Investigation of furfural photolysis and photochemical aerosol formation kinetics
S.N. Dubtsov1, G.G. Dul’tseva1,2, M.E. Plokhotnichenko1,2, P.V. Koshlyakov1, T.V. Kobzeva1
1V.V. Voevodsky Institute of Chemical Kinetics and Combustion of the Siberian Branch of the RAS, 3 Institutskaya str., 3, 630090, Novosibirsk, Russia
2Novosibirsk State University, 2, Pirogova Str., Novosibirsk, 630090, Russia
Keywords: фурфураль, вторичные органические аэрозоли, фотохимические аэрозолеобразование, furfural, secondary organic aerosols, photochemical aerosol formation
Abstract
The kinetics of furfural photolysis in air and nitrogen at different water vapor concentrations is studied. The photolysis rate constants of furfural are shown to be the same in air and in nitrogen. An increase in the water vapor concentration from 0 to 18 Torr results in an increase in the photolysis rate by a factor of 1.5. It has been experimentally shown that the yield of aerosol products for С5Н4О2 photolysis in air is independent of [Н2O] and equals to 1.8 ± 0.2%, while the yield increases from 1 to 2% during the photolysis in nitrogen as [Н2O] increases from 0 to 18 Torr. HCO and furil radicals formed during С5Н4О2 photolysis have been detected and identified using the spin-trapping technique; this proves the radical mechanism of С5Н4О2 photolysis. The partial analysis of aerosol products is performed. It is shown that aerosol particles consist of a complex mixture of oxidative ring cleavage compounds and a small amount of products containing furan ring. Based on the experimental data, a qualitative scheme of the chemical processes describing the formation of gaseous and aerosol products during furfural photolysis is suggested.
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