Zhi Zheng , Jun Shen , Zhenqing Han , Yu Chen , Yifan Bai
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引用次数: 0
Abstract
Ammonia-coal combustion mitigates CO2 emissions, yet nitrogen oxide emissions and char nitrogen oxidation mechanisms require further study. Our research employs density functional theory to explore coal char interactions with NO, NH3, and the impact of hydroxyls (–OH) and oxygen on reduction–oxidation processes. Findings indicate oxygen aids in forming hydroxyls on coal char, facilitating NO to NO2 conversion, lowering the activation energy for ammonia-coal oxidation to NO2. Oxygen also promotes char nitrogen oxidation to NO, reducing its activation energy. In NH3/coal/O2 systems, NH3 oxidation initiates NO formation. With the increase of the temperature, the reduction rate of NO by ammonia is always higher than the production rate of NO.
氨化煤燃烧可减少二氧化碳排放，但氮氧化物排放和煤炭氮氧化物机制还需要进一步研究。我们的研究采用密度泛函理论探索煤炭与 NO、NH3 的相互作用，以及羟基（-OH）和氧气对还原-氧化过程的影响。研究结果表明，氧气有助于在煤炭上形成羟基，促进 NO 向 NO2 的转化，降低氨-煤氧化成 NO2 的活化能。氧气还能促进煤炭氮氧化成 NO，降低其活化能。在 NH3/ 煤/O2 系统中，NH3 氧化会启动 NO 的形成。随着温度的升高，氨还原 NO 的速率总是高于 NO 的生成速率。
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Computational and Theoretical Chemistry publishes high quality, original reports of significance in computational and theoretical chemistry including those that deal with problems of structure, properties, energetics, weak interactions, reaction mechanisms, catalysis, and reaction rates involving atoms, molecules, clusters, surfaces, and bulk matter.
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