Methyl ethyl ketone photolysis

Figure 23. Comparison of residual spectra containing C=0 and 00N02 bands from the 03-TME-N02-air system. (A) 03-TME-14N02 system (B) 03-TME-15N02 system and (C) photolysis of a mixture containing Cl2, methyl-ethyl ketone, and N02 in air. Tentative identification of the product species is indicated.

Methyl ethyl ketone was detected in experiments above lOO C. Acetonyl acetone has not been identified in the products so far. Actually, not more than a small amount of this compound is expected to be formed, since (i) the acetyl radical is unstable at higher temperatures, and (ii) the rate of formation of acetonyl radical is slow at lower temperatures. The formation of biacetonyl was observed in the investigation of the reaction between CH3 and acetone . Brin-ton ° has succeeded in detecting biacetonyl also among the products of acetone photolysis in the temperature range 200-475°C. Most of the evidence on the formation of biacetonyl in the photolysis of acetone is, however, based on material bal-ance and hence is only of secondary importance. 

This class of organic compounds is exemplified by acetone and its higher homologues. As for the aldehydes, photolysis and reaction with the OH radical are the major atmospheric loss processes (Atkinson, 1989). The limited experimental data available indicate that, with the exception of acetone (see Figure 5.11), photolysis is probably of minor importance. Reaction with the OH radical is then the major tropospheric loss process. For example, for methyl ethyl ketone the OH radical can attack any of the three carbon atoms that contain hydrogen atoms ... 

Part 1. The photolysis of acetone -r iodine mixtures, Trans. Faraday Soc., 48, 812-823. Martin, G.R., and H.C. Sutton (1952b), Radioactive tracer studies of free radical mechanisms. Part 2. The photolysis of methyl ethyl ketone -r iodine mixtures, Trans. Faraday Soc., 48, 823-828. 

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