Much of atmospheric chemistry has focused on polluted, urban environments, but it is emerging that there is important unknown chemistry occuring in the unpolluted atmosphere. This shortfall prohibits us from fully understanding, for instance, the lifetime of greenhouse gases like methane. We are investigating the new chemical processes needed to describe the fate of organic compounds in the unpolluted atmosphere.

Organic compounds containing nitrogen, including amines, are distributed throughout the atmosphere, where they are removed through oxidation reactions. Surprisingly little attention, however, has been directed towards the oxidation chemistry of amines. This problem is of growing importance as the leading technology for carbon capture from power stations involves amine solvents, which would potentially lead to large new sources of amines to the atmosphere. In this project we are developing the new chemistry required to describe the oxidation of amines in the atmosphere, allowing us to better predict the impact of these under-studied molecules on air quality.

Aromatic hydrocarbons are present at high levels in liquid transportation fuels. This is particularly true for gasoline, where the elimination of alkyl lead octane boosters has made substituted aromatics such as toluene essentially required because of their high octane ratings. Despite their importance there is still much that we do not know about the combustion chemistry of aromatic hydrocarbons. We are investigating these processes using both theoretical kinetics and synchrotron-based experimental techniques.

The formation of polycyclic aromatic hydrocarbons (PAHs) in flames is a key step in the generation of soot particles, major combustion pollutants that are detrimental to public health as well as being implicated in climate change.  Similar chemistry is also proposed to take place in planetary atmospheres and in the interstellar medium.  Even the initial stages in the chemistry of PAH formation are not well understood. This project is focused on developing an improved description of the PAH formation in flames, particularly the destruction and growth of the first aromatic ring(s).