耗和主要产物形成的先前实验数据。我们的模拟表明^• CH ₂ NH _2的氧化自由基对甲亚胺，CH ₂ NH，是在甲胺SCWO的主要信道，用CH随后水解₂ NH提供实验观察到的反应产物氨和甲醛。积分平均反应速率用于确定主要的反应途径，一阶敏感性分析表明，CH ₃ NH ₂的浓度对OH自由基动力学最敏感。总的来说，这项工作阐明了亚胺化学在含氮化合物氧化中的重要性，并表明它们对于在SCWO工艺中对这些化合物进行建模是必要的。