MECHANISM OF PROPYLENE DISPROPORTIONATION

Disproportionation of [1-14C] propene and [2-14C] propene has shown that the postulated four-center mechanism is correct over a cobalt-molybdate-alumina catalyst. At temperatures above 60 °C, the isomerization activity of the catalyst becomes a factor, so that at 160 °C, nearly one-half the [1-14C] propene has isomerized to [3-14C] propene prior to disproportionation. From experimental values of the rate constant for disproportionation and the degree of isomerization, rate constants for isomerization are calculated. The apparent energy of activation of the disproportionation reaction was found to be 7.7 kcal/mole and for the isomerization reaction 17.3 kcal/mole. © 1969.