Volatile organic compounds (VOCs) are emitted from anthropogenic and natural sources, mainly as gaseous, often non-polar compounds of high vapor pressure. Most of the VOCs at relatively low concentrations are harmless. The products formed during the oxidation of VOCs in the atmosphere can have a significant impact on air quality and can be harmful to human health. The major classes of VOCs include saturated hydrocarbons, unsaturated hydrocarbons, oxygenated compounds, etc. The double bonds in unsaturated compounds are very receptive to the addition of tropospheric oxidants, which initiate their photodegradation, leading to a short atmospheric lifetime and low global warming potential (GWP). However, understanding the fate of such molecules in the atmosphere is essential. The abundance of atmospheric oxidants like the OH radical, Cl atom, O3, and the NO3 radical varies significantly with location and time. Reactions involving OH radicals and Cl atoms gained special attention due to their faster reactivity and greater abundance. The kinetic and mechanistic investigations of photo-oxidation reactions of various unsaturated compounds like haloalkene1, unsaturated sulphide2, and cyclic unsaturated compounds3 with different atmospheric oxidants using both experiment and theory will be discussed in this seminar.
References:
1) Andersen, M.P.S., Volkova, A., Hass, S.A., Lengkong, J.W., Hovanessian, D., Solling, T.I., Wallington, T.J. and Nielsen, O.J. Physical Chemistry Chemical Physics, 2022, 24(12), 7356-7373.
2) Cardona, A.L., Gibilisco, R.G., Rivela, C.B., Blanco, M.B., Patroescu-Klotz, I., Illmann, N., Wiesen, P. and Teruel, M.A. Chemosphere, 2022, 288, 132546.
3) Giri, B.R., Mai, T.V.T., Assali, M., Nguyen, T.T.D., Nguyen, H.T., Szori, M., Huynh, L.K., Fittschen, C. and Farooq, A. Physical Chemistry Chemical Physics, 2022, 24(13), 7836-7847.