Proceedings of the Royal Society of London A Mathematical and Physical Sciences · 1956 · 32 citations · 3 references
Natural SciencesBiochemistryChemistryCatalysisInorganic ChemistryRedox BiochemistryCatalytic MechanismsCatalytic Reaction KineticsChemical Reaction KineticsMetal CatalysisOxidation ReactionsRedox ChemistryAcetaldehyde OxidationCobalt CatalysisCopper-catalyzed OxidationElectron TransferMetal-catalyzed OxidationMetals-catalyzed OxidationOxidation KineticsPeroxide Formation
Abstract The oxidation of acetaldehyde in glacial acetic acid catalyzed by manganese, copper and cobalt acetate has been studied at room temperature. Analyses of the products have been carried out, and it is shown that the reaction proceeds in two well-defined stages: (a) the oxidation of the aldehyde to peracetic acid; (b) the reaction of peracetic acid with acetaldehyde to give a second peroxide, X. The metal-salt-catalyzed decomposition of both peroxides has been determined. Kinetic measurements show that the oxidation with each of the metal acetates follows a similar course and conforms to the general kinetic relationship dO2/dt = k[acetaldehyde]3/2 [catalyst]1/2. These measurements, together with other observations, indicate that the initiating process is an electron-transfer reaction between the aldehyde and the higher valence state of the ion of the metal catalyst: M3+(M2+) + RCHO → M2+(M+) + RCO• + H+. This reaction leads to the establishment of the following chain process RCO• +O2 → RCOO•, RCOOO • + RCHO → RCOOOH + RCO•. The metal ion is maintained in the higher valence state by the reaction cycle RCOOOH + M2+(M+) → RCOO• +M3+(M2+) + OH-, RCOOOH +M3+(M2+) → RCOOO• + M2+(M+) + H+.
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