Chemical Ionization Time-of-Flight Mass Spectrometer for Particle and Gas-Phase Organic Speciation

Aerosol particles have important impacts on visibility, acid deposition, climate, and human health, although large uncertainties remain in quantifying their chemical composition and atmospheric transformations. A large fraction of the anthropogenic aerosol is generated from energy-related activities, and organic compounds are known to constitute a significant fraction of ambient aerosol mass. Organic aerosol can be directly emitted from combustion sources or formed through gas-phase reactions of volatile organic compounds. This Small Business Innovation Research Phase I project addresses the need for improved monitoring technologies for continuous particulate mass and chemical speciation of ambient aerosols. A prototype Aerosol Chemical Speciation Monitor will be developed that measures ambient aerosol mass and chemical composition of non-refractory PM2.5 aerosol particles in real-time, providing quantitative measurements of particulate ammonium, nitrate, sulfate, chloride, and organics. The instrument will be designed to run autonomously for extended periods of time and will need no expensive post-processing analysis. The Aerosol Chemical Speciation Monitor will be a simple, robust, modestly-priced, aerosol chemical speciation instrument ideal for routine monitoring of local and regional air quality, for continuous emissions monitoring, and for process control monitoring. The Phase I project succesfully demonstrated the feasibility of the Aerosol Chemical Speciation Monitor. A prototype was constructed and deployed in a field campaign for intercomparison with routine environmental monitoring instruments. Progress was made addressing quantification issues. During Phase II, a commercial version of the instrument will be developed. Specific tasks include designing and constructing new hardware, optimizing the design of the inlet and detector, and developing new data anlysis tools for fast and broad dissemination of particulate mass loadings and chemical composition. Commercial Applications and Other Benefits: The Aerosol Chemical Speciation Monitor will provide cost-effective, quantitative particulate matter mass loading and chemical composition data for determining compliance with air quality standards, and for inclusion in atmospheric climate models. The primary market for this instrument will be government agencies that conduct routine environmental monitoring programs. In addition, atmospheric research groups at universities and national laboratories will provide a substantial market. We expect that the system developed in this program will yield a significant level of direct commercial sales in the atmospheric science and environmental pollution research and development communities.