Identification and Kinetic Study of the Peroxymalonyl Radical in the Aerobic Oxidation of Malonic Acid by Cerium(Ⅳ)

摘要

The measured decay kinetics of MA~· as well as the MAOO~· (Figure 2a,b) are consistent with our numerical result, that oxygen is consumed within the first seconds of the reaction. During this period a distinct aerobic pathway is observed. When oxygen is depleted, the reaction switches to an anaerobic pathway. This means that the intermediates which are directly produced by oxygen (MAOO~· and MAOOH) are not able to maintain the reaction on the aerobic kinetic regime. Nevertheless, under initially aerobic conditions, it is highly probable that the oxygen-specific intermediates decay to products which are not formed under inert gas atmospheres. These products may account for long-term deviations between aerobi-cally and anaerobically run BZ reactions.