Investigating Particle-Phase Chemistry between Products of Oxidation of α-Pinene and Phenol

SIJIA LIU, Celia Faiola, Sergey Nizkorodov, University of California, Irvine

     Abstract Number: 678
     Working Group: Aerosol Chemistry

Abstract
Understanding the chemical composition and aging of secondary organic aerosols (SOA) is crucial for predicting their impact on climate change. In this study, we investigate the particle-phase reactions between SOA compounds derived from the OH oxidation of α-pinene and phenol. The two types of SOA were generated separately in a batch mode smog chamber, collected on the same substrate, and subsequently allowed to mix and react under different humidity conditions. High-Performance Liquid Chromatography coupled with Electrospray Ionization High-Resolution Mass Spectrometry (UHPLC-ESI-HRMS) was used to elucidate compositional changes, with particular attention to the compounds only found in the mixed aerosol. We hypothesize that the chemical reactions between compounds that belong to distinct SOA types will lead to enhanced chemical complexity of the mixed SOA, including the formation of unique oligomeric compounds and other particle-phase reactions, potentially resulting in altered physicochemical properties such as increased viscosity and modified volatility.