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关键物种的时间解析量化和低温四二氧化过程中的机理洞察

Maria Demireva¹, Kendrew Au¹, Nils Hansen¹

¹Combustion Research Facility, Sandia National Laboratories, Livermore, California 94551, USA. maria.p.demireva@gmail.com.

Physical chemistry chemical physics : PCCP

|March 19, 2024

概括

本研究量化了使用高压质谱法测量的四二氧化 (THF) 氧化中间体和产品. 这些发现揭示了当前氧化模型的局限性,特别是关于基性异构化率的局限性.

科学领域:

化学动力学化学动力学
燃烧化学燃烧化学是什么
大气化学大气化学

背景情况:

甲基 (THF) 是一种重要的工业溶剂,也是潜在的生物燃料成分.
了解THF氧化对于预测其在燃烧和大气环境中的行为至关重要.
现有的动力模型需要在与燃烧相关的高压条件下进行验证.

研究的目的:

在THF氧化过程中实验性地确定关键物种的时间解析度.
将实验结果与来自最先进的THF氧化机制的预测进行比较.
确定速度限制步骤并改进THF燃烧的动力建模.

主要方法:

高压多重光电化质谱 (MPIMS) 在7500 torr.
可调节真空紫外线 (VUV) 辐射用于物种电离.
全球碳平衡方法用于量化没有参考光电离体横截面的物种.

主要成果:

实验确定了ROO ̇, ̇OOQOOH,丁,氧化 (KHP) 和不和氧化 (UHP) 的度.
暂时确定甲作为UHP的分解产物.
现有的文献机制大大高估了THF消耗和KHP/UHP度.

结论:

目前的THF氧化机制由Fenard等人. 在高压条件下是不够的.
对于ROO ̇同质化到QOOH的速率系数是一个影响模型准确性的关键参数.
与环丹数据的比较表明,以太基显著影响反应性,需要准确的运动数据ROO ̇异构化和随后的反应.

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