Inhibiting and promoting effects of NO on dimethyl ether and dimethoxymethane oxidation in a plug-flow reactor
Inhibiting and promoting effects of NO on dimethyl ether and dimethoxymethane oxidation in a plug-flow reactor
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DOI：
10.1016/j.combustflame.2020.08.027
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发表时间：
2020-09
影响因子：
4.4
通讯作者：
Hao Zhang;Steffen Schmitt;L. Ruwe;K. Kohse-Höinghaus
中科院分区：
文献类型：
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作者：
Hao Zhang;Steffen Schmitt;L. Ruwe;K. Kohse-Höinghaus
在400-1000 K温度范围内，在近常压活塞流反应器中研究了NO（1000，2000 ppm）对二甲醚（DME）和二甲氧基甲烷（DMM）低温氧化反应的影响。使用原位电子电离分子束质谱仪（EI-MBMS）测量反应物、中间体和产物，特别注意以前很少检测到的含氮物质。探索性建模与公布的机制进行，表明进一步的模型开发的必要性。潜在的动力学燃料/NO相互作用的实验观察的基础上进行了讨论。结果表明，NO的加入对DME反应性的整体抑制作用在低温制度，但在较高的温度下，一个显着的促进作用。对于DMM，观察到类似的NO的温度依赖性效应，但仅针对高NO浓度（2000 ppm）。NO的加入显著抑制了DME和DMM烃类中间产物的生成，但显著促进了DME甲酸甲酯和甲醇的生成。几个含氮物种检测后，NO添加。NO + HO 2和NO + OH的相互作用以及NO的再生途径被认为对DME和DMM的氧化都有影响，而NO + RO 2（R，燃料自由基）反应的重要性取决于DME和DMM各自的RO 2自由基的反应性。这些结果有助于理解OMEn/NO相互作用，并作为进一步的模型开发的基础，通过提供新的和详细的DME/NO和DMM/NO氧化的形态数据。
The effects of NO addition (1000, 2000 ppm) on the low-temperature oxidation of dimethyl ether (DME) and dimethoxymethane (DMM), as particular cases of oxymethylene ethers (OMEn) withn= 0 and 1, have been investigated in a plug-flow reactor at near-atmospheric pressure in a temperature range of 400–1000 K. Anin-situelectron ionization molecular-beam mass spectrometer (EI-MBMS) was used to measure the reactants, intermediates, and products, with particular attention on nitrogenous species that were scarcely detected previously. Explorative modeling with published mechanisms was performed, indicating the necessity of further model development. Potential kinetic fuel/NO interactions are discussed based on the experimental observations. The results reveal an overall inhibiting effect of NO addition on DME reactivity in the low-temperature regime, but a pronounced promoting effect at higher temperatures. For DMM, a similar temperature-dependent effect of NO was observed, but only for high NO concentration (2000 ppm). NO addition significantly suppresses the formation of hydrocarbon intermediates for both DME and DMM, but remarkably promotes the formation of methyl formate and methanol for DME. Several nitrogenous species were detected upon NO addition. The interactions of NO + HO2and NO + OH, together with the regeneration routes of NO, are thought to be influential for both DME and DMM oxidation, while the significance of the NO + RO2(R, fuel radical) reaction depends on the reactivity of the respective RO2radical of DME and DMM. These results contribute to the understanding of OMEn/NO interactions and serve as a basis for further model development by providing new and detailed speciation data for DME/NO and DMM/NO oxidation.