Photo-decomposition of Butyl Nitrite in the Atmosphere

Abstract

Photodecomposition of butyl nitrite in the air was carried out by irradiating light from 100 W high pressure mercury lamp with the maximum intensity at 365 nm. The decomposition didn't proceed in dark.
However the concentration of butyl nitrite decreased smoothly with time under irradiation, and 87% of butyl nitrite, of which initial concentration was 6430 ppm, was decomposed after 5 hours irradiation. The reaction followed a pseudo first-order rate law, and the effect of temperature was not observed between 30 and 50°C. The rate of decomposition increased with the decrease of the initial butyl nitrite concentration between 34 and 6430 ppm. No difference in the reaction was observed when oxygen and air was used as dilutant. However the reaction was suppressed by the presence of nitrogen or nitrogen monoxide and deviated from first-order rate law. The reaction products were butyraldehyde, 1-butanol, butyl nitrate, butyl butyrate and acidic products. On the basis of the experimental data and known atmospheric reaction, a mechanistic model was proposed.