Atmospheric Chemistry

Photochemical smog, characterized by the formation of atmospheric oxidants, results from the oxidation of volatile organic carbon (VOC) in the presence of the oxides of nitrogen (NOx) and sunlight. Our group is primarily interested in the photochemical transformations of organic compounds in the lower atmosphere during smog production. Of particular interest is incorporation of oxides of nitrogen into secondary organic photoproducts such as peroxyacetyl nitrate (PAN) and alkyl nitrates. We attempt to understand the reactivity of individual organic compounds, the pathways of reactions, and the impact of these compounds on the regional and global atmosphere.

We accomplish our goals through a variety of methods, all of which are subjects of current projects:

1. deployment of instrumentation for measurement of ambient air
2. laboratory studies of specific reactions and products
3. interpretation of data from collaborative measurement experiments

We have been involved in collaborative projects like the Southern Oxidants Study (SOS), the North Atlantic Regional Experiment (NARE), Program for Research on Oxidants: PHotochemistry, Emissions, and Transport (PROPHET), Community Atmosphere-Biosphere Interactions Experiments (CABINEX) and the New England Air Quality Study (NEAQS).

One focus relates to the contribution of naturally-occurring organic compounds, such as isoprene, relative to human pollution from sources such as automobile exhaust. We are involved in the effort to elucidate the photochemical mechanism of isoprene oxidation by looking at the range of organic products both in ambient air an in smog chamber experiments.

Biosphere-Atmosphere Interactions
Recently we have been geting more involved in the emerging field of biosphere -atmosphere interactions. The focus of this attention is on a new doctoral training program known as Biosphere Atmosphere Research and Training (BART). See the BART website for more information. Our major interest is to understand the various processes that transform nitrogen in the atmosphere and the importance of atmospheric nitrogen input to forest ecosystems.

Biodiesel/Alternative Fuels
The age of cheap petroleum is coming to a close.  The sheer magnitude of the world’s energy consumption demands that the search for sustainable renewable alternatives be one of our country’s top strategic priorities.  Renewable biomass lately has been receiving increasing attention, although the use of biomass is not a new idea and many technologies have been developed to produce and distribute fuels such as ethanol.  Biodiesel is a renewable fuel made via a relatively simple process from animal or vegetable oil, which can be used interchangeably in all diesel or fuel oil applications. Biodiesel, a fuel known since the 1930s and in commercial production on all developed continents, is a particularly attractive option for transportable liquid fuel based on a multitude of benefits ranging from safety to energy density to environmental impact.  In the US, biodiesel is a large growth industry that still suffers from lack of supply, distribution and understanding.

We feel that renewable biomass fuels hold some of the most viable prospects for continued vehicle operation in the short term (next 50 years) until other alternative technologies mature.  We are involved in two efforts to bring biodiesel to the local market and to demonstrate the important role of biomass fuels. The Kalamazoo Biodiesel Co-op is a student-run small-scale production operation that allows people to learn how to make their own biodiesel from recycled vegetable oil. A research operation, called BroncoBiofuels, is focused on enhancing urban sustainability by developing market-driven ways to recover waste streams, such as recycled fats from a variety of sources, and bring the energy stored in these "wastes" back into the market.