Experimental data on SOA formation from mixtures of anthropogenic and biogenic organic compounds

Abstract

RESUMENLos aerosoles orgánicos secundarios (AOS) constituyen una fracción de las partículas atmosféricas. Este tipo de partículas se forman como consecuencia de la reacción de oxidación de ciertos gases orgánicos, lo que conduce a la formación de compuestos de baja volatilidad. Del mismo modo que para otros contaminantes atmosféricos, los modelos de calidad del aire permiten la simulación de partículas, una herramienta muy útil en tareas de gestión de la calidad del aire. Sin embargo, el uso adecuado de estos modelos debe basarse en la validación de su capacidad para reproducir las concentraciones observadas. Las estaciones de monitoreo de la calidad del aire registran información sobre una amplia variedad de contaminantes atmosféricos. Desafortunadamente, no se dispone habitualmente de medidas de AOS, ya que la instrumentación que se tiene en dichas redes de monitoreo no permite la diferenciación de las fuentes primarias y secundarias de los aerosoles orgánicos. Este documento presenta una serie de experimentos de fotooxidación realizados en las cámaras de simulación del Fotorreactor Europeo (CEAM, España) en diferentes condiciones experimentales con objeto de obtener datos sobre la formación de AOS. El uso de este tipo de cámaras permite aislar los procesos químicos y de formación de aerosoles, por lo que los datos presentados en este estudio tienen un considerable valor para propósitos de evaluación de modelos de formación de AOS, al igual que para el estudio del comportamiento de este tipo de partículas. ABSTRACTSecondary organic aerosols (SOA) constitute a significant fraction of the atmospheric particulate matter. Theses particles are formed as a consequence of the oxidation reaction of certain organic gases that leads to the formation of low-volatility compounds. As for other pollutants, air quality models allow the simulation of particle levels and thus models constitute a powerful tool in air quality management. Nevertheless, the Atmósfera 26(1), 59-73 (2013) 60 M. G. Vivanco et al. accepted use of models must be based on the validation of its capacity to reproduce observed concentrations. Air monitoring sites provide measured information of a large variety of ambient pollutants. Unfortunately, measurements on SOA are not normally available, as current monitoring networks do not include instrumentation to distinguish primary from secondary sources of organic carbonaceous aerosol. This paper presents a set of photooxidation experiments performed in the European Photorreactor (EUPHORE) smog chamber (CEAM, Spain) under different experimental conditions to investigate SOA formation. The use of chambers allows the isolation of atmospheric chemistry and aerosol formation processes. Thus, although these measurements were obtained at initial precursor concentrations higher than those in atmospheric conditions, they constitute a valuable set of information for SOA model evaluation purposes.

The influence of the addition of isoprene on the volatility of particles formed from the photo-oxidation of anthropogenic–biogenic mixtures

“…Previous studies have showed that when isoprene is mixed with another aVOC, the SOA particle yields can be reduced (Jaoui et al, 2008;Vivanco et al, 2013;Ahlberg et al, 2017). This may imply that either the potential molecular interactions resulted in higher-volatility products that remained in larger fractions in the gas phase, or that isoprene was scavenging the available OH, thus reducing the SOA particle mass formed from the oxidation of o-cresol.…”

Evaluation of some SOA formation schemes for the oxidation of anthropogenic gases against experiments in two outdoor chambers

“…Only four representative experiments are shown here in the interest of conciseness. The EUPHORE chamber and the associated analytical techniques are described by Vivanco et al (2011Vivanco et al ( , 2013. The selection of the EUPHORE experiments was based on a consistent estimation of particle concentrations from two different analytical instruments: a tapered element oscillating monitor (TEOM) and a scanning mobility particle siser (SMPS).…”

“…In this study, we present an intercomparison of different SOA mechanisms, with one-step, two-step and multi-step oxidation reactions for anthropogenic SOA precursors. A comparison of model results against two sets of experiments, performed in two outdoor chambers, UF (University of Florida, USA) and EUPHORE (Ceam, Valencia, Spain;Vivanco et al, 2013) Experiments in UF were performed for individual VOCs (toluene and 1, 3, 5-trimethylbenzene), whereas experiments in EUPHORE were performed with a mixture of four anthropogenic VOCs: toluene (TOL), 1, 3, 5-trimethylbenzene (TMB), o-xylene (OXYL) and octane (OCT).…”

Interaction between marine and terrestrial biogenic volatile organic compounds: Non-linear effect on secondary organic aerosol formation

“…The ambient atmosphere is a complex mixture of different organic gases, which can interact and mix to form SOA through the same emission source or in the atmospheric transport (Voliotis et al, 2022;Malik et al, 2018;Luo et al, 2015).The oxidation of organic gases with other VOCs produces more SOA with monoterpenes or sesquiterpenes in the mixed systems (Vivanco et al, 2011;Vivanco et al, 2013;Emanuelsson et al, 2013). Most of the monoterpenes and sesquiterpenes contain endocyclic carbon-carbon double bonds.…”