COLLABORATIVE RESEARCH: Chlorine Activation in Biomass Burning Plumes

该项目是一项合作努力，旨在调查生物质燃烧产生的氯颗粒排放以及这些排放对大气臭氧和小颗粒形成的影响。这项工作结合了卡内基梅隆大学（CMU）和华盛顿大学（UW）大气化学家的设备和专业知识，目的是在CMU燃烧设施的大型烟雾室反应堆中进行一套详细的实验室实验。室内将充满全球相关的氯化物排放生物质燃料(如各种类型的草（如锯草、线草、稻草）和棕榈（小型棕榈物种）的公开燃烧产生的烟雾。气相反应物和产物浓度的变化将使用华盛顿大学最先进的化学测量仪器实时确定。研究人员将应用动力学盒模型来推导参数的组合，这些参数可以为区域和全球模型中使用的参数的开发提供最佳的测量模型协议。微粒氯与氮氧化物气体发生有效反应，在气相中释放出硝基氯（ClNO2）。ClNO2的存在可以显著扰乱对流层的氧化剂收支、氯（ClOx）、氢（HOx）和氮氧化物自由基的循环、有机化合物的氧化和相关的有机气溶胶形成以及地面臭氧水平。该项目将是第一个研究五氧化二氮（N2O5）与氯化物在代表生物质燃烧气溶胶的颗粒系统中反应形成和产生ClNO2的实验室研究。

This project is a collaborative effort to investigate the emissions of particulate chloride from biomass burning and the implications of these emissions on the formation of atmospheric ozone and small particles. The effort combines the facilities and expertise of atmospheric chemists at Carnegie-Mellon University (CMU) and University of Washington (UW) for the purpose of conducting a detailed set of laboratory experiments in a large smog chamber reactor in CMU's combustion facility. The chamber will be filled with smoke from the open combustion of globally relevant chloride emitting biomass fuels such as various types of grasses (e.g. Sawgrass, Wiregrass, Rice straw), and Palmetto (small palm species). Changes in the concentrations of gas-phase reactants and products will be determined in real-time using UW's state-of-the-art chemical measurement instrumentation. The investigators will apply kinetic box models to derive the combination of parameters that give the best measurement-model agreement for the development of parameters that can be used in regional and global models.Particulate chloride undergoes efficient reactions with nitrogen oxide gases, releasing nitryl chloride (ClNO2) in the gas phase. The presence of ClNO2 can significantly perturb the troposphere's oxidant budget, the cycling of chlorine (ClOx), hydrogen (HOx), and NOx radicals, the oxidation of organic compounds and associated organic aerosol formation, and ground-level ozone levels. This project will be the first laboratory study to investigate the formation and yield of ClNO2 from dinitrogen pentoxide (N2O5), reacting with chloride in particle systems representative of biomass burning aerosols.