Nitrous heterogeneous formation

Zhu, T., G. Yarwood, J. Chen, and H. Niki, Evidence for the Heterogeneous Formation of Nitrous Acid from Peroxynitric Acid in Environmental Chambers, Environ. Sci. TechnoL, 27, 982-983 (1993). 

Jefferson DA (2000) The surface activity of ultrafine particles. Phil Trans Roy Soc Lond A 358 2683-2692 Jose-Yacamai M (1998) The role of nanosized particles. A frontier in modem materials science, from nanoelectronics to environmental problems. Metall Mater Trans A 29 713-725 Kalberer M, Ammann M, Arens F, Gaggeler HW, Baltensperger U (1999) Heterogeneous formation of nitrous acid (HONO) on soot aerosol particles. J Geophys Res 104 13825-13832 Kamm S, Mohler O, Naumann KH, Saathoff H, Schurath U (1999) The heterogeneous reaction of ozone with soot aerosol. Atmos Environ 33 4651-4661... 

Related to the uptake and reaction of N02 into liquid water and at the interface is a so-called heterogeneous dark reaction of gaseous N02 with water vapor to form nitrous acid, HONO. Potential formation processes and reactions of HONO in the atmosphere have been reviewed by Lammel and Cape (1996). This is a fascinating reaction in that, despite decades of research, the mechanism is still not understood. It occurs on a variety of surfaces, including water and acid surfaces (e.g., Kleffmann et al., 1998) and, as discussed in this chapter, on soot as well. 

Sakamaki, F., S. Hatakeyama, and H. Akimoto, Formation of Nitrous Acid and Nitric Oxide in the Heterogeneous Dark Reaction of Nitrogen Dioxide and Water Vapor in a Smog Chamber, Int. J. Chem. Kinet., 15, 1013-1029 (1983). 

Of the numerous poisoning experiments that indicate heterogeneity of catalyst surfaces, reference may be made first to a study of selective poisoning made by Russell et al. (83,84). Russell and Ghering found that the rate of the hydrogenation of ethylene over reduced copper was not markedly affected by nitrous oxide but that the rate of ethane formation decreased rapidly as soon as the adsorbed nitrous oxide was decomposed. 

Jensen, A., Johnsson, J.E., and Dam-Johansen, K. (1993) Formation of Nitric Oxide and Nitrous Oxide from Heterogeneous Oxidation of Hydrogen Cyanide at Fluidized Bed Combustion Conditions. 12 Int. Conf. on Fluidized bed Combustion, ASME, New York, 447-454. 

By-Product Formation from other Substrates. The formation of nitrous acid and organic acid by-products during the heterogeneous nitration of other substrates was compared with the corresponding results during toluene mononitration. Besides toluene, the hydrocarbons studied were benzene, ethylbenzene, o-, m- and p-xylenes and mesitylene. In all cases, the normal mixed nitrating acid composition was used with organic/aqueous phase ratio of 2/3 and reaction temperature of 35 C. Fig.9 shows that the rate of formation of the mononitro products does not follow... 

The uptake and reaction of NO2 on soot is very important as a process to release nitrous acid (HONO) into the gas phase. The formation of HONO by the heterogeneous surface reaction and its enhancement by light irradiation has been found for the first time by Akimoto et al. (1987) relevant to the unknown radical source in a smog chamber (see column on p.278). The uptake of NO2 and photocatalytic reaction on soot has been interested in as a model reaction of such heterogeneous process to elucidate the characteristics of HONO formation in the atmosphere. 

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