Secondary Organic Aerosol Formation from Tire Emissions in an Oxidation Flow Reactor

MINGHAO HAN, Don Collins, University of California, Riverside

     Abstract Number: 417
     Working Group: Urban Aerosols

Abstract
Partly as a consequence of the significant reductions in vehicular exhaust emissions over the past few decades, non-exhaust emissions, such as those from brake and tire wear, are now recognized as an increasingly significant source of traffic-related particulate pollution. Previous tire wear research has predominantly focused on the emissions of primary aerosol particles, while the study of gaseous organic compounds emitted directly from tires remains substantially underdeveloped. The composition of these gaseous emissions can be complex due to the variety of additives used in tire production to meet different performance standards, leading to variability in emissions based on different manufacturing and processing techniques. Moreover, the detailed mechanisms through which these chemical compounds transform in the atmosphere, and the environmental fate of these emissions are not well-understood. Our study specifically examines the potential SOA formation from tire emissions using an oxidation flow reactor (OFR). We conducted experiments employing a custom-built enclosure in which whole tires were heated to temperatures expected while in use. Tires of various brands, types, and ages were tested to evaluate the SOA formation potential of emitted precursors. Findings from the study enhance our understanding of the complex processes by which tire emissions contribute to urban air pollution.