RUI: Far Ultra-Violet (172 nm) Photolysis of Gaseous Anthropogenic Pollutants

该奖项来自化学系的环境化学科学项目。 加州州立大学的Mads P. Sulbaek Andersen教授和他的小组研究了远紫外线（FUV）对空气中污染物的光解作用。挥发性有机污染物是从家庭和工业过程中排放出来的，在地方到全球范围内影响人类和环境健康。该项目研究气相高级氧化工艺（AOPs）背后的化学，该工艺可以直接在工厂排放点或建筑空调系统中帮助净化空气。AOP的承诺是，该技术可以限制与传统的基于过滤器的空气净化系统相关的高能耗。然而，在高级氧化工艺中使用的FUV光解和工艺可能会产生比母体污染物更具毒性的化合物。准确理解与FUV降解有机污染物相关的基本动力学和化学反应途径对于确定所产生化合物的性质及其环境归宿和影响至关重要。这项研究的结果影响了我们在分子水平上对影响城市空气质量的光化学过程的理解。该项目为本科生提供培训机会，并在一个主要为本科生服务的少数民族机构中支持丰富的研究学习环境。对于挥发性有机化合物，在FUV波长（~121-200 nm）下引发的光解量子产率和化学氧化机制并不为人所知。该项目使用了一个温度控制的先进的光化学模拟室与原位准分子辐射灯和多程分析光学。反应物和氧化产物的监测使用光学技术，包括傅里叶变换红外光谱和高分辨率真空紫外分光光度法。紫外吸收截面是从120-200 nm处测量的，作为温度的函数，用于工业过程中排放的重要的高容量化合物（芳烃、羰基化合物、含氮化合物）。的172 nm的量子产率的光解测量和光解机制进行了研究作为压力，温度和O2分压的函数。本研究提供了新的知识，基础光化学和用于定量评估的命运和影响的有机气体污染物的FUV光化学过程中形成的产品。该研究团队主要由该少数民族服务机构的本科研究人员组成。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This award is from the Environmental Chemical Sciences Program in the Division of Chemistry. Professor Mads P. Sulbaek Andersen of California State University, Northridge and his group investigate Far Ultra-Violet (FUV) photolysis of airborne pollutants. Volatile organic pollutants are emitted from domestic and industrial processes and impact the human and environmental health on local to global scales. This project investigates the chemistry behind gas-phase Advanced Oxidation Processes (AOPs), which can assist in purification of air directly in factory emission points or in building air-conditioning systems. The promise of AOP is that the technology can limit the high energy consumption associated with traditional filter-based air-cleaning systems. However, the FUV photolysis and processes utilized in AOPs may result in compounds more toxic than the parent pollutant. An accurate understanding of the fundamental kinetics and chemical reaction pathways associated with FUV degradation of the organic pollutants is crucial to determining the nature of the resulting compounds and their environmental fate and impact. The results of this research impact our understanding at a molecular level of photochemical processes that impact urban air quality. The project provides training opportunities for undergraduate students and supports a research-rich learning environment at a primarily undergraduate, minority-serving, institution. Photolysis quantum yields and chemical oxidation mechanisms initiated at FUV wavelengths (~121-200 nm) are not well known for volatile organic compounds. This project uses a temperature-controlled advanced photochemical simulation chamber with in-situ excimer-radiation lamps and multi-pass analytical optics. Reactants and oxidation products are monitored using optical techniques including Fourier transform infra-red spectroscopy and high-resolution vacuum UV spectrophotometry. UV absorption cross sections are measured from 120-200 nm, as a function of temperature, for important, high-volume compounds emitted from industrial processes (aromatics, carbonyls, N-containing compounds). The 172-nm quantum yields of photolysis are measured and the photolysis mechanisms are investigated as a function of pressure, temperature and O2 partial pressure. This research provides new knowledge on fundamental photochemistry and is used for quantitative assessment of the fates and impact of the products formed during FUV photochemistry of organic gaseous pollutants. The research team is largely comprised of undergraduate researchers at this minority serving institution.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.