Oxydation Entraînée des Hydrocarbures. I. Influence de la Stabilité des Radicaux Péroxydiques

The reactivity of cyclohexane in the catalyzed autoinitiated oxidation by cobalt naphtenate under an initial partial pressure of oxygene of 11 kg/cm 2 , in the presence of cumene was studied. The addition of about 5% in volume by cumene in the total volume of the mixture resulted in an increase in the rate of oxidation. In the oxidation of cyclohexane with cumene, the rate was doubled, while in the presence of cumene and a salt of cobalt, the rate of oxydation was 5 times as great. This increase in the rate of oxidation of cyclohexane by the presence of cumene corresponds to the increase in the rate at which this oxidation was initiated. This increase in the rate of initiation results from the increase in concentration of peroxydic radicals which corresponds to the disparition constant of cumyl peroxydic radicals which is about 600 times below the disparition constant of the cyclohexyl peroxydic radicals. The apparent energy of activation in the mixture is 28,5 kcal mol −1 in the temperature range of 130‐60°C.