A Preliminary Study About Secondary Organic Aerosols Formation From Aldehydes In The Aqueous Phase Reaction

Atmospheric aerosols include primary aerosols and secondary aerosols. Secondary aerosols can be from new aerosol particles formed by photooxidation reaction and other chemical reaction of primary aerosols floating in the air. Secondary organic aerosols includes secondary inorganic aerosols and secondary organic aerosol (SOA, secondary organic aerosol).The study found that low volatile organic compounds and SOA can be produced by aqueous-phase reaction in clouds and aerosols.Isoprene is an important volatile organic compound in the atmosphere. It is oxidized by radical oxidant into small molecule compounds, such as glyoxal, glycolaldehyde and so on. The experiment simulated the glycolaldehyde reaction with nitrogen-containing compounds in cloud water (low concentration) and aerosol aqueous phase (high concentration) in the laboratory, and we studied the optical properties of the product.1. Reactions of ammonium sulfate with high and low concentrations glycolaldehyde.Glycolaldehyde is a widely present water-soluble organic compound with small molecular weight in the atmosphere, K*h,298>3×10M·atm-1. It is mainly from the degradation of isoprene and the oxidation of ethylene in the atmosphere. In order to simulate the reactions under different atmosphere conditions, we carried out the reaction of high and low concentrations glycolaldehyde with saturated ammonium sulfate. The properties of the two kinds of reaction products were preliminary analysed.2. Reactions of high and low concentrations glycolaldehyde with glycine.Amino acids are important components of atmospheric aerosols. Free amino acids have an important influence on the formation of sea salt aerosol. The reaction of amino acids affected the formation and deposition of atmospheric particles. So we carried out the reaction of two different concentrations glycolaldehyde with glycine,which is the simplest amino acid and has a high concentration in the air. We analysis the changes of productaccording to the light absorption properties.3. Reactions between glycolaldehyde with alanine.Because the R group of glycine is H, while the R group of the vast amino acids is carbon-containing group, we performed the reaction between different concentrations glycolaldehyde with another amino acid, alanine. The properties of the product were analyzed.