AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Modeling Indoor Surface Chemistry Using Kinetic Multilayer Models
Pascale Lakey, Glenn Morrison, James Mattila, Youngbo Won, Krista Parry, Michael von Domaros, Douglas Tobias, Donghyun Rim, Jonathan Abbatt, Delphine K. Farmer, MANABU SHIRAIWA, University of California, Irvine
Abstract Number: 542 Working Group: The Air We Breathe: Indoor Aerosol Sources and Chemistry
Abstract Kinetic multilayer models were used to gain a better understanding of two different important indoor chemical systems; (1) the reactions of ozone with clothing and the formation of squalene ozonolysis products, (2) chemical processes in an indoor boundary layer and indoor surfaces. Both models treat chemical reactions and diffusion as well as adsorption and desorption to a surface.
The clothing model was able to reproduce measurements of carbonyls formed when ozone reacted with soiled clothing. Several parameters were constrained by molecular dynamic simulations. We demonstrated that clothing protects underlying skin from ozone and that soiled clothing can lead to carbonyl concentrations increasing to ppb levels depending on air exchange rates. Model outputs were inputted into a computational fluid dynamic model to estimate the distribution of ozone and squalene ozonolysis products throughout a room.
An indoor boundary layer model was developed to better understand the concentration gradient of OH radicals near indoor surfaces. It was shown that by including the chemistry of ozone with terpenes in the boundary layer, the OH uptake rate to surfaces was larger than would be predicted by traditional models. Factors which affected the OH uptake rate included the O3 uptake coefficient and the degree of turbulence within the room. In addition, we simulated the formation and loss of species in the gas phase upon floor-bleaching as measured during the HomeChem campaign. The model included a boundary layer next to the bleach and reactions occurred in the aqueous bleach, in the gas phase and on particle and room surfaces. The model was able to reproduce the loss of ammonia and the formation of chloramines.