INVESTIGADORES
BLANCO Maria Belen
artículos
Título:
Products and Mechanism of the Reactions of OH Radicals and Cl Atoms with Methyl methacrylate (CH2=C(CH3)C(O)OCH3) in the Presence of NOx
Autor/es:
M. B .BLANCO, I. BEJAN, I. BARNES, P. WIESEN AND M.A. TERUEL
Revista:
ENVIRONMENTAL SCIENCE & TECHNOLOGY
Editorial:
AMER CHEMICAL SOC
Referencias:
Lugar: Washington; Año: 2014 vol. 48 p. 1692 - 1699
ISSN:
0013-936X
Resumen:
The OH radical and Cl atom initiated photodegradation of methyl methacrylate has been investigated in a 1080 L quartz-glass environmental chamber at 298 2 K and atmospheric pressure of synthetic air using in situ FTIR spectroscopy to monitor the reactants and products. The major products observed in the OH reaction were methyl pyruvate (92 16) % together with the formaldehyde (87 12) % co-product from the C1-C2 bond cleavage channel of the intermediate 1,2-hydroxyalkoxy radical, formed by addition of OH to the terminal carbon of the double bond which is designated C1. For the Cl atom reaction the products identified were chloroacetone (41 6) % together with its co-product formaldehyde (35 5) % and methyl pyruvate (24 4) % together with its coproduct formylchloride (25 4) %. The results show that the fate of the intermediate 1,2-chloroalkoxy radical involves not only cleavage of the C1-C2 bond but also quite substantial cleavage of the C2-C3 bond. The present results are compared with previous studies, showing different branching ratios for the OH and Cl addition reactions in the presence of NOx. Atmospheric implications are discussed.