Aerosol Volatilisation
Understanding the partitioning of molecular constituents between the gas and particle phases is central to the whole endeavour of aerosol science. This project applies ultra-sensitive techniques to investigate the volatilisation of low and semi-volatile components from aerosol particles, their response to humidity and temperature, and refining predictive tools crucial for understanding air quality.
Organic aerosols are an important class of aerosol to study due to their effect on climate, weather systems, human health and global ecosystems. Despite their importance, they remain poorly understood due to their molecular complexity, reactivity and large diversity in properties. The lack of accurate vapour pressure (VP)data of organic species – including natural atmospheric, intentionally released and anthropogenic more broadly – accompanied by the large uncertainty in the estimation of their VPs has been presented as the focus for improvement in this proposal.
The retrieval of particle volatility from single particles employs measurements using electro-dynamic balances and aerosol optical tweezers to experimentally determine the vapour pressures of important organic species has been proposed, along with the use of this data in improving current vapour pressure estimation methods for organic compounds. The subsequent coupling of an improved VP estimation model into an aerosol box model, “PyBox”, with the consideration of kinetic effects such as viscosity and reactions upon drying will be developed.
Relevant Publications
[1] Petters, S. S.; Hilditch, T. G.; Tomaz, S.; Miles, R. E. H.; Reid, J. P.; Turpin, B. J. Volatility Change during Droplet Evaporation of Pyruvic Acid. ACS Earth Sp. Chem. 2020, 4 (5), 741–749. pdf
[2] Tikkanen, O.-P.; Hämäläinen, V.; Rovelli, G.; Lipponen, A.; Shiraiwa, M.; Reid, J. P.; Lehtinen, K. E. J.; Yli-Juuti, T. Optimization of Process Models for Determining Volatility Distribution and Viscosity of Organic Aerosols from Isothermal Particle Evaporation Data. Atmos. Chem. Phys. 2019, 19, 9333–9350. pdf
[3] Pereira, K. L.; Rovelli, G.; Song, Y. C.; Mayhew, A. W.; Reid, J. P.; Hamilton, J. F. A New Aerosol Flow Reactor to Study Secondary Organic Aerosol. Atmos. Meas. Tech. 2019, 12 (8), 4519–4541. pdf
[4] Ingram, S.; Rovelli, G.; Song, Y.-C.; Topping, D.; Dutcher, C. S.; Liu, S.; Nandy, L.; Shiraiwa, M.; Reid, J. P. Accurate Prediction of Organic Aerosol Evaporation Using Kinetic Multilayer Modeling and the Stokes–Einstein Equation. J. Phys. Chem. A 2021, 125, 3444–3456. pdf
[5] Krieger, U. K.; Siegrist, F.; Marcolli, C.; Emanuelsson, E. U.; Gøbel, F. M.; Bilde, M.; Marsh, A.; Reid, J. P.; Huisman, A. J.; Riipinen, I.; Hyttinen, N.; Myllys, N.; Kurtén, T.; Bannan, T.; Percival, C. J.; Topping, D. A Reference Data Set for Validating Vapor Pressure Measurement Techniques: Homologous Series of Polyethylene Glycols. Atmos. Meas. Tech. 2018, 11 (1), 49–63. pdf
BARC Researchers
Prof. Jonathan Reid, Thomas Hilditch
BARC Collaborators
Prof. David Topping (University of Manchester), Dr. Ulrich Krieger (ETH-Zuirch)
Funding
EPSRC Centre for Doctoral Training in Aerosol Science and DSTL