The gas phase atmospheric photolysis and reactions of key alkyl nitrates and their role in NOy partitioning.

Lead Research Organisation: University of Manchester
Department Name: Earth Atmospheric and Env Sciences


Alkyl nitrates play a crucial role in controlling the budgets of secondary organic aerosols, ozone, NOx, NOy and HOx throughout the troposphere and the importance of these families in determining atmospheric composition, the earth's radiative balance and any future change in climate can not be overemphasised. A number of recent regional and global model studies have demonstrated that vital kinetic and photolytic parameters, especially for the alkyl nitrates formed from the oxidation of biogenic volatile organic compounds, are missing, preventing atmospheric chemical models from describing oxidant chemistry well and hence determining lifetimes of key greenhouse gases and surface pollutants. These kinetic and photolytic parameters include their loss rate via photolysis, loss rate via reaction with OH and O3 and whether NOx is released on reaction with OH and O3. In this study a combination of Turbulent-Flow Chemical Ionisation Mass Spectrometry coupled with a Gas chromatography- electron capture detector (GC-ECD) for the detection of alkyl nitrates will be used to characterise the kinetics of reaction with OH of key alkyl nitrates, whilst a relative rate technique coupled with GC-ECD and GC-MS will be used to characterise the kinetics of reaction of unsaturated organic nitrates with O3 and a state of the art flash photolysis cavity ring system will be used to measure the photolysis and quantum yield of organic nitrates. Such data will be incorporated into models describing the troposphere and compared with available measurements. The proposed work will be crucial to the understanding of the effects of biogenic volatile organic compounds on atmospheric pollution and climate change.
Description Room temperature rate coefficients were determined for the reaction between 3,4-dinitrooxy-1-butene and 1,4-dinitrooxy-2-butene with OH. Also It was possible to determine the room temperature relative rate coefficient for 3,4-dinitrooxy-1-butene, 3-nitrooxy,3-methyl,4-hydroxy-1-butene / 3-hydroxy,3-methyl,4-nitrooxy-1-butene (inseparable mixture) with ozone.
Exploitation Route used in pollution modelling
Sectors Environment

Description so far the rate coefficients have not been used in any atmospheric models.
First Year Of Impact 2014
Sector Environment
Impact Types Societal

Description Outreach talk school visit Stalybridge 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Schools
Results and Impact Gave talk on research to Copley High School to whole school
Year(s) Of Engagement Activity 2012