The effects of sulfur on fuel nitrogen conversion in combustion

CBET-0756144马歇尔燃烧是能源的主要来源，但燃料中的硫和氮可能成为与烟雾有关的污染物。拟议的研究计划将确定硫，通常是液体和固体燃料中的微量成分，如何影响燃料燃烧时氮氧化物的形成。这些氮氧化物是重要的污染物，但导致其形成的化学细节尚未完全了解。 这种限制对于涉及含硫化合物的催化循环尤其如此，其反应性已在实验室中得到证实。将采用光化学反应器来表征短寿命物种的反应。测量将从室温到高温条件下，通过可见光和紫外光谱，产生的反应物和/或产品的浓度曲线作为时间的函数在微秒的时间尺度。反应性数据将在分子水平上根据化学键转换时的能量变化进行解释。这一理论解释将有助于可靠地外推到新的条件下，从这个程序的结果将被用来构建一个定量的数值模型之间的相互作用的硫和氮的化合物在火焰中。 然后，这些信息可用于帮助设计条件和技术，从而降低燃烧室的氮氧化物排放。最终目标是通过减少低层大气臭氧、光化学烟雾和酸雨来改善空气质量。拟议工作的更广泛影响是通过在技术和科学界发表出版物和介绍以及培训和教育新的科学家产生的。

CBET-0756144MarshallCombustion is the major source of energy, but sulfur and nitrogen in fuels can become pollutants related to smog. The proposed research program will define how sulfur, normally a trace component in liquid and solid fuels, influences the formation of nitrogen oxides when the fuel is burned. These nitrogen oxides are of concern as significant pollutants, but the details of the chemistry leading to their formation are incompletely understood. This limitation is especially true of catalytic cycles involving sulfur-containing compounds, whose reactivity has been demonstrated in the laboratory. Photochemical reactors will be employed to characterize reactions of short-lived species. Measurements will be made from room-temperature to high-temperature conditions by means of visible light and ultraviolet spectroscopy, yielding concentration profiles of reactants and/or products as a function of time on a microsecond time scale. The reactivity data will be interpreted at the molecular level in terms of energy changes as chemical bonds are transformed. This theoretical interpretation will aid reliable extrapolation to new conditions.Results from this program will be used to construct a quantitative numerical model for interactions between sulfur and nitrogen compounds in flames. Such information can then be used to assist the design of conditions and technologies which lead to lower emissions of nitrogen oxides from combustors. The ultimate goal is to improve air quality through reduction of low-level atmospheric ozone, photochemical smog and acid rain. Broader impacts of the proposed work arise through publications and presentations in the technical and scientific community and by the training and education of new scientists.